A methodology to establish a database to study gene environment interactions for childhood asthma.
BACKGROUND
Gene-environment interactions are likely to explain some of the heterogeneity in childhood asthma. Here, we describe the methodology and experiences in establishing a database for childhood asthma designed to study gene-environment interactions (PAGES--Paediatric Asthma Gene Environment Study).


METHODS
Children with asthma and under the care of a respiratory paediatrician are being recruited from 15 hospitals between 2008 and 2011. An asthma questionnaire is completed and returned by post. At a routine clinic visit saliva is collected for DNA extraction. Detailed phenotyping in a proportion of children includes spirometry, bronchodilator response (BDR), skin prick reactivity, exhaled nitric oxide and salivary cotinine. Dietary and quality of life questionnaires are completed. Data are entered onto a purpose-built database.


RESULTS
To date 1045 children have been invited to participate and data collected in 501 (48%). The mean age (SD) of participants is 8.6 (3.9) years, 57% male. DNA has been collected in 436 children. Spirometry has been obtained in 172 children, mean % predicted (SD) FEV1 97% (15) and median (IQR) BDR is 5% (2, 9). There were differences in age, socioeconomic status, severity and %FEV1 between the different centres (p≤0.024). Reasons for non-participation included parents not having time to take part, children not attending clinics and, in a small proportion, refusal to take part.


CONCLUSIONS
It is feasible to establish a national database to study gene-environment interactions within an asthmatic paediatric population; there are barriers to participation and some different characteristics in individuals recruited from different centres. Recruitment to our study continues and is anticipated to extend current understanding of asthma heterogeneity.
Academic Child Health, University of Aberdeen, Aberdeen, UK. s.w.turner@abdn.ac.uk
Stephen W
SW
Turner
Jon G
JG
Ayres
Tatiana V
TV
Macfarlane
Anil
A
Mehta
Gita
G
Mehta
Colin N
CN
Palmer
Steve
S
Cunningham
Tim
T
Adams
Krishnan
K
Aniruddhan
Claire
C
Bell
Donna
D
Corrigan
Jason
J
Cunningham
Andrew
A
Duncan
Gerard
G
Hunt
Richard
R
Leece
Una
U
MacFadyen
Jonathan
J
McCormick
Sally
S
McLeish
Andrew
A
Mitra
Deborah
D
Miller
Elizabeth
E
Waxman
Alan
A
Webb
Slawomir
S
Wojcik
Somnath
S
Mukhopadhyay
Donald
D
Macgregor
D001249:Asthma / Q000235:genetics* / Q000503:physiopathology; D002648:Child; D004247:DNA / Q000032:analysis; D003625:Data Collection / Q000379:methods*; D016208:Databases, Factual; D030541:Databases, Genetic; D004777:Environment; D005260:Female; D005541:Forced Expiratory Volume; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D010641:Phenotype; D011788:Quality of Life; D012959:Socioeconomic Factors; D013147:Spirometry; D011795:Surveys and Questionnaires
D004247:DNA