The association between breastfeeding practices and acute chest syndrome among children with sickle cell disease
Brandi Pernell, Jessy Deshane, Alan Tita, Monica BaskinAbstract
Background
Acute chest syndrome (ACS) heavily contributes to pediatric sickle cell disease (SCD) morbidity and mortality. There is a 50% risk for ACS recurrence after an initial episode, warranting primary and secondary preventive strategies. Early life exposures during critical periods of physiological development, including nutrition, may influence ACS development and recurrence. Through immunological and anti-inflammatory mechanisms, breastfeeding has been widely associated with reduced prevalence of respiratory illnesses among the general pediatric population but has not been explored among children with SCD.
Methods
A multivariable Poisson regression was employed to estimate adjusted prevalence ratios (aPRs) and confidence intervals (CIs) for recurrent ACS in the context of breastfeeding exposure, SCD genotype, SCD modifying therapy, age, sex, and asthma status among 67 children with SCD. Breastfeeding exposure was operationalized as total months of breastfeeding exposure and dichotomized to denote which subjects were vs. were not exposed to at least six months of exclusive breastfeeding, per World Health Organization recommendations. Collinearity diagnostics were assessed to ensure these two variables did not introduce significant multicollinearity.
Results
Subjects with exposure to at least six months of exclusive breastfeeding during infancy had a significantly lower prevalence of recurrent ACS compared to subjects that were not exclusively breastfed during the first six months of infancy (aPR = 0.44; 95% CI: 0.24-0.80; p = 0.008). Longer duration of breastfeeding, which included supplementation with infant formula, was associated with an increased prevalence of recurrent ACS (PR = 1.07 per month, 95% CI: 1.02-1.12; p = 0.003). In line with previous reports in the literature, a diagnosis of asthma was strongly associated with recurrent ACS (PR = 3.37, 95% CI: 1.48-7.65; p = 0.004), a more than three-fold increase in prevalence. Increasing age was modestly associated with a higher prevalence of recurrent ACS (PR = 1.07 per year, 95% CI: 1.01-1.13; p = 0.015). Severe genotype (Hgb SS/SB0) demonstrated a borderline associated with recurrent ACS prevalence (PR = 1.85, 95% CI: 0.98-3.51; p = 0.058). There were no associations detected between sex or disease-modifying therapy and recurrent ACS.
Conclusions
The findings from this observational study demonstrate an association between infant feeding practices and history of recurrent ACS among children with SCD. Specifically, six months or more of exclusive breastfeeding during infancy was notably associated with a lower prevalence of recurrent ACS, while a longer duration of overall breastfeeding, which included supplementation with infant formula, was modestly associated with a higher prevalence of recurrent ACS. The latter finding should be interpreted with caution, given the overall study design and absence of variables in our Poisson regression analysis modeled to account for the immunological, anti-inflammatory and antioxidant differences in human milk vs. infant formula. Confounding by indication may have also contributed to this finding if in fact subjects with higher susceptibility to respiratory illnesses were more strongly encouraged or inclined to breastfeed. Overall, this study justifies the need for future, larger prospective studies aimed to evaluate the potential role of infant feeding practices in ACS risk.