Health Disparities in Patients with Pulmonary Arterial Hypertension:A Blueprint for ActionAn Official American Thoracic Society StatementArunabh Talwar, Joe G. N. Garcia, Halley Tsai, Matthew Moreno, Tim Lahm, Roham T. Zamanian, Roberto Machado,Steven M. Kawut, Mona Selej, Stephen Mathai, Laura Hoyt D’Anna, Sonu Sahni, Erik J. Rodriquez, Richard Channick,Karen Fagan, Michael Gray, Jessica Armstrong, Josanna Rodriguez Lopez, and Vinicio de Jesus Perez; on behalf of thePulmonary Circulation Assembly
THIS OFFICIAL POLICY STATEMENT OF THE AMERICAN THORACIC SOCIETY WAS APPROVED OCTOBER 2017
Background: Health disparities have a major impact in thequality of life and clinical care received byminorities in theUnitedStates. Pulmonary arterial hypertension (PAH) is a rarecardiopulmonary disorder that affects children and adultsand that, if untreated, results in premature death. The impact ofhealth disparities in the diagnosis, treatment, and clinicaloutcome of patients with PAH has not been systematicallyinvestigated.
Objectives: The specific goals of this research statement were toconduct a critical review of the literature concerning healthdisparities in PAH, identify major research gaps and prioritizedirection for future research.
Methods: Literature searches from multiple reference databaseswere performed using medical subject headings and text words forpulmonary hypertension and health disparities. Members of thecommittee discussed the evidence and provided recommendationsfor future research.
Results: Few studies were found discussing the impact ofhealth disparities in PAH. Using recent research statementsfocused on health disparities, the group identified six majorstudy topics that would help address the contribution of healthdisparities to PAH. Representative studies in each topic werediscussed and specific recommendations were made by thegroup concerning the most urgent questions to address in futureresearch studies.
Conclusions: At present, there are few studies that addresshealth disparities in PAH. Given the potential adverse impactof health disparities, we recommend that research efforts beundertaken to address the topics discussed in the document.Awareness of health disparities will likely improve advocacyefforts, public health policy and the quality of care of vulnerablepopulations with PAH.
Keywords: pulmonary hypertension; health disparities; healthpolicy; genetics
ContentsOverviewIntroductionPurposeDefinition of Health Disparities andPAH
Methods
Evidence SynthesesPAH RegistriesGenetic Contributors to HealthDisparities in PAH
Medical Education: EducatingProviders, Raising Awareness,and Addressing Implicit Bias
Patient EducationHealth Policy
RecommendationsConclusions
The findings and conclusions in this statement are those of the authors and do not necessarily represent the views or the official position(s) of the NationalInstitutes of Health or any of the sponsoring organizations and agencies of the U.S. government.
An Executive Summary of this document is available at http://www.atsjournals.org/doi/suppl/10.1164/rccm.201709-1821ST
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Health disparities exert a disruptiveinfluence on the clinical outcomes andquality of care received by minorities inthe United States. Although initiativesaddressing health disparities have madesignificant advances, there are still majorgaps that will benefit from ongoing researchefforts. “Pulmonary hypertension” (PH)refers to a group of diseases characterizedby abnormally elevated pulmonarypressures caused by various chronicconditions (Table 1). Of the various formsof PH, pulmonary arterial hypertension(PAH) stands out as a rare disease thataffects predominantly women, with anestimated median survival of 2.8 yearswithout treatment (1). Available clinicalguidelines stress the importance of earlydiagnosis and initiation of therapy toensure optimal outcomes, reduce
morbidity, and maintain quality of life (2).Compared with the rest of the population,minorities with PAH may be at risk forworse outcomes due to difficulty accessinghealthcare, lack of or limited insurance,poor socioeconomic status, and distrust ofthe healthcare system, among other factors.Although few studies have addressed theseissues, our review of the available datasuggests that patients belonging to minoritygroups may have worse outcomescompared with other populations. Thecommittee reviewed the available literatureon health disparities to formulate thefollowing recommendations:
d There is accumulating evidence thatcertain minority groups have a geneticpredisposition for cardiovasculardiseases, but whether this is also the casefor minorities with PAH is unknown.Given the prognostic importance ofmutations, the group recommends that
the value of performing genetic screeningand providing gene counseling,particularly to patients with idiopathicand familial PAH, should be assessed byfuture research.
d Patient registries have historically lackedadequate representation of racial andethnic minorities, which limits ourcapacity to determine whether there aredifferences in clinical phenotypes andimplementation of therapies. Thecommittee recommends that effortsshould be made to ensure adequaterepresentation of minorities in clinicalregistries and to prepare questionnairesthat include questions relevant tominorities in accessible languages.
d Socioeconomic status (SES) is defined bya number of variables, includingeducation, occupation, marital status,health insurance coverage, and income.Lower SES has been linked to higherincidence of health disparities inminority populations with cardiovasculardiseases (3), making this one of our toppriorities to study. In PAH, SES has beenassociated with worse functional class atpresentation, as patients with lowerincome were likely to present atspecialized healthcare centers with moreadvanced PAH. The committeerecommends that SES should beincluded as a major variable in researchstudies, as it will help identify vulnerablepatients with risk factors that are uniqueto underrepresented minorities in theUnited States.
d Healthcare practitioners working in localand regional healthcare systems have theopportunity to identify minoritypopulations at risk and to create effectiveplans for interventions; however, theircapacity to do this is determined byidentification of and access toeducational and community-basedresources that will attract patients to seekhealthcare. The committee recommends(1) the use of educational resources forboth patients and practitioners and (2) amultidisciplinary approach that shouldincorporate social workers and medicalinterpreters to ensure trust and respectfor both parties.
d It is well established that PAH can resultfrom exposure to certain drugs andtoxins, infections, liver disorders,autoimmune disorders, and congenitalheart disease (2). In addition,environmental stressors such as
19. Pulmonary veno-occlusive disease and/or pulmonary capillary hemangiomatosis199. Persistent pulmonary hypertension of the newborn2. Pulmonary hypertension due to left heart disease2.1. Left ventricular systolic dysfunction2.2. Left ventricular diastolic dysfunction2.3. Valvular disease2.4. Congenital/acquired left heart inflow/outflow tract obstruction and congenital
cardiomyopathies3. Pulmonary hypertension due to lung diseases and/or hypoxia3.1. Chronic obstructive pulmonary disease3.2. Interstitial lung disease3.3. Other pulmonary diseases with mixed restrictive and obstructive pattern3.4. Sleep-disordered breathing3.5. Alveolar hypoventilation disorders3.6. Chronic exposure to high altitude3.7. Developmental lung diseases
pollution, living conditions, andnutrition are known to reduce quality oflife and the mental health of patients,and may be directly involved in PAHpathogenesis. The committeerecommends that studies be performedto identify specific stressors in relevantgeographical areas and associationsbetween stressors and medicalcompliance, outcomes, and quality oflife.
d At present, there is a major unmet needfor health policy initiatives to protectminorities, likely due to the lack ofstudies demonstrating the extent ofhealth disparities. Addressing healthdisparities is a challenge that requires thepooling of federal, community, andprofessional resources to facilitate thedevelopment of research projects,interventions, educational materials, andhealth policy designed to change clinicaloutcome among vulnerable minoritygroups. The committee recommendspartnering with professional andadvocacy organizations to increaseawareness and to increase collaborativeefforts to lobby for new laws to protectpatients with PAH.
Introduction
According to the 2010 U.S. Census,approximately 36% of the populationbelongs to a racial or ethnic minority group,and these numbers will likely increase overthe next decade. However, compared withthe rest of the U.S. population, manyminorities experience reduced quality of lifeas a result of health-related problems, incontrast to the rest of the U.S. population (2).To address this growing problem andprevent the potential catastrophicconsequences that this trend will have onthe U.S. health economy, government-sponsored efforts have been undertaken tounderstand the major sources of healthdisparities and to implement effectivepolicies.
