Jarrah Aldoseri

Background: The Middle East and North Africa (MENA) region faces a high cardiovascular disease (CVD) burden alongside endemic serum 25(OH)D (vitamin D) deficiency. This systematic review examines the relationship between vitamin D deficiency and CVD risk factors in MENA populations. Methods: PubMed, Cochrane Library, and Scopus were searched from inception to 18 October 2024, for observational studies in the MENA region examining vitamin D deficiency and cardiovascular risk factors in adults. Independent data extraction was conducted. Study quality was appraised using the Joanna Briggs Institute tool and the Newcastle–Ottawa Scale, with risk of bias visualized using Robvis. Weighted mean differences in cholesterol, body mass index (BMI), and HbA1c between those with and without vitamin D deficiency were computed with random-effects meta-analysis. The protocol was registered in PROSPERO (ID: CRD42025615188) and funded by the Royal College of Surgeons in Ireland—Medical University of Bahrain. Results: Seventeen studies from nine MENA countries were included, predominantly cross-sectional, involving community-based and disease-specific cohorts. Vitamin D deficiency was highly prevalent and consistently associated with higher adiposity and central obesity. Several studies reported significant links between deficiency and poor glycemic control, particularly in obese and prediabetic groups. Meta-analysis demonstrated significantly higher total cholesterol (MD = 0.32; 95% CI = 0.11 to 0.52, p < 0.001), BMI (MD = 1.81; 95% CI = 0.68 to 2.94, p < 0.001), and HbA1c levels (MD = 0.31; 95% CI = 0.06 to 0.57, p = 0.02) in vitamin D deficient individuals, with notable heterogeneity. Conclusions: Vitamin D deficiency is highly prevalent in the MENA region and consistently associated with adiposity-related risk factors. Despite heterogeneity, findings underscore the need for public health strategies and further research to clarify causal pathways and population-specific interventions.