Vitamin D and Vascular Disease: The Current and Future Status of Vitamin D Therapy in Hypertension and Kidney Disease
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Over the past decade, vitamin D has generated considerable interest as potentially having important effects on the vasculature and the kidney. Animal and human data indicate that vitamin D suppresses the activity of the renin-angiotensin system and improves endothelial function. Observational studies in humans suggest that low 25-hydroxyvitamin D (25[OH]D) levels are associated with a higher risk of hypertension. However, findings from randomized trials of vitamin D supplementation (with cholecalciferol or ergocalciferol) to lower blood pressure are inconsistent, possibly stemming from variability in study population, sample size, vitamin D dose, and duration. Supplementation with activated vitamin D (i.e., 1,25-dihydroxyvitamin D or analogues) in patients with chronic kidney disease reduces urine albumin excretion, an important biomarker for future decline in renal function. These studies are reviewed, with special emphasis on recent findings. Definitive studies are warranted to elucidate the effects of vitamin D supplementation on mechanisms of hypertension and kidney disease.
KeywordsVitamin D Vascular disease Hypertension Blood pressure Kidney disease Renoprotection Clinical trials Paricalcitol Renin-angiotensin system 25[OH]D
The authors are funded by National Institutes of Health grants F32HL104776 (AV), 5R01HL105440 (JF), and American Heart Association grant 2009A050171 (JF).
No potential conflicts of interest relevant to this article were reported.
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