Whereas most efforts have focused ontackling diseases with the highest rates ofmorbidity and mortality in the U.S.population (e.g., cardiovascular diseases,cancer, chronic obstructive pulmonarydisease), less attention has been given toPAH, for which current estimates indicate aprevalence of 15–50 cases per million (4, 5).Of major importance, survival is dependent
on early diagnosis and institution oftherapy. To date, little work has been doneto determine whether minorities affectedwith PAH are at higher risk of worseoutcomes compared with nonminoritiesand whether measures can be undertakento effectively improve access and quality ofcare for these patients. In a study involvinga Veterans Affairs cohort with 340 patientswith a documented right ventricularsystolic pressure greater than 60 mm Hg byechocardiography, only 17% carried adiagnosis of PAH in their medical record (6).This is of particular concern, as one specificdilemma in the treatment of PAH is that (1)even mild increases in pulmonary arterypressure are associated with increasedmortality (7) and (2) delays in diagnosis areassociated with worse outcomes (8). Areview of the U.S. National Center forHealth Statistics database for the years 1994to 1998 for death attributed to PAH by sex,age, and race over nine geographic regionsrevealed that African American womenwith PAH had the highest rates of mortalityacross all ages (9). Although this has notbeen confirmed, it raises the possibility thatthese issues could contribute to theobserved health disparities reported andsupport an urgent need to address howthese factors could have a direct effect onthe diagnosis and treatment of PAH inminority groups.
Purpose
Given the known effect of health disparitieson health-related quality of life for othercommon disorders, it is likely thatminorities suffering from PAH could benefitfrom a revised approach that incorporatesthe recommendations of the NIH Roadmapfor Medical Research, which calls forintegrating clinical, basic, and social scienceresearch to identify and treat factorsdirectly related to disparities in healthoutcomes (4). The American ThoracicSociety (ATS) is committed to medicaleducation of both healthcare professionalsand patients, with the goal of improvingglobal lung health and advocating forhealth policy that will directly benefit thewelfare of patients with lung disorders suchas PAH. We believe in initiating efforts toconfirm the existence of health disparitiesin PAH care, and propose that possibleresearch avenues and changes in healthpolicy should be a priority for the ATS and
other professional research societies, as thiscould have a profound and lasting impacton improving the quality of healthcareexperienced by minority populationsafflicted with this devastating disease.
Definition of HealthDisparities and PAH
Health disparities between populationgroups are defined as significant differencesin health that are closely linked to racialancestry, social, economic, and/orenvironmental differences. Healthdisparities adversely affect groups of peoplewho have experienced greater obstacles tohealth based on their racial or ethnic group;religion; socioeconomic status; sex; age;occupation; mental health; cognitive,sensory, or physical disability; sexualorientation or sex identity; geographiclocation; or other characteristics historicallylinked to discrimination or exclusion (10).
PH is defined as an increase in meanpulmonary arterial pressure equal to orexceeding 25 mm Hg at rest as measured byright heart catheterization. PH is classifiedinto five groups (see Table 1) based on causeand hemodynamics criteria. PAH(i.e., World Health Organization [WHO]group 1 PH) is further defined by (1) meanpulmonary arterial pressure equal to orgreater than 25 mm Hg, (2) a pulmonaryartery wedge pressure not exceeding 15 mmHg, and (3) pulmonary vascular resistanceof at least 3 Wood units in the absence ofother causes of PH (WHO groups 2–5) (2).
Methods
Fifteen experts in PAH clinical care andresearch (basic, translational, and clinical),together with public health and policyresearchers with an interest in healthdisparities, were selected to discuss currentstrategies to diagnose and treat patients withPAH in the context of a research frameworkapplied to study health disparities in theUnited States. To meet our goals, thefollowing topics were selected for review:
1. Role of national PAH registries incollecting clinical data for research inhealth disparities
2. Role of genetics of PAH pertinent toclinical phenotypes in underrepresentedminorities
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3. Role of environmental stressors ininfluencing patient attitudes andresponse to therapy
4. Role of socioeconomic status inidentifying at-risk patient populationswith PAH
5. Role of medical education inestablishing the basis of a mutuallyrespectful and productive relationshipbetween minority patients andhealthcare practitioners
6. Partnerships between federaldepartments and medical societies todevelop health policy and advocacy forminorities with PAH
Before the face-to-face meeting at the2016 ATS International Conference, thechair and vice-chair performed a search ofthe medical literature to collect availableliterature on health disparities research inPAH and other relevant medical disorders,and distributed it to the rest of the panel. InMarch 2016, the committee held the firstteleconference to go over the topics to beincluded in the research statement. Sixteams were formed, and the members wereassigned to undertake a literature review andprovide a preliminary summary to the groupin time for the second teleconference.Literature searches were performed inMedline, and results were limited to humanstudies published in English for allpublication years. The groupmet face to faceonMay 14, 2016 in San Francisco at the ATSInternational Conference, where each of thetopics was presented as a PowerPointpresentation that summarized (1)background, (2) supporting literature,(3) findings, and (4) preliminaryrecommendations to be included in theresearch statement. After the meeting, thegroup worked on the first draft of theresearch statement and conducted severalteleconferences to discuss necessarychanges in the content of the document.Potential conflicts of interest weremanaged in accordance with thepolicies and procedures of the AmericanThoracic Society.
Evidence Syntheses
PAH RegistriesRegistries and observational cohort studieshave significantly contributed to ourunderstanding of PAH. The NationalInstitutes of Health (NIH; Bethesda, MD)-
supported Patient Registry for theCharacterization of Primary PulmonaryHypertension elucidated the clinicalcharacteristics and natural history of 187U.S. patients with primary pulmonaryhypertension (now called idiopathic PAH)enrolled from 1981 to 1985 (1, 11).Consequently, a number of cohort studiesand registries have studied predictors ofoutcome and survival of PAH in themodern era. These studies have focused onindividual centers, consortia of centers, andentire countries (12–20). Not surprisingly,variations in patient age, sex, race/ethnicity,country of origin, medical treatments, andSES have been linked with types of PAH,response to therapy, and outcomes.Although some of these findings may beinherently explained by genetic andbiological differences between patients,some are likely attributable toenvironmental factors, income and SES,prenatal and environmental exposures,cultural differences, diet, and availabilityand affordability of medical treatments.Data from registries that study such factorscould direct interventions that would befurther tested in randomized clinical trialsto improve outcomes in high-risk patients.
