729-P: Decreased Serum Vitamin D Level Implies Increased Cardiovascular Risk in Diabetes

Increase in homocysteine (HCY) level may increase cardiovascular risk (CVR), partly because of an impact on apolipoproteins and inflammation. Absorption of vitamin B12, involved in the regulation of HCY level, decreases with vitamin D deficiency. A possible association of vitamin D with visceral obesity and HCY was studied. HCY, 25-hydroxyvitamin D, vitamin B12, lipids, and other diabetes-related markers, including lipid accumulation product (LAP), were tested in 612 type 2 diabetic patients divided into four groups (1^st group: LAP ≤ Q1; 2^nd group: Q1 < LAP ≤ Med; 3^rd group: Med < LAP ≤ Q3, 4^th group: LAP ≥ Q3) according to LAP quartiles (Q1 = 28.5; Med = 50.59; Q3 = 80.64). LAP as an index, combining waist circumference and triglycerides, is related to risk of metabolic syndrome, diabetes and CVR. In all statistical tests: ANOVA, Tukey post-hoc test, and stepwise multivariate linear regression, α=0.05 was considered as statistically significant. Significant difference in vitamin D and B12, and high-density lipoprotein (HDL) according to LAP groups was determined. HDL differed significantly between the 1^st (1.56±0.27) and the 3^rd (1.24±0.17), and between the 1^st and the 4^th (1.19±0.25) group, vitamin D between the 1^st (67.21±11.87) and the 3^rd (60.34±10.78), and between the 1^st and the 4^th (51.29±13.41) group, and vitamin B12 differed significantly between the 1^st (319.33±158.71) and the 3^rd (212.14±71.92) group. After stepwise regression two best predictive variables for vitamin D were glomerular filtration rate (GFR) (parR²=0.12) and LAP (parR²=0.07), for vitamin B12 HCY (parR²=0.07) and age (parR²=0.07), and for HCY GFR (parR²=0.23) and vitamin B12 (parR²=0.09). Vitamins D and B12 differed according to quartiles of LAP, implying an influence of central obesity on their levels. LAP was one of the main predictors of vitamin D, and vitamin B12 was among the best predictive variables for HCY. The relationship between vitamin D, vitamin B12 and HCY implies involvement of decreased vitamin D in increased CVR.