Vitamin D Therapy in Individuals With Prehypertension or Hypertension. Issue 3 (20th January 2015)

• Record Type: Journal Article
• Authors: Arora, Pankaj; Song, Yanna; Dusek, Jeffery; Plotnikoff, Gregory; Sabatine, Marc S.; Cheng, Susan; Valcour, Andre; Swales, Heather; Taylor, Beth; Carney, Erin; Guanaga, Derek; Young, Joseph R.; Karol, Courtney; Torre, Michael; Azzahir, Atum; Strachan, Semerit M.; O'Neill, Dillon C.; Wolf, Myles; Harrell, Frank; Newton-Cheh, Christopher; Wang, Thomas J.
• Is Part Of: Circulation. Volume 131:Issue 3(2015)
• Publication Date: 2015-01-20
• Subjects: Blood -- Circulation -- Periodicals; Cardiovascular system -- Periodicals; Cardiology -- Periodicals; Heart -- Diseases -- Periodicals; Blood Circulation; Cardiovascular System; Vascular Diseases; 616.1
• DOI: 10.1161/CIRCULATIONAHA.114.011732
• Languages: English
• ISSNs: 0009-7322

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title>Background—</title> <p>A large body of epidemiological and experimental evidence suggests that vitamin D deficiency may promote hypertension. This raises the possibility that vitamin D supplementation could be a simple intervention to reduce blood pressure, but data from prospective, randomized trials are limited.</p> </sec> <sec> <title>Methods and Results—</title> <p>A double-blind, randomized, controlled trial was conducted at 4 sites in the United States. We enrolled 534 individuals 18 to 50 years of age with low vitamin D status (25-hydroxyvitamin D levels ⩽25 ng/mL) and systolic blood pressure of 120 to 159 mm Hg. Participants were randomized to high-dose (4000 IU/d) versus low-dose (400 IU/d) oral vitamin D<sub>3</sub> for 6 months. The primary end point was change in mean 24-hour systolic blood pressure. Secondary end points included change in ambulatory diastolic blood pressure and clinic systolic and diastolic blood pressures. The median age was 38 years, and 62% of participants were men. Forty-six percent of participants were white, and 48% were black. The median 25-hydroxyvitamin D level at baseline was 15.3 ng/mL. Four-hundred fifty-five participants (85%) had at least 1 follow-up blood pressure measurement; 383 participants (72%) completed the full 6-month study. At the end of the study, there was no significant difference in the primary end point (change in mean 24-hour systolic blood pressure, −0.8 versus −1.6 mm Hg in the high-dose and low-dose arms; <italic>P</italic>=0.71) or in any of the secondary end points. Furthermore, there was no evidence of association between change in 25-hydroxyvitamin D and change in 24-hour systolic blood pressure at 6 months (Spearman correlation coefficient, −0.05, <italic>P</italic>=0.34). Results were consistent across prespecified subgroups.</p> </sec> <sec> <title>Conclusions—</title> <p>Vitamin D supplementation did not reduce blood pressure in individuals with prehypertension or stage I hypertension and vitamin D deficiency. Our findings suggest that the association between vitamin D status and elevated blood pressure noted in observational studies is not causal.</p> </sec> <sec> <title>Clinical Trial Registration—</title> <p>URL: <ext-link ext-link-type="uri" xlink:href="http://www.clinicaltrials.gov" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">http://www.clinicaltrials.gov</ext-link>. Unique identifier: NCT01240512.</p> </sec> </abstract>