Small, single-center cohort studies havesuggested that race and SES may beassociated with survival in PAH. A study ofincident patients with PAH in the UnitedStates found that patients who were black orAsian had a higher risk of deathindependent of other covariates, such ascardiac index (16). Wu and colleaguesstudied a cohort of 262 incident Chinesepatients with idiopathic PAH, whichshowed that lower SES (as measured byeducational level, annual householdincome, occupation, and medicalreimbursement rate) was associated with ahigher risk of clinical worsening andmortality (3). These findings wereindependent of hemodynamics and otherdemographics and were not explained bydifferences in medical treatments. Severalcohort studies have shown that men withPAH have a higher risk of death thanwomen (21, 22), explained in one study bydifferences in improvement in rightventricular (RV) function with PAHtherapies (23). REVEAL (Registry toEvaluate Early and Long-Term PulmonaryArterial Hypertension DiseaseManagement) was a United States–based,multicenter (55 centers), 5-yearobservational disease registry. REVEAL
enrolled 3,515 consecutive consentinggroup 1 patients (2,555 previouslydiagnosed and 960 newly diagnosed[i.e., within 90 d of enrollment]) betweenMarch 2006 and December 2009 (12).Surprisingly, Brown and colleagues foundthat sex, race/ethnicity, and geographicregion were not associated with time todisease recognition in PAH (24). Frantzand colleagues also identified regionalheterogeneity in prostanoid use in thiscohort; however, this was not explained byrace or geography (25). On the other hand,in unpublished work from REVEAL,patients were stratified into ZIP code–basedmedian income, using 2000 U.S. Censusdata (,$40,000, >$40,000 and ,$60,000,>$60,000 and ,$80,000, and>$80,000/yr). Black and Hispanic raceswere reported at a higher frequency in thelower two income categories (15.98 and10.20%, respectively) compared with thetwo higher income categories (6.49 and4.67%, respectively). Clinically, the highestpercentage of functional classes 3 and 4 atbaseline was noted in the ,$40,000 incomegroup compared with the other incomegroups. Lower income groups had longertimes to disease recognition: mean (6SD)of 19.2 (645.2), 20.1 (641.5), 18.5 (639.8),and 17.0 (642.1) months for the incomegroups ,$40,000, >$40,000 and ,$60,000,>$60,000 and ,$80,000, and >$80,000/yr,respectively.
PAHQuERI (Pulmonary ArterialHypertension-Quality EnhancementResearch Initiative) is a UnitedStates–based, multicenter (60 centers),3-year observational disease registry of791 patients with PAH. In PAHQuERI,employment status (employed vs.unemployed or receiving disability) wasidentified as a predictor of 3-year mortality(P, 0.0001) (26). Further work examinedthe association between race, marital, andemployment status and known prognosticPAH parameters (baseline functional class,BNP levels, and 6-min walking distance)and death. Of note, race and ethnicity werenot associated with these outcomes(unpublished data).
MESA (Multi-Ethnic Study ofAtherosclerosis) is an NIH-fundedprospective cohort study of community-based participants without clinicalcardiovascular disease at baseline,oversampled for racial/ethnic minorities (27).A subset of participants had availablemagnetic resonance imaging assessment of
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RV size and function. There were significantdifferences between black, white, Asian, andHispanic participants in RV size andfunction, independent of other confounders(28). Age- and sex-related differences werealso seen, with older participants havingsmaller RV size and men having significantlylower RV ejection fraction than women (29).Genetic variants in genes in sex hormonepathways impacted on RV morphology andfunction in a sex- and race-specific manner(30), suggesting that possible disparities inoutcome between men and women anddifferent races and ethnicities could beattributable to differences in baseline RVmorphology and/or function. Traffic-relatedair pollution and particulate matter alsoimpacted on the RV (31, 32); suchenvironmental exposures may differ acrosspatient populations with pulmonary vasculardisease, and could impact outcomes,especially in low-SES populations.
Several active registries may be useful forfuture studies of disparities in the care andoutcomes of patients with PAH. ThePulmonary Hypertension Association (PHA)Registry is assessing adherence to guidelines,treatment patterns, quality of life, andoutcomes of patients with PAH and chronicthromboembolic pulmonary hypertension,who begin their care at pulmonaryhypertension care centers, accredited bythe PHA for their track record in thecare of patient with PAH. Self-reportedrace/ethnicity, primary language spoken athome, and various individual indicators ofSES (including residence address) are collectedin this registry. Over time, this informationwill be used to measure adherence todiagnostic and treatment guidelines, assesspatient outcomes, improve the quality of care,and facilitate research studies in PAH andchronic thromboembolic pulmonaryhypertension. Another ongoing registry isPAHQuERI Ex (PAHQuERI Extension), aUnited States–based, multicenter (71 centers),3-year observational disease registry of 799consecutive consenting group 1 patients withPAH focused on treatment practices andadherence to PAH treatment guidelines. Thedata collected by these registries will providemuch needed insight and help identifyvulnerable populations affected by healthdisparities.
Several features of current and futureregistries will be critical for studyingdisparities in generalizable ways. The useof common data elements ensuresstandardization of data (and collection
methodologies), facilitating the comparisonof results across studies and the aggregationof information into meta-analyses. Thecollection and coding of self-determined race,ethnicity, and other factors, using consistentapproaches, is necessary to ensure that dataare defined in the same way, use the samestandards, and employ the same vocabulary.This allows not only for generalizability topopulations but also for sharing andexchange of information across registries.
As heart and lung structure andfunction may be impacted by events rangingfrom the prenatal period to old age,registries should span the life cycle (33, 34).The inclusion of children and their parentsshould be the norm in registries. Studiesshould target individuals with preclinicaldisease or at increased risk (e.g., systemicsclerosis) for PAH to identify potentialsecondary prevention approaches.Validated and standardized translations ofdata collection instruments and quality oflife questionnaires for PAH into Spanishand other languages will be necessary toinclude minority populations of interest.Finally, data sharing should be theexpectation for all new studies to enablecollaborations across registries.
In conclusion, data supporting healthdisparities from PAH cohort studies andregistries are sparse. The lack of consistentassociations between demographic and SEScharacteristics and outcomes in PAH maybe due to the paucity of studies focused ondisparities and the limitations of the existingdata. Although PAH registries are apotentially rich source of insights into healthdisparities, the conclusions drawn arelimited by the granularity of the data on thevariables of interest and their interaction.For example, race and income, althoughfrequently used as SES indicators, areinextricable from other socioeconomic-related domains, such as education,employment, environmental exposures,diet, physical activity, and stress. Informedby learning from SES research in otherdisease areas, new PAH registries shouldexamine these factors as a conglomerate ofsocioeconomic components (captured in ascore or composite), rather than asindividual, isolated parametrics.
Genetic Contributors to HealthDisparities in PAHThere has been an immense expansionof knowledge that has focused on thecellular and molecular basis of PAH
pathophysiology. Among potential riskfactors for the development of PAH, geneticcontributors have been well documented bytraditional genetic approaches. In addition,transcriptomic, epigenomic, metabolomic,and proteomic techniques are increasinglybeing deployed in the investigation of PAHpathobiology. These studies have clearlyestablished the contribution of specificcandidate genes to hereditary (and in somecases idiopathic) PAH such as bonemorphogenetic protein receptor type II(BMRPR2) (35–38), activin A receptor typeII-like 1 (ACVRL1/ALK1), endoglin (ENG)(39), caveolin-1 (CAV1) (40), potassiumchannel two pore domain subfamily Kmember 3 (KCNK3) (41), and eukaryotictranslation initiation factor 2a kinase 4(EIF2AK4) (42). Common variants of genesencoding prostacyclin and endothelin-1pathways (43, 44), calcium signaling (45),sex hormone metabolism (46), and theendostatin gene (47) have been linked toPAH susceptibility. A genome-wideassociation study in patients with familialor idiopathic PAH failed to identify single-nucleotide polymorphisms that reachedgenome-wide association significance (48).However, in two separate cohorts, anassociation between PAH (with no knownBMPR2 mutations) and two polymorphismsnear the gene that encodes cerebellin-2(CBLN2) was reported (48). Exomesequencing has also identified variantsassociated with PAH susceptibility (47) andvasoreactivity (49, 50). Several publishedstudies have used genome-wide RNAexpression profiling platforms to assesspathways potentially associated with PAHand vasoreactivity (50–52). Similarly,studies suggest that abnormalities in theexpression of microRNAs and activity areassociated with PAH (53).
