DAYLIGHT: Vitamin D Therapy in Individuals at High Risk of Hypertension (DAYLIGHT)
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ClinicalTrials.gov Identifier: NCT01240512 |
Recruitment Status
:
Completed
First Posted
: November 15, 2010
Last Update Posted
: March 9, 2017
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hypertension Vitamin D Deficiency Pre-Hypertension | Drug: Cholecalciferol | Not Applicable |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 534 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Triple (Participant, Care Provider, Investigator) |
Primary Purpose: | Treatment |
Official Title: | Daylight: The Effect of Vitamin D Supplementation on Blood Pressure in Vitamin D Deficient Individuals With Pre-Hypertension |
Study Start Date : | December 2010 |
Actual Primary Completion Date : | October 2013 |
Actual Study Completion Date : | October 2013 |

Arm | Intervention/treatment |
---|---|
Active Comparator: High Dose Arm
4000 IU/day Vitamin D3 (cholecalciferol) supplementation
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Drug: Cholecalciferol
Vitamin D3 (cholecalciferol) 200 IU and 2000 IU drops will be supplied by D Drops. It is supplied as a liquid containing 400 drops/bottle with a potency of 200 IU/drop or 2000 IU/drop. The contents of the label will be in accordance with all applicable regulatory requirements. The droppers are gravity-metered to deliver a consistent drop size (dosage). Two drops (either 200 IU or 2000 IU) of Vitamin D (cholecalciferol) is to be taken orally once-daily.
Other Name: Vitamin D3
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Active Comparator: Low Dose Arm
400 IU/day Vitamin D3 (cholecalciferol) supplementation
|
Drug: Cholecalciferol
Vitamin D3 (cholecalciferol) 200 IU and 2000 IU drops will be supplied by D Drops. It is supplied as a liquid containing 400 drops/bottle with a potency of 200 IU/drop or 2000 IU/drop. The contents of the label will be in accordance with all applicable regulatory requirements. The droppers are gravity-metered to deliver a consistent drop size (dosage). Two drops (either 200 IU or 2000 IU) of Vitamin D (cholecalciferol) is to be taken orally once-daily.
Other Name: Vitamin D3
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- The primary endpoint is defined as the change in mean 24-hour ambulatory systolic blood pressure. [ Time Frame: 24 hours ]
- Change in mean 24-hour ambulatory diastolic blood pressure [ Time Frame: 24 hours ]
- Change in mean daytime and nighttime ambulatory systolic and diastolic blood pressure [ Time Frame: 24 hours ]
- Change in mean clinic systolic and diastolic blood pressure [ Time Frame: 6 months ]
- Change in mean clinic pulse pressure [ Time Frame: 6 months ]
- Relation of vitamin D status to changes in clinic and 24-hour ambulatory blood pressure measurements [ Time Frame: 6 months ]

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Ages Eligible for Study: | 18 Years to 50 Years (Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01240512
United States, Connecticut | |
Hartford Hospital | |
Hartford, Connecticut, United States, 06106 | |
United States, Massachusetts | |
Massachusetts General Hospital | |
Boston, Massachusetts, United States, 02114 | |
United States, Minnesota | |
Abbott Northwestern Hospital | |
Minneapolis, Minnesota, United States, 55407 |
Principal Investigator: | Thomas J Wang, MD | Massachusetts General Hospital |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Thomas J. Wang, MD, Principal Investigator, Massachusetts General Hospital |
ClinicalTrials.gov Identifier: | NCT01240512 History of Changes |
Other Study ID Numbers: |
2010P001612 |
First Posted: | November 15, 2010 Key Record Dates |
Last Update Posted: | March 9, 2017 |
Last Verified: | March 2017 |
Additional relevant MeSH terms:
Hypertension Vitamin D Deficiency Prehypertension Vascular Diseases Cardiovascular Diseases Avitaminosis Deficiency Diseases Malnutrition Nutrition Disorders |
Vitamins Vitamin D Ergocalciferols Cholecalciferol Micronutrients Growth Substances Physiological Effects of Drugs Bone Density Conservation Agents |