To determine the prevalence of chronic bronchitis in young teenagers and its association with asthma, smoke exposure, and gastroesophageal reflux (GER). We hypothesized that chronic bronchitis would be stongly associated with asthma.
As part of the Phase III International Study of Asthma and Allergies in Childhood, 2397 children, 11-15 yrs-old (median 13 yrs) completed written and video respiratory-symptom surveys. We defined chronic bronchitis as - daily cough productive of phlegm for at least 3 months per year, current asthma symptoms as - wheeze within the past year and “yes in the past year” to one or more of the four asthma video scenarios, smoke exposure as - exposed to tobacco smoke at least several hours/day, and GER as - heartburn and/or regurgitation within the past week. We used multivariate logistic regression to examine the relationships between chronic bronchitis and the other conditions.
The prevalence of chronic bronchitis was 7.2%. Almost half of the patients with chronic bronchitis (82/173) had current asthma symptoms. Furthermore, many of the remaining 91 children had findings suggestive of asthma; 24% reported wheezing attacks and 22% had used an inhaler within the past year, while 21% had been diagnosed with asthma by a doctor. Current asthma was most strongly associated with chronic bronchitis, followed by GER, and smoke exposure (TableBronchitis n=173No Bronchitis n=2224*Odds ratio [95% CI]Current asthma82 (47%)214 (10%)6.4 [4.5-9.0]GER40 (23%)108 (5%)3.3 [2.1-5.1]Smoke exposure43 (25%)180 (8%)2.7 [1.8-4.1]*
Multivariate logistic regression incorporating current asthma, GER, smoke exposure, and gender).
In this group of young teenagers, many who met the criteria for chronic bronchitis also had current asthma symptoms. Most of chronic bronchitis in this population was likely due to asthma, but both GER and smoke exposure also contributed.
Children presenting with chronic bronchitis should be evaluated for asthma.
E.R. Carter, AstraZeneca Pharmaceuticals