In spite of these significant advances,little is known regarding the role of geneticcontributors to PAH susceptibility inminority populations, as all of the above-referenced studies used cohorts of Europeandescent. These observations are consistentwith a position report detailing a major lackof diversity in biomedical research studysubjects and the significant barrier that thelack of diversity imposes to the fullunderstanding of factors that lead to diseaseor health (54). There are, however,examples of studies evaluating the roleof race and ethnicity in the geneticsusceptibility to other lung disorders. Forexample, racially specific variants have been
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associated with acute respiratory distresssyndrome susceptibility in AfricanAmerican patients (55). Variants in humanMYLK (encoding myosin light chain kinase,a key regulator of cytoskeletal dynamicsand vascular permeability) were associatedwith increased susceptibility to acuterespiratory distress syndrome and sepsis insubjects of African descent, with thesesingle-nucleotide polymorphisms beingextremely rare in non-African populations(56, 57). Racial- or ethnic-specific variantsare also associated with asthma and chronicobstructive pulmonary disease susceptibilityand with asthma severity both in AfricanAmericans (58–63) and Latinos (62,64–66). Candidate gene and genome-wideassociation studies have not only confirmedassociations between “European descent”risk variants in African Americans andLatinos but have also uncovered novelvariants specific to racial and ethnicpopulations (58, 59, 67, 68), with rare andlow-frequency variants linked to asthmasusceptibility in African Americans andLatinos (69). Another importantconsideration is the overall contribution ofancestry to disease risk stratification andsusceptibility. For example, Africanancestry increases asthma susceptibility(61, 70), whereas Native American ancestryis associated with a lower risk of asthmaand a greater bronchodilator response tob-agonist treatment (71–73). This isparticularly evident in Latinos who havedescended from Native American,European, and African populations.Asthma prevalence, morbidity, andmortality are highest in Puerto Ricans (withthe highest proportion of African descent),intermediate in Dominicans and Cubans,and lowest in Mexicans and CentralAmericans (with the lowest proportion ofAfrican descent DNA) (74).
The integration of molecular, genomic,and clinical medicine in the postgenome eraprovides the promise of novel informationon genetic variation and pathophysiologiccascades in PAH. The current challenge is torapidly translate these discoveries into viablebiomarkers that identify susceptiblepopulations and facilitate the developmentof targeted therapies for patients with PAH.This challenge will not be fully met in anenvironment lacking studies evaluating therole of genetics, race, ethnicity, andmagnitude of PAH susceptibility/severity inminorities. The technology to meet thischallenge is now readily available; however,
given the limited nature of PAH, futurestudies will require a global approachinvolvingmultiple investigators andmultiple,highly diverse patient cohorts. Efforts such asthe National Biological Sample and DataRepository for Pulmonary ArterialHypertension (also known as the PAHBiobank), the Pulmonary Vascular DiseasePhenomics Program (PVDOMICS) in theUnited States, and BRIDGE-PAH in theUnited Kingdom represent platforms fromwhich future studies could be launched.
Socioeconomic StatusSES is defined as an individual’s social andeconomic standing, and is a measure of anindividual or family’s social or economicposition or rank in a social group (75). It isgenerally a composite of several measuresincluding income, education, occupation(including employment status), location ofresidence, and housing (including homeamenities), and may also includeparticipation in social organizations(75–77). Of all the measured demographicsin healthcare today, SES may be the leastreported but the most influential in apatient’s access to healthcare and clinicaloutcomes (Figure 1) (78). The UnitedStates, which uses a combination of privateand government-sponsored health
insurance, is in contrast to other countries,which provide nationalized health coverageor none at all. However, despite efforts bymany national governments to provide allmembers of society with equal access tohealthcare, SES still has a profound effecton life expectancy and is still independentlya risk factor for death, as higher income isassociated with greater longevity (79).
Traditional SES measures includeoccupation, education, and income(Table 2) (80). Each of these measurescaptures a distinct aspect of SES, and maybe correlated with other measures.Examples include occupation, employmentstatus, education, and direct measures offamily income (80). Obtaining traditionalmeasures of SES may not always be feasiblebecause of missed recordings, personalnature of questions, discrepancies inreporting, and instructional review boardconstraints. In addition, it may be difficultto assess income because of inaccuratepatient reporting, employment statuschanges, or unforeseen circumstances. Also,as SES in epidemiological studies is oftenretrospective, relying on traditionalmeasures of SES may lead to a bevy ofmissing data (80). Braveman and colleaguesnoted that there is an inherent problem inmeasuring SES, which could affect research
Health Insurance Status
Poor Healthcare Access
Effects on Treatment andClinical Outcomes ofChronic Respiratory
Disease
Inadequate availabilityof advanced diagnostic
modalities
Inability to timelydiagnose advanced
lung disease
Delay in referral toadvanced lung disease
centers (specialistcenters)
Socioeconomic Status (SES)
Income
Occupation Education
Healthcare Disparities
Low SES
Figure 1. Proposed relationship between socioeconomic status and healthcare access in the settingof pulmonary arterial hypertension. Adapted by permission from Reference 131.
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American Thoracic Society Documents e37
findings and conclusions with implicationsfor practice and policy (81). For suchreasons, surrogates for the measurement ofSES, such as contextual measurements, havebeen formulated. Contextual measures ofSES focus on ecological and geographicvariables and may involve a combination ofboth and are more feasible to obtain.Contextual approaches to SES examine thesocial and economic conditions that affectall individuals who share a particular socialenvironment. Examples of contextualmeasures of SES may be at theneighborhood level and include ZIP codes,census tracts, census block groups, orcensus blocks (80).
PAH and SES. Despite thedevelopment of numerous therapies overthe past 20 years, the delay to diagnosis hasnot decreased over the past three decades(1, 82). Although its role has not been asexhaustively explored in PAH, SES isassociated with more severe disease atpresentation (83). A study by Talwar andcolleagues (83) showed that as medianincome decreased, the WHO functionalclass at presentation of both patients withPH and patients with PAH increased. Thisassociation between median income groupsand WHO functional class at initialevaluation was statistically significant. Onepossible reason for the delayed diagnosisand more severe disease at presentation forlower SES individuals may be reducedaccess to advanced diagnostic proceduressuch as right heart catheterization (84).
SES not only plays a role in thediagnosis and treatment of the disease, italso has a profound effect on the clinicaloutcome of these patients. In a study by Wuand colleagues, it was found that lower SESwas strongly associated with a higher risk of
death in PAH. Patients who were consideredto have lower SES had a higher unadjustedmortality rate, with 3-year survival estimatesof 50.1, 70.8, and 86.0% in increasing tertilesof SES (3). After adjustment for age, sex,clinical features (WHO group),hemodynamics, and type of PAH therapy,the hazard ratios for death were 2.98 (95%confidence interval, 1.51–5.89) in the lowesttertile of SES and 1.80 (95% confidenceinterval, 0.89–3.63) in the middle tertile ofSES compared with the upper tertile (P fortrend, 0.006). What this study highlights isthat despite disease severity, hemodynamics,or treatment type, patients with lower SEShave a higher risk of all-cause mortality inPAH.
SES: measurement and unequaltreatment subsections. Determining howkey determinants of health are measuredand presented as medical and insurance datahas been of interest to the National ResearchCouncil of the National Academies. In theirreport entitled Eliminating HealthDisparities: Measurement and Data Needs,the National Research Council highlightedthe importance of these data inunderstanding health disparities, generallyaccepted measures of these determinants,and the collection of these data by theDepartment of Health and Human Services(HHS), state-based agencies, and private-sector organizations (85). The HHS collectskey determinant data in medical dataprimarily through surveys or administrativedata systems. Surveys such as the NationalHealth Interview Survey also serve as asampling frame for the MedicalExpenditure Panel Survey and the NationalSurvey of Family Growth, which allow fordata linkage. Each of these surveys collectsthe following categories of race: White,
Black, Asian, American Indian or AlaskaNative, or Native Hawaiian or Other PacificIslander. Respondents may also indicatemultiple categories of race or Hispanicethnicity. Some surveys, such as theNational Health Interview Survey and theNational Immunization Survey, allowrespondents to choose an Asian or Latinonationality. With respect to SES, all three ofthe aforementioned surveys collect data onemployment status, occupation, sourcesand amounts of income, and educationlevels. The Medical Expenditure PanelSurvey also collects data on wealth byasking about the estimated value of assetsand debts. Collection of language use andacculturation data in these surveys intypically limited to items such as place ofbirth, country of origin, and languagespoken at home or language of interview.
