Original article. Prevalence of vitamin D deficiency and association of serum vitamin D level with anthropometric and metabolic factors in metabolic syndrome patients

Background: Accumulating evidence suggests that vitamin D deficiency may contribute to an increased risk of glucose intolerance, diabetes, insulin resistance, and metabolic syndrome. Vitamin D levels vary between different populations and their association with metabolic syndrome in non-western populations remains equivocal.

Objective: We examined the prevalence of vitamin D deficiency and association of vitamin D levels with anthropometric and metabolic factors in metabolic syndrome patients.

Methods: A cross-sectional study was conducted in 300 patients with metabolic syndrome. Patients were prospectively recruited, physically examined, and assessed for vitamin D levels and other laboratory data.

Results: The prevalence of vitamin D deficiency [25(OH)D ≤20 ng/mL] was 40.7% [95% CI = 35% to 46%]. In multivariate analysis, after adjustment for all variables, we found that increased waist circumference (WC) (adjusted odds ratio [AOR] = 1.058; 95% CI = 1.016-1.103), decreased hand skin color darkness (AOR = 0.757; 95% CI = 0.597-0.959), increased total cholesterol (AOR = 1.019; 95% CI = 1.005-1.032), and increased systolic blood pressure (SBP) (AOR = 1.029; 95% CI = 1.003-1.055) were significantly associated with an increased risk of vitamin D deficiency.

Conclusion: High prevalence of vitamin D deficiency has been observed in metabolic syndrome patients. After multivariate adjustment for all variables, high WC, light skin color, high total cholesterol levels, and high SBP were significantly associated with an increased risk of vitamin D deficiency.