Vitamin D Supplementation and Cardiovascular Disease Risk

Abstract

Many studies,1,2 but not all, have shown that low bone density is associated with increased cardiovascular disease (CVD) risk. Vitamin D deficiency is common in the elderly and is associated with osteoporosis; however, the association of endogenous 25-OH vitamin D (25-OH D) levels with CVD events is controversial.3,4 CVD rates are higher during winter seasons and at increased geographic latitudes where average serum vitamin D levels are lowest.5 Low 25-OH D levels have been found in stroke6 and heart failure patients.7 Moreover, 25-OH D deficiency is associated with hypertension, obesity,8 glucose intolerance,8 and the metabolic syndrome,9 which may be responsible, at least in part, for its association with increased CVD risk. Article p 846 Although vitamin D supplementation improves bone strength, elevated serum vitamin D levels may be associated with lower levels of vascular calcification. In subjects at moderately high risk for coronary heart disease, endogenous serum vitamin D levels were inversely correlated with the extent of coronary artery calcification as determined by cardiac computed tomography.10 Vitamin D also has intriguing antiinflammatory properties11 that have potential therapeutic benefit in several autoimmune diseases and allograft rejection. In 2 small clinical trials,12,13 vitamin D supplementation lowered C-reactive protein levels. Additionally, 1,25(OH)2D induces relaxation of vascular smooth muscle cells …