Vitamin D deficiency and respiratory morbidity among African American very low birth weight infants

Abstract

BackgroundVery low birth weight infants (VLBWI) have unexplained variation in respiratory morbidity, including respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD). We examined a potential association to serum 25-hydroxyvitamin D (s-25OHD) on day one. Study designProspective, observational study on 89 VLBWI (≤1250 g). S-25OHD (day one and 21) and respiratory severity score (RSS) (day one) were examined. Other respiratory morbidities including BPD were compared between infants with s-25OHD ≤ 10 ng/ml (deficient) versus >10 ng/ml (adequate). ResultsEighty one neonates (91%) were African Americans. The mean (SD) birthweight was 868 (229) g, gestational age 27 (2) weeks. On day one, mean (SD) s-25OHD was 15.48 (8.31) ng/ml, with 32 (37%) being vitamin D deficient. The deficiency and adequate VLBWI groups had similar birthweight; 860 (262) vs 873 (210) g, and gestational age; 27 (2) vs 27 (2) weeks. In 78 survivors, s-25OHD rose from 15.48 (8.31) ng/ml day one to 52.36 (22.49) ng/ml day 21 after supplementation, p < 0.001. On day one, increasing RSS was inversely related to s-25OHD, trend p = 0.054. Compared to the adequate group, the deficiency group had higher RSS (5.0 ± 2.7 vs 3.6 ± 1.9), required surfactant therapy more frequently (91% vs 72%), and needed home oxygen therapy more often (48% vs 26%), p ≤ 0.05 for all. Among infants with BPD, the severity of disease was inversely related to s-25OHD, trend p < 0.09. ConclusionLower levels of s-25OHD were associated with increased severity of RDS and BPD among a cohort of mostly African American VLBWI.