baltimore asthma intervention trial
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Baltimore Asthma Intervention Trial. Patrick N. Breysse, PhD Professor and Director Division of Environmental Health Engineering Department of Environmental Health Sciences Johns Hopkins Bloomberg School of Public Health Associate Director - PowerPoint PPT PresentationTRANSCRIPT
Baltimore Asthma Intervention Trial
Patrick N. Breysse, PhDProfessor and Director Division of Environmental Health
EngineeringDepartment of Environmental Health Sciences
Johns Hopkins Bloomberg School of Public Health
Associate DirectorCenter for Childhood Asthma in the Urban Environment
Centers for Children’s Environmental Health
Co sponsored by NIEHS, EPA, CDC
Johns Hopkins Center for the Asthmatic Child in the Urban
Environment (CCAUE)
Director: Peyton A. Eggleston, MD Associate Director: Patrick Breysse, PhD
Tim Buckley, PhD
Gregory Diette, MD, MS
Sukon Kanchanaraska, PhD
Jerry Krishnan, MD
Elizabeth Matsui, MD
Sekhar Reddy, PhD
Arlene Butz, RN, DSc
Cynthia Rand, PhD
Marsha Wills-Karp, PhD
Steve Georas, MD
Investigators
Why Focus on Asthma?
• In 1999…– 10,488,000 persons with asthma in US (3.8%)– 14.5 million work days lost with asthma– 3,114,000 children < 14 yrs old with asthma (4.9%)– 14 million lost school days– 14.6% report activity limited by asthma– 10,808,000 physician visits– 1,997,000 ER visits for acute asthma– 478,000 hospitalizations for asthma– 4657 deaths
CDC MMWR March 29, 2002 / 51(SS01);1-13
CCAUE
• Multidisciplinary research center
• Combine basic research and community based studies
• Long Term Goals– Understand mechanism by which allergens,
pollutant increases airway inflammation and asthma morbidity
– Develop effective intervention strategies
Environmental Factors in Urban Asthma Research Model
RESPIRATORYMORBIDITY
SUSCEPTIBILITY FACTORSATOPY, INFLAMMATION CONTROL
BRONCHIAL HYPERRESPONSIVENESS
ASTHMATICAIRWAY
OBSTRUCTION
AIR POLLUTANTS
ALLERGENS
CHILDREN LIVINGIN URBAN
ENVIRONMENTS
UNDERLYING SOCIAL SUSCEPTIBILITY FACTORS POVERTY, STRESS, CONFLICTING NEEDS, EDUCATION, ADHERENCE, ACCESS TO CARE
IMMUNOLOGIC SENSITIZATION
CCAUE Study Components
• Community Based Studies– Cohort Study of Environmental Asthma
• Longitudinal comparison of environmental exposures and other risk factors
• Greg Diette et al.
– Asthma Susceptibility to Particulates, Allergens • Genetic association of environmental exposures and asthma• Greg Diette et al.
– Asthma Intervention Trial• Randomized trial to reduced household exposures to
particulate matter and allergens• Peyton Eggleston et al.
CCAUE Study Components
• Basic Biologic Research– Genetics of Response to Ozone
• Mouse model examining genetic basis of Ozone and endotoxin inflammation
• Sekhar Reddy, Steve Kleeberger– Inflammatory Response to Particulate Matter
• Mouse model comparing susceptible and non-susceptible strains
• Compare indoor and outdoor particulate matter• Marsha Wills-Karp
– Dendritic Cell Response to Particulate Matter• In vitro response of cultured dendritic cells• Steve Georas
CCAUE Community Outreach
• Community Advisory Committee– 9 members representing political
organizations, schools, churches, parents
• Advisory Functions– Protocol feasibility– Community priorities, concerns– Translation of results to local community
387 children enrolled in asthma education
program
180 eligible andinterested
13 ineligible 42 refused or unable to contact
125 consented, questionnaire completed
116 baseline home evaluation
100 randomized
97 competed 1 year study
6 refused or unable to contact
16 failed scheduled visits3 moved out of area
3 dropped out of study
93 ineligible44 refused
Recruitment
CCAUE – Asthma Intervention Study
• Randomized Controlled Trial of Home Exposure Control in Asthma
