Prevalence and risk factors of hypovitaminosis D among patients with diabetes mellitus from India: A systematic review and meta-analysis.

BACKGROUND

There is considerable evidence regarding the potential risk of hypovitaminosis D for various chronic conditions, including type 2 diabetes mellitus (T2DM). Although India essentially shares a tropical climate, it reports a high prevalence of vitamin D deficiency that is predominant in people with diabetes. This systematic review and meta-analysis were designed to look into the risk factors associated with hypovitaminosis D in diabetic patients from India and assess the prevalence.

METHODS

PubMed, Embase, and Cochrane Library were searched systematically for observational studies reporting the serum vitamin D levels of T2DM patients up to September 2024. A random effects model was employed to analyse the pooled prevalence of hypovitaminosis D and its risk factors.

RESULTS

Twelve studies of 8953 patients with diabetes (sample size) were included in the review. The combined prevalence of hypovitaminosis D was 79 % (95 % CI: 75 %-84 %, i2 = 97 %). Mean serum vitamin D level was 17.21 ng/mL (95 % CI: 16.87-17.56 ng/mL). More frequently noted risk factors included duration of diabetes, fatigue, body mass index, and HbA1c levels. However, the findings are limited by substantial heterogeneity, predominance of cross-sectional designs, and a paucity of high-quality, well-controlled studies from India.

CONCLUSION

Hypovitaminosis D is highly prevalent in Type 2 diabetes mellitus patients in India, with the level highly below optimum thresholds. Routine screening of vitamin D levels and targeted supplementation strategies may further improve metabolic control and reduce complications among this vulnerable population.