Provider-based surveys are conductedamong hospitals, physicians’ offices, andclinics. Data records are prepared inconjunction with the service provided. HHSsurveys include the National AmbulatoryMedical Care Survey, National HospitalDischarge Survey, Healthcare Cost andUtilization Project, and the National Homeand Hospice Care Survey. In these surveys,race and ethnicity data may be collected bystaff from the record or sometimes byasking the patient about their race andethnicity. Missing data are common inprovider-based surveys as well. Theprevalence of missing race and ethnicitydata can range between 20–40% and30–87%, respectively, depending on thesurvey.
The collection of SES data in provider-based surveys is limited at best. The reasonfor collecting such data is to ensure paymentfor the service provided. This may includeinformation that pertains to the individualor the government program in which theindividual is enrolled. In addition, provider-based surveys rarely collect data onacculturation and language use. The onlysurvey that does, the National Survey ofSubstance Abuse Treatment Services,collects data on the language offered intreatment services. For rare diseases, such asPAH, one of the challenges of a nationalsurvey is sample size. Typically, nationalsurveys do not employ a case–control studydesign, therefore making it difficult toassess PAH. A cost-effective solution to thiswould be to include a supplemental surveyof individuals with PAH in nationalsurveys. Medicare data has provided
Table 2. Traditional Measures of Socioeconomic Status
d Occupation∘ Employment status (e.g., employed/unemployed/retired)∘ Specific occupational group∘ Aggregate occupation groups∘ Blue-collar/white-collar workers
d Education∘ Years of education (aggregate)∘ Highest educational level completed (i.e., high school, college, etc.)∘ Credentials earned (e.g., high-school diploma, bachelor’s degree, graduate degrees)
d Income∘ Individual annual income∘ Annual household income (aggregate)∘ Family income
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researchers an opportunity to study healthdisparities for decades. The primary sourceof racial/ethnic data linked to Medicarerecords is the Medicare EnrollmentDatabase (EDB). Race/ethnicity in the EDBis obtained from the Social SecurityAdministration (SSA). However,racial/ethnic data are not available for allMedicare enrollees, and racial/ethniccategories have changed over time. Forregistrants after 1989, no racial/ethnic datawere collected because race/ethnicity onbirth certificates was deemed unnecessaryby the SSA. However, if an individual hasapplied for a new social security number orchanged his or her name, using an SS-5form, then racial/ethnic data would havebeen collected. Until 1980, categories ofrace/ethnicity included White, Black,Other, and Unknown for those notreported. Since 1980, race/ethnicity hasbeen categorized into White, Non-Hispanic; Black, Non-Hispanic; Hispanic;North American Indian or Alaska Native;and Asian, Asian American, or PacificIslander. However, data by these categorieswere collected only for individuals whofilled out an SS-5 form. In 1994,racial/ethnic data from SS-5 forms wereintegrated into records to correct and fill inmissing information. This integrationreclassified 30% of individuals to a newrace/ethnicity. Updates were repeated in1997, 2000, 2001, and further plannedannually. In 1997, a postcard survey wasmailed to enrollees with Latino surnamesand with “Other” or “Missing” race codes.Forty-three percent of postcard recipientsresponded to the survey. In addition, racewas also obtained from beneficiary-levelinformation from 32 states for Medicaidenrollees as well as from the End-StageRenal Disease Medical Evidence Report.However, high levels of misclassification ofrace/ethnicity have been reported whencompared with the Medicare CurrentBeneficiary Survey, a household survey ofHHS. Interestingly, the lowest levels ofmisclassification occurred among white orblack individuals.
Data on SES are not collected byMedicare, but socioeconomic status can beestimated by merging SSA earnings datawith EDB data. However, there are certainproblems with this estimation. First, thisapplies only to jobs that are covered bySocial Security. Therefore, data may not beobtained for some immigrant populationswith undocumented earnings. Second, it is
not a reliable measure of lifetime income forindividuals who did not work their entirelifetime in the United States. Third, it doesnot capture wealth, whichmay be significantcompared with earnings. This is particularlyrelevant for spouses who worked very littlebut who have substantial wealth from theirworking spouses, and/or for divorcedspouses who worked little while married.Last, for individuals who meet themaximum earnings for Social Security,actual earnings are not reported. Neitheracculturation nor language data arecollected by these data sources. Otherresources such as the Medicare CurrentBeneficiary Survey and the MedicareSatisfaction Survey of the ConsumerAssessment of Health Plans Survey(CAHPS-MSS) ask about race/ethnicity andsocioeconomic status. CAHPS-MSS alsocollects data on acculturation and languageuse. Both sources rely on administrativedata, which reduces the problem ofmisclassification dramatically. Other publicinsurance data sources, such as the IndianHealth Service, collect demographic data butdo not assess socioeconomic status orlanguage use. State-based collection ofmedical and insurance data includes theVital Statistics Birth and Death Records,Hospital Discharge Abstracts, and Medicaidand the State Children’s Health InsuranceProgram. In the Vital Statistics Birth andDeath Records, the reporting ofrace/ethnicity, education level, and countryof origin or parents are standardized.However, death certificates do not containcountry of origin or language use.Race/ethnicity categories for Asians areimproved beyond traditional categoriesmentioned above to include separate Asiancategories, separate Pacific Islandercategories, and a “Specify” line for tribe.Hispanic ethnicity was recommended to beadded as additional data. With respect tomisclassification, white individuals aremisclassified the least and nonwhiteindividuals were misclassified significantlymore often. The worst rates ofmisclassification were among AmericanIndian and Alaska Native populations,Asians and Pacific Islanders, which wereoften misclassified as White. HospitalDischarge Abstracts are mandated by 37states, 27 of which include nonstandardizedmethods of collecting race/ethnicity. Datain the Healthcare Cost and UtilizationProject, the national-level data set forhospital discharge data, vary by state level.
This often leaves race/ethnicity dataincomplete and inconsistently formatted.
With the limited data that we haveregarding PAH, it is imperative that furtherresearch be conducted to determine theeffect of SES on these patient populations.There seems to be a profound effect of SESon disease severity and clinical outcomes inPAH. It is plausible that lower SES patientsalso suffer from lack of healthcaresupportive services. In general, it is believedthat these patients will benefit from supportgroup prescription (86), but otherinterventions may be required to addressthe challenges posed by PAH.
Environmental Stressors andPulmonary Vascular DiseaseThere is a paucity of data examining theimpact of the physical and socialenvironment on pulmonary vasculardisease. Exploring the contributions ofenvironmental stressors has the potential tobe a useful endeavor for improving ourunderstanding of the mechanismsunderlying this disease, and for highlightingsome strategies to prevent or slow theprogression of disease.
