Serum 25-hydroxyvitamin D is independently associated with high-density lipoprotein cholesterol and the metabolic syndrome in men and women

BACKGROUND: Low vitamin D status has been associated with markers of cardiovascular disease risk. OBJECTIVE: This cross-sectional study assessed the relationships between serum 25-hydroxyvitamin D [25(OH)D] and selected markers for cardiovascular disease risk, including metabolic syndrome and its components, in adult men and women. METHODS: Fasting blood samples, anthropometric measurements, and blood pressure were assessed in 257 men and women. Dietary intake was assessed with food frequency and dietary supplement questionnaires. RESULTS: Total vitamin D intake and that from dietary supplements were significantly associated with increasing serum 25(OH)D tertile (both P < .001). Mean +/- SEM serum high-density lipoprotein cholesterol (HDL-C) increased in a graded fashion (P < .001) from the lowest (48.4 +/- 1.8 mg/dL) to the highest (62.3 +/- 2.1 mg/dL) 25(OH)D tertile. The relationship between 25(OH)D and HDL-C remained significant (P < .001) after adjustment for established determinants of the HDL-C, with each 10-ng/mL increase in 25(OH)D associated with a 4.2-mg/dL increase in HDL-C concentration. Serum triglycerides (P = .008), waist circumference (P < .001), and body mass index (P < .001) showed graded, inverse relationships with 25(OH)D tertile, and the prevalence of metabolic syndrome decreased significantly from the lowest to the highest 25(OH)D tertile (31%, 14%, and 10%, respectively, P for trend = .001). CONCLUSIONS: Lower serum 25(OH)D is associated with the metabolic syndrome and adverse values for some metabolic syndrome risk factors, particularly the HDL-C concentration. Research is warranted to assess whether increasing vitamin D intake will improve the metabolic cardiovascular risk factor profile. (C) 2009 National Lipid Association. All rights reserved.