Impact of environmental exposures on asthma control in pregnancy

Abstract

JUDETTE LOUIS, NICHD MFMU Network, Bethesda, Maryland OBJECTIVE: To evaluate the impact of avoidance of environmental exposures on asthma control and treatment in pregnancy. STUDY DESIGN: This is a secondary analysis of a multicenter; prospective, observational cohort study conducted over 4 years at 16 academic hospital centers. The NAEPP classification was used to stratify patients by asthma severity. Environmental exposures included household smoking, pets, and use of a mattress cover. Indices of asthma control included percentage of symptomatic days and nights, activity restriction, and sleep disturbance. Indices of treatment included number of unscheduled visits, hospital admissions, asthma exacerbations, and use of steroids. Data were analyzed by chi-square, Wilcoxon rank sum and Cochran-Armitage trend test where appropriate. P!0.05 was significant. RESULTS: There were 1,812 asthmatics, 50% (906), were mild, 47% (851) were moderate and 3% (55) were severe asthmatics. Severe asthmatics that could identify 1 or R 2 asthma triggers had a lower rate of symptomatic days compared to those who did not know their triggers. (22.9% and 26.6% vs. 48.6%, p = 0.04) They also had less nights of sleep disturbance (7.3% and 19.2% vs. 28.8%, p = 0.02), were less likely to have an unscheduled visit (21.4% and 0.0% vs. 36.4%, p = 0.03 for trend) and less likely to have an asthma exacerbation during pregnancy (50% and 50% vs. 81.8%, p = 0.02 for trend). This association was not evident for mild and moderate asthmatics. In mild and moderate asthmatics, use of a mattress cover was associated with a decrease in sleep disturbance and fur bearing pets were associated with an increase in symptomatic days. Among mild and moderate asthmatics, avoidance of environmental exposures was not associated with any treatment indices. CONCLUSION: Avoidance of asthma triggers may improve daily symptoms and need for treatment for severe asthmatics. The findings are not as consistent for mild and moderate asthmatics.