(P24-065-24) Prevalence and Correlates of Vitamin D in Young Children Living in Urban Slums of Mumbai: A Cross-Sectional Study

Objectives: In this cross-sectional study, we determined the prevalence of vitamin D deficiency and insufficiency and correlates of vitamin D status among children 12–18 months of age living in the urban slums of Mumbai, India at baseline, prior to a nutrition intervention.

Methods: Serum vitamin D (25[OH]D) concentrations were measured using chemiluminescence immunoassay in children with available sample volume (n=168) who participated in a randomized controlled feeding trial (NCT02233764). Vitamin D deficiency and insufficiency was defined according to the NASEM criteria as < 30 nmol/L and 30–49.9 nmol/L, respectively. Potential correlates were selected based on previous literature and biological plausibility, including 1) child characteristics e.g., amount of time of sun exposure, amount of skin exposed to the sun, age, sex, anthropometry; 2) maternal characteristics e.g., age, height, and education level; 3) socioeconomic status e.g., monthly income. Multivariate linear and binomial regressions were used to identify correlates associated with vitamin D status.

Results: The median (IQR) serum vitamin D concentration was 46.85 (31.98, 70.03) nmol/L. The prevalence of vitamin D deficiency was 18%, with an additional 38% of children being vitamin D insufficient. Serum retinol concentration, female sex, age at 1st measles-containing vaccine, anti-measles IgG titer and amount of skin exposed to the sun were positively associated with continuous serum vitamin D concentrations.

Conclusions: Nearly one in five children living in urban slums in Mumbai had vitamin D deficiency and were at an increased risk of developing rickets in the first two years of life in the population participating in this study.

Funding Sources: This project was funded by a HarvestPlus grant awarded to Cornell University.