• Rationale– Strong epidemiologic evidence that indoor
environmental exposure relates to asthma morbidity– Effective treatments available for indoor
environmental exposure • Goal
– Test hypothesis that reduction of allergen and pollutant exposure in the homes of asthmatic children will reduce morbidity
STUDY AREA
Air monitoring station
Recruitment Plan
• 100 children recruited from elementary schools in inner city neighborhoods
• Eligibility:
– 6 – 12 years old– Doctor-diagnosed asthma– Current asthma symptoms – No other lung disease – Live in catchment area
Intervention Protocol
questionnaireskin test
serum,FEV1
home environment
telephone
0 3 6 9 12
BASELINE
CONTROL
TREATMENT
TREATMENT
INTERVENTION
Intervention
• 3-4 home visits by home health educators
• Roach extermination, sealed plastic containers
• Allergen-proof bedding encasings
• HEPA air cleaner in child’s bedroom
• Smoking cessation education and support
Air Cleaner
Environmental Monitoring
• Indoor Air Pollutants were measured over a 72-hr period in child's bedroom– Particulate Matter
• PM10
• PM2.5
• Data-logging Nephelometer
– Ozone– Nitrogen Dioxide– Airborne nicotine (marker for passive smoking
exposure)
In-Home Air Sampling Set-Up
0
0.2
0.4
0.6
0.8
1
1.2
1.4 1
6:34
:30
18:
21:3
0
20:
08:3
0
21:
55:3
0
23:
42:3
0
01:
29:3
0
03:
16:3
0
05:
03:3
0
06:
50:3
0
08:
37:3
0
10:
24:3
0
12:
11:3
0
13:
58:3
0
15:
45:3
0
17:
32:3
0
19:
19:3
0
21:
06:3
0
22:
53:3
0
00:
40:3
0
02:
27:3
0
04:
14:3
0
06:
01:3
0
07:
48:3
0
09:
35:3
0
11:
22:3
0
13:
09:3
0
14:
56:3
0
16:
43:3
0
18:
30:3
0
20:
17:3
0
22:
04:3
0
23:
51:3
0
PM
Co
nc
(mg
/m3)
Outdoor
Indoor
Central Site
Comparison of Indoor, Outdoor at the Home, and Outdoor Central Site Particulate Matter
Reservoir Dust Allergen Samples
• Vacuum samples collected in bedroom, living room/family room, and kitchen– Analyzed for
• Cockroach• Dust mite• Cat• Dog• Mouse
Baseline Characteristics
CONTROL TREATMENT
Age (mean) 8.3 8.5
home ETS (%) 65 73
Cockroach (%) 66 62
Pos skin test (%) 65 75
Mod/severe syx (%) 20 28
controller meds (%) 34 28
FEV1 (% pred) 94±21 101±20
ED visit/3 mon (%) 36 32
Housing CharacteristicsCharacteristic % Characteristic %Row House 91 Leaks in bedroom 18
Roof Leaks 24 Food in bedroom 29
Cats 26 Cockroaches in bedroom 8
Dogs 20 Mouse droppings in bedroom
7
Current smoker 46
Moisture damage in kitchen 22
Cockroaches in kitchen 31
Mouse droppings in kitchen 38
0
10
20
30
40
50
60
baseline 6 mon 12 mon
Median Particulate Concentrations
g/m3(median)
PM10 treatment PM 2.5 treatment PM 10 control PM 2.5 control
-50
-40
-30
-20
-10
0
10
20
baseline 6 months 12 months
% c
ha
ng
e f
rom
ba
se
lin
e
PM10 treatment PM 2.5 treatment PM 10 control PM 2.5 control
p<0.001
p<0.001
p=0.08
p=0.019
Particulate Concentrations:% Change
PM10 treatment PM 2.5 treatment PM 10 control PM 2.5 control
Bedroom Cockroach Allergen
1
10
base 6 mon 12 mon
Bla g 1U/gm
p=0.07p=0.001
TreatmentControl
Proportion of children with wheeze, cough, dyspnea in last 2 weeks
-40
-30
-20
-10
0
10
20
30
40
base 3 mon 6 mon 9 mon 12 monCh
ang
e in
pro
po
rtio
n w
ith
sym
pto
ms
Treatment group
Control group
p=<0.001
p=0.60p=<0.001 p=0.02
Other Health Outcomes
• Other health outcomes not different between the two groups– Nighttime symptoms– ED visits– Hospitalizations
– FEV1
Summary
• A global environmental intervention was able to reduce levels of PM10, PM2.5 and cockroach allergen in inner city homes
• There was an associated reduction in symptoms in asthmatic children living in the homes
• Persistence of reduction is uncertain
Acknowledgements
• In addition the investigators previously mentioned– Chris Beck - Nowella Durkin– D’Ann Williams - Mayme Grant– Jean Curtin-Brosnan - Craig Lewis – Lee Swartz - Jennette
Logan– Barry Merriman - Zina Nettles-Smith – Karen Callahan - Dena Scott