Are influences during pregnancy associated with wheezing phenotypes during the first decade of life?
OBJECTIVE
Recently, attention has focused on possible early life origins for asthma. We sought to identify whether factors present during pregnancy were associated with development of childhood wheezing phenotypes.


METHODS
A whole population birth cohort (n=1456) on the Isle of Wight, UK, was followed through to age 10 y. Where possible, information regarding environmental exposures and events during pregnancy was obtained from the maternity records (n=1238). Children were seen at ages 1, 2, 4 and 10 y, and wheezing symptoms were used to define wheezing phenotypes in the first decade (n=1034).


RESULTS
Risk of early-onsetpersistent wheeze (onset in the first 4 y, still present at age 10) was increased by environmental tobacco smoke exposure in pregnancy (OR=2.44; 95% CI: 1.37-4.34) plus maternal asthma (3.57; 1.84-6.94), but reduced by cat ownership (0.30; 0.13-0.62). Early transient wheeze (onset in the first 4 y, but not present at age 10) was increased by environmental tobacco smoke exposure (1.58; 1.02-2.45), male gender (1.68; 1.09-2.60) and low birthweight (3.65; 1.27-10.52). No environmental factors in pregnancy were associated with late-onset persistent wheeze (onset after age 4 y, still present at 10 y).


CONCLUSIONS
In addition to genetics, maternal exposures during pregnancy show association with childhood and especially early-life wheezing phenotypes.
Kurukulaaratchy
Ramesh J
RJ
David Hide Asthma & Allergy Research Centre, St Mary's Hospital, Newport, Isle of Wight, United Kingdom.
Waterhouse
Linda
L
Matthews
Sharon M
SM
Arshad
Sayed H
SH
D000818:Animals; D000829:Animals, Domestic; D001249:Asthma / Q000209:etiology* / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D010641:Phenotype; D011247:Pregnancy; D015995:Prevalence; D012135:Respiratory Sounds / Q000209:etiology* / Q000235:genetics; D012907:Smoking / Q000009:adverse effects; D006113:United Kingdom / Q000453:epidemiology