Vitamin D deficiency and post-stroke depression: A systematic review and meta-analysis

Objective: Low vitamin D levels have often been associated with depression as well as worsen stroke outcomes. With post-stroke depression (PSD) being an important factor contributing to poor recovery and rehabilitation and thereby poor functional outcomes, this study was undertaken to explore the role of vitamin D deficiency in PSD and their correlation with stroke prognosis and outcomes. Methods: A systematic search of eligible studies from PubMed, MEDLINE, Cochrane CENTRAL, and Google Scholar were identified. Selected studies were those that met the inclusion criteria. Statistical analysis was conducted using Review Manager 5.4.1. A random-effects model was used to pool the data when heterogeneity was seen and so, results were reported in the standard mean differences within their corresponding 95 % confidence interval. Results: Our analysis showed statistically significant clinical depression in the Vitamin D deficient group on the BDI-II (SMD = 6.90 [3.32, 10.48]; p = 0.0002) and PHQ-9 (SMD = 3.20 [1.84, 4.56]; p < 0.00001) scales. Of the seven studies, four showed significantly poorer prognosis in PSD patients with respect to NIHSS (SMD = 1.54; [0.34, 2.74]; p < 0.0001) and MMSE (SMD = -2.53 [3.79, 1.27]; p < 0.0001). Conclusion: This study shows a significant association between serum Vitamin D levels and PSD. Further studies are needed to explore causal relationships and the effect of vitamin supplementation on stroke prognosis and outcomes in relation to PSD