daylight: vitamin d therapy in individuals at high risk of hypertension

Conditions: Hypertension; Vitamin D Deficiency; Pre-Hypertension

Summary: this is a randomized, double-blind, multicenter, 6-month follow-up trial of low (400 iu/day) versus high (4000 iu/day) dose vitamin d supplementation in individuals with pre- and early stage 1 hypertension and vitamin d deficiency. a total of 530 participants (265 participants per treatment arm) will be randomized between 3 sites. approximately 2,250 participants will be screened between the 3 sites. vital signs, 24-hour ambulatory blood pressure monitoring, clinical laboratory safety tests and adverse event assessments will be performed to evaluate the effectiveness of the two doses of vitamin d on blood pressure. blood samples will be stored for future biomarker assessments. the total duration of the study is anticipated to be 18 months, assuming a 12 month enrollment period.


Eligibility criteria:
inclusion criteria: * males or females 18 to 50 years of age * systolic blood pressure of 120 to 159 mmhg and diastolic blood pressure ≤99 mmhg * vitamin d deficiency, defined as 25-hydroxyvitamin d \<25 ng/ml * no use of any anti-hypertensive medication in last 3 months or anticipated or planned use in next 6 months * no use of vitamin d supplementation in last 3 months, defined as vitamin d found in a multivitamin or supplement totaling \>400 iu per day or anticipated or planned use in next 6 months exclusion criteria: * use of any anti-hypertensive medication in last 3 months or anticipated or planned use in next 6 months * use of vitamin d supplementation in last 3 months, defined as vitamin d found in a multivitamin or supplement totaling \>400 iu per day or anticipated or planned use in next 6 months * use of st. john's wart, rifampin, any treatment for hiv, orlistat, oral glucocorticoids, phenobarbital, phenytoin, mineral oil, or bile acid sequestrants in the last 3 months or anticipated or planned use in next 6 months * female who is pregnant, nursing, or of childbearing potential and planning or anticipating pregnancy in next 6 months * history of diabetes mellitus (including type 1, type 2 and diet controlled) * serum creatinine \>2.0 mg/dl or estimated glomerular filtration rate (gfr) \<30 ml/min * calcium \>10.0 mg/dl or phosphorus \>5 mg/dl * history of kidney stones * body mass index \>38 kg/m2 * known cardiovascular disease: defined as prior myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass or stroke * history of cirrhosis or severe liver disease (defined as history of gi bleeding from liver disease, jaundice or ascites) * current heavy alcohol use: defined as drinking 5 or more drinks per occasion on 5 or more days in the past 30 days * history of ulcerative colitis, crohn's disease, celiac disease, colostomy, pancreatic enzyme deficiency, short bowel syndrome, gastric bypass, cystic fibrosis, or dumping syndrome. * allergy to coconut * regular use or planned use of artificial tanning lights in next 6 months * use of any investigational product or device in last 3 months or planned use in next 6 months * any condition which could limit the ability to complete and comply with 6-month follow up * unwillingness or inability to comply with study requirements * inability to provide informed consent