High Blood Pressure — Effect of Vitamin D Supplementation on Blood Pressure in Elderly People
Citation(s)
Holick MF, Smith E, Pincus S Skin as the site of vitamin D synthesis and target tissue for 1,25-dihydroxyvitamin D3. Use of calcitriol (1,25-dihydroxyvitamin D3) for treatment of psoriasis. Arch Dermatol. 1987 Dec;123(12):1677-1683a. Review.
McDermott MM The international pandemic of chronic cardiovascular disease. JAMA. 2007 Mar 21;297(11):1253-5.
Yamshchikov AV, Desai NS, Blumberg HM, Ziegler TR, Tangpricha V Vitamin D for treatment and prevention of infectious diseases: a systematic review of randomized controlled trials. Endocr Pract. 2009 Jul-Aug;15(5):438-49. doi: 10.4158/EP09101.ORR. Review.
Effect of Vitamin D Supplementation on Blood Pressure in Elderly People
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
