Dobson DaVanzo & Associates, LLC Vienna, VA 703.260.1760 www.dobsondavanzo.com
Allen Dobson, PhD
Health Economist
Co-Founder & President
Dobson|DaVanzo & Associates, LLC
Dobson DaVanzo & Associates, LLC Vienna, VA 703.260.1760 www.dobsondavanzo.com
Discussion of Methods Used to Study
the Reduction in Health Care Cost
Through Dietary Supplements
PRESENTED TO: NHRI & ANA Symposium
PRESENTED BY: Al Dobson, PhD
October 28, 2011
Chicago
1
“Nutrition is an input to and foundation for health and development.”
Interaction of infection and malnutrition is well-documented.
Better nutrition means stronger immune systems, less illness and better health.
Healthy people are stronger, are more productive and more able to create opportunities to gradually break the cycles of both poverty and hunger in a sustainable way.
Better nutrition is a prime entry point to ending poverty and a milestone to achieving better quality of life.
World Health Organization
Introduction
2
• Update to Prior “Lewin Studies”:
• A Study of the Health and Cost Effects of Five Dietary
Supplements, 2004
• An Evidence-Based Study of the Role of Dietary Supplements
in Helping Seniors Maintain their Independence, 2006
• Methodological Limitations to Longitudinal Observational
Studies
Presentation Overview
3
Calcium with Vitamin D
Folic Acid
Omega-3 Fatty Acids
Lutein with Zeaxanthin
The Dietary Supplements Selected for
the “Lewin Studies” were…
4
Effect on Biological Markers
Cost Effects from Reduced
Health Care Utilization
Clinical Effects from Change in
Biological Markers
Effect on Biological Markers
Cost Effects from Reduced
Health Care Utilization
Clinical Effects from Change in
Biological Markers
Conceptual Framework for the Study
5
There is considerable evidence supporting:
the association of reduced bone loss and reduced fractures, with
the best evidence supporting a reduction in hip fractures
a reduction not only in the cost of the hospitalization to repair the
hip, but also the post-acute stay for some portion of patients
(about 25%) in a skilled nursing facility
Cost offsets result from the potential avoidance of approximately
776,000 hospitalizations for hip fractures over five years, as well
as avoided skilled nursing facility stays for some portion of
patients.
The five-year estimated net cost effect associated with avoiding
hip fracture is approximately $16.1 billion (savings to Medicare).
Key Findings: Calcium with Vitamin D
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Of the approximately 44 million American women who
are of childbearing age and not taking folic acid, if just
11.3 million began taking 400 mcg. of folic acid on a daily
basis periconceptionally, 600 babies would be born
without NTDs, saving as much as $344,700,000 in the first
year as a result.
Over five years, taking into account the cost of the
supplement, $1.4 billion could potentially be saved.
Key Findings: Folic Acid
7
The estimate of the five-year (2008-2012) potential net savings
from avoided transitions to dependency associated with a
reduction in the relative risk of age-related macular degeneration
(AMD) through daily intake of 6-10 mg of lutein with zeaxanthin is
$3.6 billion.
Across the five year period, approximately 190,927 individuals
could avoid the transition to dependence either in the community
or a nursing facility that would accompany a loss of central vision
resulting from advanced AMD.
Key Findings: Lutein with Z
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The estimate of the potential five-year (2008-2012)
savings in health care expenditures resulting from a
reduction in the occurrence of coronary heart disease
(CHD) among the over age-65 population through daily
intake of approximately 1800 mg of omega-3 is $3.2
billion.
Approximately 374,301 hospitalizations and associated
physician fees due to CHD could be avoided.
Key Findings: Omega-3 Fatty Acids
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Calcium and vitamin D reduce bone loss and/or osteoporosis,
especially among post-menopausal women
Folic acid reduces the occurrence of neural tube defects
(NTDs) if women consume the supplement before they
become pregnant, and continue to do so in the early stages of
pregnancy
Omega-3 fatty acids reduce the relative risk of coronary heart
disease (CHD)
Lutein with zeaxanthin reduces the risk of age-related
macular degeneration (AMD)
Literature Contains Broad Evidence Base
of Multiple Studies
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Why These 4 Supplements?
Levels of
Evidence
Opinions of expert based on experience
Single Case Report
Case Control study
Case Series
Cross sectional study
Cohort Study
RCT
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Gross Cost
� Size of the at-risk population (Medicare Trustees Report)
� Cost of supplement
� Take up rate
Benefit
� Number of users achieving therapeutic effect
� Reduction in health service utilization
Net Savings (2008-2012)
� Net Savings = Benefits less Costs
Study Methods - Cost EstimationCBO Scoring Methodology
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• Generalizability
• Loss to follow up and missing data
• Repeated measures on same individual
• Measurement at varying time points from symptom
onset
• Assessing effect of treatment
Methodological Limitations of
Longitudinal Observational
Studies
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• Source of cases
• True population based, catchment population, or consecutive
series
• Timing of recruitment:
• First presentation of disease, or prevalent cases
• Inclusion criteria:
• Classification criteria, age, ethnicity
Evaluating Longitudinal
Observational Studies
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• Analyses:
• Methods and rationale
• Power to detect clinically meaningful change
• Handling of missing data
• Tests of internal and external validity
• Temporal effects
• Causality
Evaluating Longitudinal
Observational Studies (continued)
15
Methodological Evaluation for
Two Recent Studies. . .
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Criteria Mursu, 2011
Total Mortality with
Multivitamins
Klein, 2011
Risk of Prostate Cancer with
Vitamin E
Methods & Rationale Cox Proportional Hazard
Model
Proportional Hazard Model
Power to Detect Meaningful
Change√ √
Handling of Missing Data 40.2% deceased during study Not clear
Tests of Internal & External
Validity
White women only – results
not confirmed in literature
Interactions confound results
of treatment in each group
Temporal Effects Follow-up 22 years –
repeated measure
Follow-up of 7 – 12 years
Causality No No biological explanation
Single Study √ √
A growing body of scientific research is beginning to provide
important clues about how diet choices affect health. In some areas,
the relationship between specific foods or dietary supplements and
particular health outcomes is fairly clear; in other cases, more
research is needed.
The rapid expansion of the population age 65 and older has a number
of economic implications. The people in this group, about 18 percent
of the population, account for about 30 percent of all health care
expenditures.
Conclusions
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Dobson DaVanzo & Associates, LLC Vienna, VA 703.260.1760 www.dobsondavanzo.com
Discussion of Methods Used to Study
the Reduction in Health Care Cost
Through Dietary Supplements
PRESENTED TO: NHRI & ANA Symposium
PRESENTED BY: Al Dobson, PhD
October 28, 2011
Chicago
18
Dobson DaVanzo & Associates, LLC Vienna, VA 703.260.1760 www.dobsondavanzo.com
Nutrition
Break