Correlation of cardio-metabolic parameters with vitamin D status in healthy premenopausal women

Purpose Vitamin D has been associated with metabolic disorders and increasing risk of cardiovascular diseases, with conflicting results. Aim of our study was to evaluate the relationship, if any, between cardio-metabolic risk factors and serum 25(OH)D concentrations in healthy women in premenopausal age. Methods We enrolled 200 healthy women, aged 19-50 years (mean age +/- SD, 38 +/- 11 years). In each subject, we measured serum 25(OH)D in relation to metabolic biomarkers and cardiovascular parameters. Results A status of vitamin D deficiency was found in 48% of the study population, while 38% showed levels higher than 30 ng/ml. Fasting glucose and insulin levels were significantly higher in subjects with vitamin D deficiency/insufficiency (P = 0.034 and P = 0.049, respectively) as well as HOMA-IR (P = 0.05). HDL cholesterol was significantly lower (P = 0.024) and intima-media thickness (IMT) higher (P = 0.014) in the vitamin D deficient/insufficient subjects. Moreover, serum 25(OH)D levels inversely correlated with insulin levels (P = 0.0001) and intima-media thickness (P = 0.015), and directly with serum HDL cholesterol (P = 0.010). At univariate regression analysis, the parameters that were significantly associated with vitamin D levels were insulin (P = 0.050), HDL cholesterol (P = 0.016), and intima-media thickness (P = 0.015). At multivariate analysis adjusted for age and BMI, vitamin D was still significantly associated with HDL cholesterol and intima-media thickness. Conclusions A positive association between vitamin D and HDL cholesterol was found in healthy women without any evidence of metabolic disorders, with a significant inverse correlation between vitamin D and IMT. These results suggest a possible protective role of 25(OH)D in cardiovascular disorders.