Association of vitamin D status with metabolic syndrome and its components: A cross-sectional study in a population of high educated Iranian adults.

Aim: We aimed to assess the association of vitamin D status with metabolic syndrome and its components among high educated Iranian adults.

Method: In this cross-sectional study, 352 faculty members with age of 35 years or more, belong to Tarbiat Modares University, Tehran, Islamic Republic of Iran, were recruited during 2016 and 2017. Fasting blood samples were obtained to quantify serum 25(OH)D concentrations, glycemic indicators and lipid profile. Metabolic syndrome was defined based on the guidelines of the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Multivariate logistic regression adjusted for potential confounders was used to evaluate the association between vitamin D status and metabolic syndrome.

Result: Metabolic syndrome and vitamin D insufficiency were prevalent among 26% and 60.2% of subjects, respectively. There was no statistically significant difference in the prevalence of metabolic syndrome across quartiles of 25(OH)D levels either before or after adjusting for potential confounders (OR: 0.94, 95% CI: 0.43-1.95). In terms of metabolic syndrome components, subjects in the highest quartile of vitamin D levels had 59% decreased risk of abdominal obesity compared with those in the lowest quartile (OR: 0.41, 95% CI: 0.17-0.99), after adjusting for potential confounders. Such inverse relationship was also seen for elevated blood pressure (OR: 0.37, 95% CI: 0.14-0.99), and abnormal glucose homeostasis (OR: 0.40, 95% CI: 0.19-0.85).

Conclusion: Serum levels of 25(OH)D was inversely associated with the risk of abdominal obesity, hypertension, and abnormal glucose homeostasis. However, no significant relationship was seen for metabolic syndrome.