Study finds association between longer duration of exclusive breastfeeding and childhood asthma protections

A recent study published in Annals of Allergy, Asthma, and Immunology, the scientific journal of the American College of Allergy, Asthma, and Immunology (ACAAI) examined the effect of a longer duration of exclusive breastfeeding and protection against childhood asthma.

The study used prospective pregnancy cohorts in the ECHO PATHWAYS consortium—more than 2000 mother-child pairs—including the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study, the Infant Development and Environment study (TIDES), and the Global Alliance to Prevent Prematurity and Stillbirth (GAPPS). By combining studies, study investigators achieved demographic distribution, including 38% of Black respondents and 6% of Hispanic/LatinX respondents.

Women reported duration of any and exclusive breastfeeding and childhood asthma outcomes during study follow-up at child aged 4 to 6 years. “Outcomes included current wheeze (last 12 months), ever asthma, current asthma (having ≥2 of current wheeze, ever asthma, medication use in past 12-24 months) and strict current asthma (ever asthma with current wheeze and/or medication use in past 12 to 24 months),” wrote study investigators.

They used multivariable logistic regression to assess associations (odds ratios [OR] and 95% confidence intervals [95CI]) comparing breastfeeding and asthma outcomes—adjusting for potential confounders. Additionally, effect modification by mode of delivery, infant sex, and maternal asthma was assessed, according to the study.

Study results showed that women reported a 33% (0<2 months), 13% (2 to 4 months), 9% (5 to 6 months), and 45% (>6 months) duration of breast feeding had a protective linear trend with ever asthma but no other outcomes, investigators wrote.

The protective association of exclusive breastfeeding, and child outcomes showed to be duration-dependent, noted investigators, highlighting an example of “current asthma adjusted OR [95% CI]: 0.64 [0.41, 1.02], 0.61 [0.38, 0.98], and 0.52 [0.31, 0.87] for durations of 2-4, 5-6, and >6-months respectively, compared to <2 months.”

Of note, the protective associations in exclusive breastfeeding were stronger in dyads with children born vaginally vs cesarean delivery, however, the study reported interactions were not statistically significant.

Based on these results, investigators concluded that a longer duration of exclusive breastfeeding showed protective qualities against child asthma.

Reference:

Wilson K, Gebretsadik T, Adgent MA, et al. The association between duration of breastfeeding and childhood asthma outcomes. Annals of Allergy, Asthma & Immunology. Published online May 2022:S1081120622004008.