This randomized controlled trial examined the impact of 25-hydroxy- vitamin D levels and high-dose vitamin D supplementation on isolated systolic hypertension. This was a parallel group, double-blind, placebo-controlled randomized trial. Primary care clinics and hospital clinics were utilized and participants were 70 years and older with systolic hypertension, as well as baseline 25-hydroxyvitamin D levels less than 30 ng/mL. The intervention was 100,000 U of oral cholecalciferol or matching placebo every 3 months for 1 year. The measurements included office blood pressure, arterial stiffness, endothelial function, cholesterol level, insulin resistance, and b-type natriuretic peptide level during 12 months. 159 participants were randomized. Mean baseline office systolic blood pressure was 163/78 mmHg. Mean baseline 25-hydroxyvitamin D level was 18 ng/mL. 25-hydroxyvitamin D levels increased in the treatment group compared with the placebo group. No significant treatment effect was seen for mean office blood pressure. No significant treatment effect was evident for any secondary outcome, including arterial stiffness, cholesterol levels, and others. There was no excess of adverse events in the treatment group and the total number of falls was non-significantly lower in the group receiving vitamin D. JAMA Intern Med. 2013 August. PMID: 23939263
