Burden of prematurity-associated recurrent wheezing: caregiver missed work in the D-Wheeze trial.

OBJECTIVE: This study describes the burden of prematurity-associated wheezing in black infants with respect to caregiver missed work. STUDY DESIGN: We analyzed data from the D-Wheeze trial (ClinicalTrials.gov identifier NCT01601847). Black infants between 28-0/7 to 36-6/7 weeks' gestational age at birth receiving <28 days of supplemental oxygen were enrolled. The primary outcome was missed work to care for the infant in the first year. RESULTS: 147/277 (53.1%) infants had caregivers who reported time off. In an adjusted model, vitamin D supplementation (OR 0.52 [95% CI 0.30-0.89]; P = 0.018), recurrent wheeze (OR 2.26 [95% CI, 1.15-4.44]; P = 0.018), and other children in the household <5 years old (OR 0.45 [95% CI 0.26-0.78]; P = 0.004) were significantly associated with caregiver missed work. CONCLUSIONS: Black premature infants had a significant burden of caregiver missed work, emphasizing the impact of prematurity-associated wheezing.

Effect of Vitamin D Supplementation on Recurrent Wheezing in Black Infants Who Were Born Preterm: The D-Wheeze Randomized Clinical Trial.

Importance: Black infants born preterm face high rates of recurrent wheezing throughout infancy. Vitamin D supplementation has the potential to positively or negatively affect wheezing through modulation of the pulmonary and immune systems. Objective: To assess the effectiveness of 2 vitamin D dosing strategies in preventing recurrent wheezing. Design, Setting, and Participants: A randomized clinical trial enrolled 300 black infants born at 28 to 36 weeks' gestation between January 2013 and January 2016 at 4 sites in the United States, and followed them up through March 2017. Randomization was stratified by site and maternal milk exposure. Interventions: Patients were enrolled prior to discharge from the neonatal intensive care unit or newborn nursery and received open-label multivitamin until they were consuming 200 IU/d of cholecalciferol from formula or fortifier added to human milk, after which they received either 400 IU/d of cholecalciferol until 6 months of age adjusted for prematurity (sustained supplementation) or placebo (diet-limited supplementation). One-hundred fifty three infants were randomized to the sustained group, and 147 were randomized to the diet-limited group. Main Outcomes and Measures: Recurrent wheezing by 12 months' adjusted age was the primary outcome. Results: Among 300 patients who were randomized (mean gestational age, 33 weeks; median birth weight, 1.9 kg), 277 (92.3%) completed the trial. Recurrent wheezing was experienced by 31.1% of infants in the sustained supplementation group and 41.8% of infants in the diet-limited supplementation group (difference, -10.7% [95% CI, -27.4% to -2.9%]; relative risk, 0.66 [95% CI, 0.47 to 0.94]). Upper and lower respiratory tract infections were among the most commonly reported adverse events. Upper respiratory infections were experienced by 84 of 153 infants (54.9%) in the sustained group and 83 of 147 infants (56.5%) in the diet-limited group (difference, -1.6% [95% CI, -17.1% to 7.0%]). Lower respiratory infections were experienced by 33 of 153 infants (21.6%) in the sustained group and 37 of 147 infants (25.2%) in the diet-limited group (difference, -3.6% [95% CI, -16.4% to 4.4%]). Conclusions and Relevance: Among black infants born preterm, sustained supplementation with vitamin D, compared with diet-limited supplementation, resulted in a reduced risk of recurrent wheezing by 12 months' adjusted age. Future research is needed to better understand the mechanisms and longer-term effects of vitamin D supplementation on wheezing in children born preterm. Trial Registration: ClinicalTrials.gov Identifier: NCT01601847.