Gestational vitamin D and offspring risk of multiple sclerosis: a systematic review and meta-analysis.Ann Epidemiol. 2020 03; 43:11-17.AE
Our objective was to systematically review and meta-analyze studies that assessed the association between gestational vitamin D levels and risk of multiple sclerosis (MS) in offspring.
Embase and Pubmed databases were searched from inception to May 2018. Original, observational studies that investigated both clinically defined MS (in offspring) and vitamin D levels in utero or shortly after birth were included. Two reviewers independently abstracted data and assessed the quality of studies using the Newcastle-Ottawa Quality Assessment Scale. Summary effect estimates and 95% confidence intervals were calculated with random effects models using inverse variance weighting. Determinants of heterogeneity were evaluated.
Four case-control studies of moderate to low risk of bias were included. Summary effect estimates of the effect of higher levels of gestational vitamin D on risk of offspring MS demonstrated a significant protective effect in random effects (OR: 0.63, 95% CI: 0.47, 0.84) models and in a stratified analysis based on study quality. Factors identified as determinants of heterogeneity were the definitions of vitamin D deficiency, the characteristics of study participants, and the quality of the study.
Sufficient levels of vitamin D during pregnancy may be protective against offspring's development of multiple sclerosis later in life.