Breastfeeding is associated with a decreased risk of childhood asthma exacerbations later in life

Background: Breastfeeding has been suggested to influence the risk of asthma and asthma severity in children. However, the conclusions from epidemiologic studies are inconsistent. Methods: We used data from 960 children (aged 4-12 years) using regular asthma medication who participated in the PACMAN study. Breastfeeding exposure was based on questionnaire data and stratified into (i) ever vs never, and (ii) >= 6 vs < 6 months duration of breastfeeding. Asthma severity was based on the occurrence of asthma exacerbations in the preceding year and/or poorly controlled asthma symptoms during the last week of study visit. Odds ratios (ORs) were derived from univariate and multivariable logistic regression analyses. Results: Breastfeeding was associated with a decreased risk of asthma exacerbations; adjusted (adj.) OR: 0.55 (95% confidence interval [CI]: 0.35-0.87). After stratification for duration of breastfeeding, the adj. ORs were 0.48 (95% CI: 0.27-0.84) for duration < 6 months and 0.71 (95% CI: 0.43-1.20) for duration >= 6 months breastfeeding. When we stratified the analysis by family history of asthma, the association between breastfeeding and asthma exacerbations was strong and statistically significant only in children with a positive family history of asthma; adj. OR: 0.34 (95% CI: 0.18-0.66). There was no association between breastfeeding and risk of poor asthma control; adj. OR: 1.04 (95% CI: 0.76-1.41). Conclusion: In a pediatric population with asthma, children who had been breastfed had a statistically significantly lower risk of asthma exacerbations later in life compared to asthmatic children who had not been breastfed.