Air pollution. Outdoor and, to a lesserextent, indoor air pollution has been shownto increase risk of morbidity and mortalityassociated with cardiopulmonary diseasessuch as myocardial infarction, stroke,arrhythmia, heart failure, chronicobstructive pulmonary disease, and asthma(87). This relationship may be even morepronounced in developing nations that lackenvironmental protection plans; findingsfrom the Health Effects Institute (Boston,MA) demonstrate that ambient particulatematter and household air pollution are nowthe fourth and fifth leading causes of deathin East Asia (88). However, much less isknown about the relationship betweenambient pollution and pulmonary vasculardisease (89, 90). There is a strong rationalefor a link between specific types of airpollution, such as particulate matter, andvascular disease (91). Prior epidemiologicand basic studies have demonstratedhypercoagulability in response toparticulate matter exposure, evidenced byincreased plasma levels of factor VIII, vonWillebrand factor, and fibrinogen (92, 93).Air pollution may also influence RVstructure and function, independent fromunderlying cardiovascular disease. Asshown by Leary and colleagues, usingcardiac magnetic resonance imaging from a
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large cohort of patients in MESA Air(Multi-Ethnic Study of Atherosclerosis andAir Pollution), exposure to nitrogen dioxidewas associated with increased RV mass andlarger RV end-diastolic volume (32).However, whether exposure to air pollutionin general or to specific componentsinfluences the risk of development of PAHor is a disease modifier remains to bedemonstrated.
Diet/nutrition. A wealth of dataindicates that types of diet are associatedwith either protective or damaging effects oncardiovascular health. The mechanism ofthe effect of diet on cardiovascular functionis not completely understood, but is thoughtto be mediated through oxidative stress andresultant endothelial dysfunction.Comparably fewer data exist regarding theassociation between diet and pulmonaryvascular disease and, unfortunately, thesedata are conflicting. Nutrient deficiencieshave been associated with PAH and areimplicated in the pathogenesis of pulmonaryvascular remodeling. Specifically, irondeficiency has been implicated in thepathogenesis of pulmonary vascularremodeling (94, 95). Clinical associationsbetween iron deficiency, even in patientswithout overt anemia, and severity of PAHhave been reported (96, 97). A clinical trialof supplemental iron in idiopathic PAH iscurrently ongoing (98).
Medical Education: EducatingProviders, Raising Awareness, andAddressing Implicit BiasRacial and ethnic minority patients tend toreceive a lower quality of healthcare thanwhite patients (99). The sources of thesedisparities are complex and multifactorial,and involve the patients, health systems,and healthcare providers (99). Whensociocultural differences between patientand provider are not appreciated in themedical encounter, the result is patientdissatisfaction, poor adherence, poorerhealth outcomes, and racial/ethnicdisparities in care (100–105). There is apaucity of data specifically looking at healthdisparities in minority populations ofpatients with PAH, but one can assume thenegative effects are similar to those of otherchronic diseases such as cardiovasculardisease and cancer.
Physician bias toward certain racial orethnic groups is a real problem and has beendescribed. In a study by Schulman andcolleagues, physicians who were asked to
recommend treatment for hypotheticalpatients of varying races and sexes werefound to recommend cardiac catheterizationsignificantly less often for black females thanfor any other group of patients with thesame symptoms, after controlling for thephysician’s assessment of probability ofcoronary arterial disease, age of patient,level of coronary risk, type of chest pain,and exercise test results (106). In anotherstudy examining the association betweenpediatricians’ attitudes toward race andprescribing medications, there was thepresence of a pro-white bias, as participantsimplicitly associated African Americanpatients with nonadherence despite absentexplicit biases. In addition, postsurgicalnarcotic medications were prescribed lessfrequently for African American childrenwith pain, again associated with a pro-whitebias (107). These implicit (or “unconscious”)biases of physicians are pervasivethroughout society, and therefore notunexpected among physicians.
There are many potential reasons whyhealthcare providers in settings with largenumber of minority patients may not beaware of PAH. Providers may miss thediagnosis because of the presence of morecommon diseases such as obesity, asthma,diabetes, heart failure (both with reduced orpreserved ejection fraction), and drug ortobacco use (6). There are also challengesassociated with obtaining accurate historiesbecause of language and/or culturalbarriers. Last, providers may have moredifficulty getting studies (echo, right heartcatheterization) approved and/or scheduled(6). Furthermore, minority patients withPAH are frequently seen in emergencydepartments where they use healthcareresources, but are not referred for specialistcare (108, 109). Solution strategies includedeveloping educational strategies aimed atspecifically targeting healthcare providers inthese settings, and emphasizing the role ofearly diagnosis and early referral. Strategiesshould also include educating healthcareproviders about unique triggers of PAHin their patient populations, such asenvironmental exposures, substance abuse,and comorbidities and associatedconditions. Furthermore, education shouldfocus on emphasizing the frequentoccurrence of PAH/PH in left heart disease,chronic lung disease, sleep-disorderedbreathing, cirrhosis, drug abuse, and HIVinfection. Strategies that allow for timelyreferral of patients with suspected PAH/PH
to a specialist should be identified andemphasized. Last, strategies should bedeveloped to make insurance companiesaware that advanced treatment methods,although expensive upfront, will pay off inthe long term in the form of reducedadmissions, emergency department visits,and overall healthcare use. For example,several PAH medications have been shownin studies to reduce hospitalizations anduse of expensive healthcare resources(110–112). The Pulmonary HypertensionAssociation’s Early Diagnosis Campaign isaddressing many of these issues for thegeneral population; this existing frameworkcould be modified to specifically address theneeds and challenges of providers andemergency room physicians in areas withlarge numbers of minority patients.
There is also evidence that socioculturaldifferences between patient and providerinfluence communication and clinicaldecision making (113). Evidence suggeststhat provider–patient communication isdirectly linked to patient satisfaction,adherence, and subsequently, healthoutcomes (102). The gaps that are presentin physician understanding of healthdisparities include lack of time, difficultywith a language barrier, no formal trainingin health disparities education, andpersonal biases that can affect judgment inthe decision-making process. Socioculturalfactors are critical to the medical encounter,yet cross-cultural curricula have beenincorporated into undergraduate, graduate,and continued health professions educationonly to a limited degree (114). A meta-analysis conducted by the Agency forHealthcare Research and Quality,consisting of a systemic review of 91 articlesthat measured the impact of culturalcompetence training on the quality of careprovided to minority patients, found thatthis training yielded improvement inprovider knowledge, attitudes, and skillsin this area, as well as improvements inpatient satisfaction (115). Cross-culturaltraining of healthcare providers alsoprovides a medium for educating providerson how to interact with minorities (114,116, 117). In particular, technology-basedlearning (e-learning) is a powerful andeffective tool for cross-cultural education atall levels (115). It allows for extensivetraining of a large group of learners in ashort amount of time to achieve a uniformset of skills (115). In the current healthcareenvironment of limited time and financial
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resources, e-learning provides an excellentmechanism for extensive, high-qualitycross-cultural education for medicalstudents, residents, and practicingclinicians (115). However, there have beenchallenges to cross-cultural curricula, withresistance to curricula that are viewed as“soft” or lacking an evidence base (116). Toenhance and improve the medicaleducation curriculum, it is critical andnecessary to expose medical students to freeclinics, underserved populations, and healthdisparities in a community (118). Oneexample of how this can be performed wasprovided by a study that evaluated whetherquality improvement interventions improvecare and outcomes for minority patientssuffering from depression (119). This studyrandomized 46 primary care practices tousual care or a quality improvementprogram. Providers in the interventiongroup were exposed to trained local expertswho educated clinicians and taughtworkshops on depression treatmentmodels. Participating clinicians alsoreceived written manuals, and access tomonthly lectures and meetings (119). Inaddition, intervention group providers wereexposed to trained local psychotherapistswho provided cognitive behavioral therapy,and trained local nurses to serve asdepression specialists to educate, assess, andmonitor patients. Last, the interventiongroup also included a workshop whereparticipants received materials (written andvideo) to educate patients (119). Allmaterials were in English and Spanish, andLatino and African American providerswere featured in the educational videos.Providers received information regardingcultural beliefs and ways of overcomingbarriers (119). A secondary aim of thisstudy was to ensure inclusion of minorities.The results demonstrated that patients inthe intervention group were more likelythan control subjects to receive counselingor use antidepressants (50.9 vs. 39.7%; P,0.001) and less likely than control subjectsto meet criteria for depression (39.9 vs.49.9%; P = 0.001) (119). Thus, healthdisparities education could improveprovider–patient communication and helpeliminate the pervasive racial disparitiesseen in medical care today (120).
