Relevant, biased or confounded results? Relevant, biased or confounded results?

Associations of Associations of environmental noiseenvironmental noise and and respiratory symptomsrespiratory symptoms in the in the

National Childrens´ Respiratory Survey (OGYELF), National Childrens´ Respiratory Survey (OGYELF), Hungary, 2005Hungary, 2005

Mihály János VarróMihály János Varró11, Zsolt Lang, Zsolt Lang22, , Anna PáldyAnna Páldy11, Mária Bényi, Mária Bényi33, Gizella Nádor, Gizella Nádor11, ,

János MartinJános Martin44, Gergely Tulipánt, Gergely Tulipánt44, , Anna MácsikAnna Mácsik11, Eszter Szabó, Eszter Szabó11, Péter Rudnai, Péter Rudnai11

11National Institute of Environmental Health, Budapest, HungaryNational Institute of Environmental Health, Budapest, Hungary22Nomogram Ltd., Budapest, HungaryNomogram Ltd., Budapest, Hungary33National Center for Healthcare Audit and Improvement, Budapest, HungaryNational Center for Healthcare Audit and Improvement, Budapest, Hungary44National Institute of Occupational Health, Budapest, HungaryNational Institute of Occupational Health, Budapest, Hungary

Former survey series: 1995–2002Former survey series: 1995–2002

– – Nat. Inst. Environ. Health (Budapest, Hungary): Nat. Inst. Environ. Health (Budapest, Hungary):

7–11 year old children (n~20,000)7–11 year old children (n~20,000)

– – Standardized questionnaire Standardized questionnaire

environmental health survey countrywideenvironmental health survey countrywide

(base: CESAR study; in more years:(base: CESAR study; in more years:

anthropometric, spirometric etc. measures)anthropometric, spirometric etc. measures)

– – Results: ISEE conferences alsoResults: ISEE conferences also

– – One of the questionnaire questions:One of the questionnaire questions:

flat: near heavy traffic flat: near heavy traffic

(associations with health endpoints)(associations with health endpoints)

„„Street with heavy traffic”; components:Street with heavy traffic”; components:

– – Physical:Physical: noisenoise, vibration, vibration

– – Chemical:Chemical: air pollutantsair pollutants: NO: NO22, CO, PM..., CO, PM...

– – Biological:Biological:polluted polluted modified pollen modified pollen

(may become allergenic)(may become allergenic)

WHO Pan-European Housing & Health Study WHO Pan-European Housing & Health Study

– – In 8 European town (in Budapest also)In 8 European town (in Budapest also)

–– Noise: associations with many health endpoints Noise: associations with many health endpoints

NoiseNoise

– – Stress reaction; neuroimmune mechanismsStress reaction; neuroimmune mechanisms

New questionnaire study: 2005New questionnaire study: 2005

– – Primary schools in the Primary schools in the whole country:whole country:

pupils in 3rd grade classes pupils in 3rd grade classes ((>>10 children10 children/class)/class)

– – Postal delivery Postal delivery

(into 2726 schools, 100,333 questionnaires); (into 2726 schools, 100,333 questionnaires);

parental completion (voluntary); parental completion (voluntary);

sending back by: post/local medical officerssending back by: post/local medical officers

– – Main question groups: Main question groups:

analogous to the former onesanalogous to the former ones

(demographical data, perinatal factors, health (demographical data, perinatal factors, health

endpoints,endpoints,

parameters of the built environment, parameters of the built environment,

lifestyle and social factors)lifestyle and social factors)

– – Analogous and new questions; Analogous and new questions; noise: noise:

(1) Not disturbing [base](1) Not disturbing [base]

(2) Slightly disturbing (2) Slightly disturbing

(3) Disturbs sleep as well(3) Disturbs sleep as well

ResultsResults

– – From 2,160 schoolsFrom 2,160 schools (79.2%) (79.2%)

62,711 questionnaires 62,711 questionnaires were sent back were sent back

((76.4% 76.4% of the questionnaires of the questionnaires

sent to the participating schools) sent to the participating schools)

– – Respiratory symptoms:Respiratory symptoms:

fast evaluation: fast evaluation:

End of 2005; GISEnd of 2005; GIS

Asthmatic symptoms Asthmatic symptoms

– – Data entry (still in process; Data entry (still in process;

now more than 40,000 questionnaires)now more than 40,000 questionnaires)

Methods of the 2nd phaseMethods of the 2nd phase

– – Data entry:Data entry: Epi Info v6.04dEpi Info v6.04d

– – Analysis:Analysis: STATA/W SE v9.2STATA/W SE v9.2

– – Associations of noise and Associations of noise and

respiratory (and allergic) respiratory (and allergic)

symptomssymptoms

METHODMETHOD SUBJ. GOODNESSSUBJ. GOODNESS

– – Logistic regressionLogistic regression X X

– – Logistic regressionLogistic regression XXXX

with robust variance estimation (one cluster variable)with robust variance estimation (one cluster variable)