Patient EducationThe population groups within whichdisparities exist are multidimensional.Perhaps the most historically studied and
legislatively focused, however, have beenpopulation groups defined by race andethnicity. In 2002, the Institute of Medicineissued a report, Unequal Treatment:Confronting Racial and Ethnic Disparities inHealth Care, which concluded that racialand ethnic minorities tend to receive alower quality of healthcare thannonminorities (121). This report set out toassess the extent of racial and ethnicdifferences in healthcare, and to evaluatethe potential role of bias, discrimination,and stereotyping at the level of thepatient–provider interaction as well as atthe institutional and health system levels.
The role of the interaction between thehealthcare provider and patient has beendescribed as a crucial source of healthcaredisparity. As we start from the perspective ofthe patient, it has been described thatminority patients are more likely to followmedical advice if the treating physician is alsofrom a minority background (104). In thestudy by Cooper-Patrick and colleagues(104), when adjusted for patient age, sex,education, marital status, health status, andlength of visit, patients rated their recentprimary care visit as more participatory withrace-concordant physicians than with race-discordant physicians. In turn, patientsatisfaction was highly associated withparticipatory decision making. In a KaiserNorthern California study, identifiedpredictors for patient–physician raceconcordance included patients’ ability tochoose their physician, limited Englishproficiency, and availability of minorityphysicians, particularly for AfricanAmerican and Hispanic groups (122). Thissuggests that, if available, patients tend tochoose their physician based on similar raceand language proficiency. Reasons forpatients to trust and seek out a physician of asimilar race or ethnicity include concernsregarding communication and decreasingthe language barrier, as well as the increasedlikelihood of empathic treatment and jointdecision making if a patient’s physicianshares the same background (123).
In addition to the patient–physicianinteraction, health and healthcaredisparities stem from more global andsystemic barriers to providing care. In astudy by Morrison and colleagues, in arandom selection of 30% of New York Citypharmacies, only 25% of nonwhiteneighborhood pharmacies supplied asufficient amount of opioids to treat severepain, compared with 72% of white
neighborhood pharmacies (124). Moreover,the use of professional interpreters isassociated with improved patientunderstanding of disease and appears toraise quality of clinical care fornon–English-speaking patients toward thelevel of care for patients without languagebarriers (125, 126). At present, there arepolicy and governmental forces in place tolegislate for improvement in more equalaccess to care and services such as languageservices. As an example, in 2010, HHSestablished the HHS Disparities ActionPlan to reduce racial and ethnic healthdisparities. This called for increasedfunding for availability of influenzavaccinations to uninsured populations,increased numbers of grants available formore data collection on the health ofvulnerable populations, and the provisionof blueprints and standards for healthcareorganizations to implement culturally andlinguistically appropriate services (127).
Patient education can be achievedthrough the provision of educational materialin languages other than English, ideally freeof charge. Patients are often hesitant to reportsymptoms, and a paternalistic approach tomedicine may still be prevailing. To alleviatethis, the PHA existing toolkit for self-advocacy should be refined to better servethese patients, thus enabling patients to askbetter disease-specific questions throughbetter understanding of their disease process.Community outreach can raise awarenessthrough health fairs that not only educateabout the disease, but also target subspecialists(pulmonologists/cardiologists). However, todo so, there must be a concerted effort andsupport from local governments and majorprofessional societies alike (101, 128).
Health PolicyIn 2000, the Minority Health and HealthDisparities Research and Education Act of2000, the first major legislation focused onreduction of disparities, created the NationalInstitute on Minority Health and HealthDisparities (NIMHD) within the NIH. Thevision of the NIMHD is “an America in whichall populations will have an equal opportunityto live long, healthy, and productive lives.” Toaccomplish this, the NIMHD raises nationalawareness about the prevalence and impact ofhealth disparities and disseminates effectiveindividual-, community-, and population-levelinterventions to reduce and encourageelimination of health disparities (129). Thework of the NIMHD to improve inclusion of
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health disparity concerns in research includesa strategic plan that focuses on three keyelements to be considered at all NIH centers:(1) conduct and support intensive research onthe factors underlying health disparities; (2)expand and enhance research capacity to createa culturally sensitive and culturally competentworkforce; and (3) engage in aggressive,proactive community outreach, informationdissemination, and public health education.
In 2011, in collaboration with theNIMHD, the Department of Health andHuman Services developed the HHS ActionPlan to Reduce Racial and Ethnic HealthDisparities. The HHS Disparities Action Plansets out a series of priorities, strategies,actions, and goals to achieve its vision of “anation free of disparities in health and healthcare.” Within the department, the Office ofMinority Health is charged with advancingthe goals of the HHS Disparities Action Plan:
d Transform healthcared Strengthen the nation’s health and
human services infrastructure andworkforce
d Advance the health, safety, and well-being of the American people
d Advance scientific knowledge andinnovation
d Increase the efficiency, transparency, andaccountability of HHS programs
An executive summary of progress todate has highlighted the achievements thusfar, to include support of Medicaidexpansion under the Affordable Care Act(ACA); support of the CMS program, Careto Coverage; and expanded efforts to informboth patients and healthcare providers ofcoverage opportunities and identify specificcovered programs of benefit to the enrollees.The action plan has also supported efforts atincreasing transparency such that data canbe accessed to track changes in these healthsystem characteristics over time and toidentify areas that require improvementthrough the Health System MeasurementProject. Important provisions in the ACAtarget health disparities beyond coverageopportunities for uninsured. These effortsmirror those outlined in the HHSDisparities Action Plan above. Importantly,under the ACA, the rates of uninsured havefallen the most in African American andHispanic populations. African Americansare much more likely than white personsto fall into the coverage gap in the statesthat have not expanded Medicaid underthe ACA.
Regional, state, and local efforts atlimiting health disparities are key indecreasing health disparities through localefforts using regional and community-focused interventions. These localinterventions can be broad, addressing aregion or state; or focused, addressing healthdisparities in a single neighborhood. Grantspreviously funded through the CommunityTransformation Grants program with theCenters for Disease Control and Prevention,Division of Community Health, along withcurrently funded grants titled Racial andEthnic Approaches to Community Health(REACH) grants, have provided states, localhealth departments, universities, andnonprofit groups funds to support localefforts to address health disparities.Community-based foundations alsocontribute resources to developinginitiatives aimed at reducing disparities.
The PHA was created in 1991 bypatients with a need to connect with othermembers of the patient community. In 25years, the organization has grown to morethan 16,000 members nationally, with anannual budget of more than 12 milliondollars, and a research portfolio of over 17million dollars. Traditionally, the PHA hasfocused its advocacy efforts primarily onlegislative and grassroots activities. This hasplayed out both through the effortsdescribed above and those in support of thePulmonary Hypertension Research andDiagnosis Act, which the organization hasworked to pass at the federal level. ThePHA’s overall advocacy efforts havefocused on impacting patient outcomes,supporting work to find a cure and identifynew treatments, and also working toremove barriers, while the grassroots havefocused primarily on the PAH bill.
Throughout the organization’s history,members of the PHA’s medical and patientcommunities have lobbied members ofCongress for their support of the PH bill,and in favor of other legislation put forth bycoalitions of organizations in support ofspecific issues impacting patient care. Todate, efforts supporting the most PAH-specific of the PHA’s legislative priorities,passage of the Pulmonary HypertensionResearch and Diagnosis Act, have resultedin increased awareness among legislators ofPAH and the needs of the PAHcommunity, but have yet to result in thepassage of the target legislation. Thoseopposed state that they are averse todisease-specific legislation. Further, in a
climate of continued cutbacks in NIHfunding—NIH funding has either been cutor unable to outpace inflation in all but twoof the past 14 years—getting the bill passedhas proven difficult, even though thelegislation itself is budget neutral (130).Despite this resistance, the PHA remainscommitted to address minority-specificchallenges through PH Care for All, aninitiative that aims to identify and improveon gaps in early diagnosis and treatment forminorities living with PH. The goals of PHCare for All are as follows.
Expand legislative advocacy effort toinclude state and local leaders. Many of thedecisions most impacting the targetpopulation of PH Care for All are actuallymade at the state and local levels, ratherthan at the federal level. This is anadvantage, as it is typically easier to impactstate and local legislators via grassrootsefforts, as they are less removed from theirconstituents than their federal counterparts.PH Care for All could be most impactful atthis level by advocating for policies relatedto logistical issues in turn related todiagnostic and treatment access, such asbusiness hours of health clinics andservices, availability of interpreter servicesat health clinics, transportation subsidiesfor low-income patients, and so on. Inaddition, Medicare/Medicaid coverage andissues related to third-party payers aremore rightly addressed at this level.
Traditionally, the PHA’s state and localadvocacy efforts have been largely one-offand conducted by members of the PHAcommunity with varying degrees of success.Organized expansion in this directionwould likely call for the development of acore group of trained advocates; the PHAhas some infrastructure to support this, inthe form of more than 200 volunteerspassionate about advocacy. In addition, thePHA has forged a successful relationshipwith Women in Government, anorganization supporting female statelegislators. Engagement with thisorganization and others like it, includingthe National Conference of StateLegislatures, could potentially lead to anincreased impact at this level whilemaximizing the resources available to thePHA. Also, administrative advocacy willafford the PHA the opportunity toinfluence the rules and regulations thatshape a law as it is implemented. For thisreason, in addition to seeking amendmentto laws that are disadvantageous to the
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target population, attention should be givento new legislation intended to positivelyimpact minorities.
Recommendations
1. PAH registries must be organized toreliably capture informationconcerning race/ethnicity and SES ofpatients.
2. Genetic screening of large populationsshould include patients with PAHbelonging to minority groups andaddress the existence of unique geneticdeterminants.
3. SES should be included in the riskstratification to help identify patientswith PAH who may be at greatest riskfor noncompliance.
4. Hospitals, health insurers, andproviders should be educated on theimportance of data on key determinantsof health and encouraged to increasetheir efforts to collect data such as SESas well as race/ethnicity.
5. Partnership with public healthdivisions, community-based healthcenters, and existing heart failureoutreach programs should beencouraged to collect relevant dataconcerning adverse environmentalexposures and clinical outcomes onvulnerable PAH populations.
6. A cross-cultural curriculum should bemandatory and implemented early inmedical training. The PHA and other
patient-centered organizations, withthe help of specialists in the field,should develop more educationalresources for patients and providers inminority communities.
7. Cross-cultural competence needs to beframed as a skill set—similar to areview of systems, or checklist—thatcan help providers manage challengingcross-cultural cases. It must be seen as(a) practical, actionable, and timeefficient, (b) should be taught in a case-based fashion that creates clinicalchallenges, (c) must be linked toevidence-based guidelines and thepeer-reviewed literature, and (d) mustleave students with a concrete set oftools and skills.
8. Formal training courses should bedeveloped that address healthdisparities and cross-culturalcompetency through onlinetraining/modules for accreditation. Anideal educational program would targetboth providers and patients, and wouldneed to be tailored for PAH-specificneeds.
9. Increase awareness among physiciansregarding the impact of implicit orunconscious bias toward particularpopulation groups in the setting ofPAH.
10. Increase the amount of racial andethnic minority physicians in thehealthcare provider workforce topromote race- and language-
concordant patient–physicianinteractions.
11. Legislate governmental standardsregarding access to cultural- andlanguage-appropriate services across allhealthcare organizations.
Conclusions
PAH is a rare but devastating disease that, ifuntreated, is associated with reduced qualityof life and poor outcomes. Minorities in theUnited States are likely at high risk of pooroutcomes due to lack of proper access tohealthcare and limited resources to assistthem in living with the disease. The limitednumber of research studies to date hasslowed our progress in understanding theimpact of health disparities and thedevelopment of effective strategies toovercome these barriers to properhealthcare. Our proposed researchrecommendations represent the first effortto address these issues and improve thequality of care of this vulnerable population.Despite being limited to WHO group 1patients in the United States, this researchstatement is expected to serve as a platformfor discussions regarding the impact ofhealth disparities in any population andshould guide researchers to look into theircountry’s health system for barriers tohealthcare. We envision that anotherresearch statement could be prepared withthe collaboration of professionals fromaround the globe. n
This official statement was prepared by an ad hoc subcommittee of the Pulmonary Circulation Assembly.
Members of the subcommittee are asfollows:
VINICIO DE JESUS PEREZ, M.D. (Chair)ARUNABH TALWAR, M.D. (Co-Chair)JESSICA ARMSTRONG, B.A., M.A.RICHARD CHANNICK, M.D.LAURA HOYT D’ANNA, PH.D.KAREN FAGAN, M.D.JOE G. N. GARCIA, M.D.MICHAEL GRAY, B.SC., M.P.H.STEVEN M. KAWUT, M.D., M.P.H.TIM LAHM, M.D.ROBERTO MACHADO, M.D.STEPHEN MATHAI, M.D.MATTHEW MORENO, B.S.JOSANNA RODRIGUEZ LOPEZ, M.D.ERIK J. RODRIQUEZ, PH.D.SONU SAHNI, M.D.
MONA SELEJ, M.D.HALLEY TSAI, M.D.ROHAM T. ZAMANIAN, M.D.
Author Disclosures: A.T. served as a speakerfor Boehringer Ingelheim and served on anadvisory committee for Bayer HealthCarePharmaceuticals, Boehringer Ingelheim, andUnited Therapeutics Corporation. R.C. servedas a consultant for Bayer HealthCarePharmaceuticals. S.M.K. received grants fromActelion Pharmaceuticals US, Bayer HealthCarePharmaceuticals, Gilead Sciences, LungBiotech, and United Therapeutics Corporationfor continuing medical education. T.L. served asa consultant for Actelion Pharmaceuticals US,served on a scientific review committee forGilead Sciences, served as a speaker for BayerHealthCare Pharmaceuticals, and receivedresearch support from Bayer HealthCare
Pharmaceuticals and Eli Lilly. S.M. served as aconsultant for Actelion Pharmaceuticals US,Bayer HealthCare, and Gilead Sciences. J.R.L.received research support from ActelionPharmaceuticals US and served as a consultantfor Gilead Sciences. M.S. is a full-time employeeof Actelion Pharmaceuticals US. R.T.Z.received research support from ActelionPharmaceuticals US and United TherapeuticsCorporation; served as a consultant for ActelionPharmaceuticals US, Bayer HealthCarePharmaceuticals, and United TherapeuticsCorporation; served as a consultant for andowns stocks, stock options, or other equityinterests in Selten; and holds a patent for FK506for treatment of pulmonary arterial hypertensionwith Stanford University. V.d.J.P., J.A., L.H.D’A.,K.F., J.G.N.G., M.G., R.M., M.M., E.J.R., S.S.,and H.T. reported no relationships with relevantcommercial interests.
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