– – Logistic regressionLogistic regression XXXXXXXX

with robust variance estimation (multistage)with robust variance estimation (multistage)

(( same ORs; different SEs) same ORs; different SEs)

(( different ORs; different SEs) different ORs; different SEs)

– – Random effects (+fixed effects) Random effects (+fixed effects)

logistic regression (one level) logistic regression (one level) XXXXXX

– – Random effects (+fixed effects) Random effects (+fixed effects)

logistic regression (multilevel) logistic regression (multilevel) X - - - - - - - -X - - - - - - - -

(GLLAMM; user-written; extremely slow)(GLLAMM; user-written; extremely slow)

(( STATA 9) STATA 9)

(( STATA 10; R?! / STATA 10; R?! /www.r-project.orgwww.r-project.org/)/)

– – Mixed effects logistic regressionMixed effects logistic regression XXXXXXXXXXXXXXXXXX

(multilevel)(multilevel)

Multistage variance estimationMultistage variance estimation

Sampling units Sampling units (not in the capital):(not in the capital):

– – Regions (NUTS-2)Regions (NUTS-2)

– – Counties (NUTS-3; not)Counties (NUTS-3; not)

– – Small areas (NUTS-4)Small areas (NUTS-4)

– – SettlementsSettlements

– – Schools (not! Schools (not!

~50% of the population: ~50% of the population:

1 school in 1 settlement) 1 school in 1 settlement)

Sampling units Sampling units (capital – not now; too few data e.):(capital – not now; too few data e.):

– – DistrictsDistricts

– – City parts (not); postal codes (not)City parts (not); postal codes (not)

– – SchoolsSchools

Methods of the 2nd phaseMethods of the 2nd phase (contd.) (contd.)

Adjustments:Adjustments:

– – Gender, age Gender, age (8 or 9 yrs) of the child;(8 or 9 yrs) of the child;

– – EthnicityEthnicity (Romany/not Romany)(Romany/not Romany)

– – Settlement sizeSettlement size (limits: ...5K...20K...50K…2M)(limits: ...5K...20K...50K…2M)

– – Nearby trafficNearby traffic (clean air; light -, heavy (clean air; light -, heavy

traffic)traffic)

– – Parents’ respiratory/allergic diseaseParents’ respiratory/allergic disease

– – Chest diseaseChest disease (0–2 year)(0–2 year)

– – Psychosomatic symptoms Psychosomatic symptoms (6 variables:(6 variables:sleep disorders, tiredness, attention disorders,sleep disorders, tiredness, attention disorders,

irritability, anxiety, sadness)irritability, anxiety, sadness)

Methods of the 2nd phaseMethods of the 2nd phase (contd.) (contd.)

AdjustmentsAdjustments (contd.): (contd.):

– – Factory inside of a 500 m radiusFactory inside of a 500 m radius

– – Housing estateHousing estate

– – Crowdness Crowdness (>1.5 person/room)(>1.5 person/room)

– – Mould in the flat, any timeMould in the flat, any time

– – ETSETS (>20 cig./day in the flat)(>20 cig./day in the flat)

– – Mothers’ education Mothers’ education

((<<8 elem. sch. classes; middle -, high 8 elem. sch. classes; middle -, high

school) school)

– – Sport Sport (only in the school; at home, too; officially)(only in the school; at home, too; officially)

– – Television: >2 hrs/dayTelevision: >2 hrs/day

– – Everyday’s living (hard/bad, middle, good/excellent)Everyday’s living (hard/bad, middle, good/excellent)

– – Social supportSocial support

Preliminary resultsPreliminary results

– – Data entry is in processData entry is in process

– – The majority of Budapest data: The majority of Budapest data:

laterlater

– – Multilevel mixed effect logistic modelsMultilevel mixed effect logistic models

are to be used laterare to be used later

ExclusionsExclusions

All: All: 41,765 41,765

Drops:Drops:

– – For not living at the same place from birth, For not living at the same place from birth,

– – Different school/home postal code,Different school/home postal code,

– – Budapest & single sample units,Budapest & single sample units,

– – More/less than 8–9 years old etc. More/less than 8–9 years old etc.

Altogether:Altogether: -27,560-27,560

________________________________________________________________________________________

Left:Left: 14,205 14,205

Demography:Demography:

– – Boys:Boys:

49.1%49.1%

– – Girls: Girls:

50.9%50.9%

– – 8 yrs olds:8 yrs olds: 36.8%36.8%

– – 9 yrs olds:9 yrs olds: 63.2%63.2%

– – Romany:Romany:

6.7%6.7%

– – Not Romany:Not Romany:

93.3%93.3%

By settlement size:By settlement size:

<5K:<5K: 38.1%38.1%

<20K: <20K: 31.7%31.7%

<50K:<50K: 15.6%15.6%

<1M:<1M: 14.6%14.6%

By traffic:By traffic:

– – Clean air:Clean air: 17.3%17.3%

– – Light traffic:Light traffic: 68.8%68.8%

– – Heavy traffic:Heavy traffic: 13.9%13.9%By noise:By noise:

– – Not disturbing:Not disturbing: 65.7%65.7%

– – Slightly disturbing:Slightly disturbing: 31.7%31.7%

– – Disturbs sleep as well:Disturbs sleep as well: 2.6%2.6%

Health outcomesHealth outcomes

– – Parents’ respiratory or allergic disease: Parents’ respiratory or allergic disease:

30.4%30.4%

– – Chronic Chronic bronchiticbronchitic symptoms: symptoms:

16.3%16.3%

– – AsthmaticAsthmatic symptoms (last 12 months): symptoms (last 12 months):

10.2%10.2%

– – Airway Airway allergyallergy::

16.0%16.0%

StratifyingStratifying

– – Parents’ respiratory or Parents’ respiratory or

allergic disease,allergic disease,

– – Traffic:Traffic:

quite similar resultsquite similar results

Hill’s criteria of causation and their application hereHill’s criteria of causation and their application here

Strength Strength – The possibility of causation– The possibility of causation

ConsistencyConsistency – Other investigations– Other investigations

(–)(–) SpecificitySpecificity – +/-– +/-

Temporal relationshipTemporal relationship – Necessary – Necessary

(Time series, Madrid, Spain;(Time series, Madrid, Spain; here: living at the same place…)here: living at the same place…)

Biological gradientBiological gradient – Dose-response relationship– Dose-response relationship

– Grades of exposition– Grades of exposition

?? Biological plausibility and coherenceBiological plausibility and coherence

– – Knowledges… a new challenge?Knowledges… a new challenge?

?? ExperimentExperiment

– – On animals; on humans: ethics?!On animals; on humans: ethics?!– – Ex juvantibus (indirect)Ex juvantibus (indirect)

SuggestionsSuggestions

– – Further analyses and investigationsFurther analyses and investigations

– – (Data entry completing)(Data entry completing)

– – Personal noise measurements in a survey?Personal noise measurements in a survey?

– – Clinical essays?Clinical essays?

– – On-line noise monitors; On-line noise monitors; spectral analysis?spectral analysis?

(Madrid, Spain)(Madrid, Spain)

– – Preventive measuresPreventive measures

– – Favourable effect of harmonic musicFavourable effect of harmonic music

SummarySummary

–– Nat. Childrens´ Respir. Survey (OGYELF), Nat. Childrens´ Respir. Survey (OGYELF), Hungary, 2005Hungary, 2005

– – AltogetherAltogether ~63,000 questionnaires ~63,000 questionnaires

–– Noise:Noise: 31.7%31.7%: slightly disturbing, : slightly disturbing,

2.6%2.6%: disturbs sleep as well: disturbs sleep as well

–– Logistic regression models, Logistic regression models,

with multistage variance estimation with multistage variance estimation

– – Bronchitic, asthmatic and allergic symptoms: Bronchitic, asthmatic and allergic symptoms:

– – aORs: 1.09**…1.28***, 1.47***…2.22***aORs: 1.09**…1.28***, 1.47***…2.22***

– – Personal noise measurements (survey); clinical essaysPersonal noise measurements (survey); clinical essays

– – On-line noise monitors; On-line noise monitors; spectral analysisspectral analysis

– – Preventive measuresPreventive measures

– – Favourable effect of harmonic musicFavourable effect of harmonic music

SummarySummary

Relevant, biased or confounded results?Relevant, biased or confounded results?

– – Seems notSeems not to be biased to be biased

– – Seems notSeems not to be confounded to be confounded

– – Seems Seems to be relevant – ? to be relevant – ?

ThanksThanks

– Ministry of Health:Ministry of Health: financial background;financial background;– Office of the Chief Medical Officer, Office of the Chief Medical Officer,

Leaders of the National Institute of Environmental Health (NIEH):Leaders of the National Institute of Environmental Health (NIEH):support of the study; support of the study;

– The directors and teachers of the cooperating schools:The directors and teachers of the cooperating schools:the succesful process of the survey; the succesful process of the survey;

– Parents: Parents: the correct fill-in of the questinnaires;the correct fill-in of the questinnaires;– Territorial institutes of Nat. Publ. Health and Med. Officer Service: Territorial institutes of Nat. Publ. Health and Med. Officer Service:

help in harvesting the questionnaires;help in harvesting the questionnaires;– All co-workers of the Dept. of Environmental Epidemiology, NIEH:All co-workers of the Dept. of Environmental Epidemiology, NIEH:

(Erzsébet Fleinek, Katalin Garancsy, Renáta Szentmihályi, (Erzsébet Fleinek, Katalin Garancsy, Renáta Szentmihályi, Tamás Rudnai, Dr. Endre Sárkány, Györgyi Tóth):Tamás Rudnai, Dr. Endre Sárkány, Györgyi Tóth):

conscious and hard workconscious and hard work

Thank you Thank you for for your your attention!attention!

E-mail: E-mail: varro.mihaly@oki.antsz.huvarro.mihaly@oki.antsz.hu