Vitamin D Research Study - 1St Luke's Episcopal Hospital, Center for Orthopaedic Research and Education, Orthopaedic Nurse Researcher, Houston, TX 77025, USA. PURPOSE: To heighten awareness of the problems related to the high prevalence of suboptimal vitamin D status in hospitalized patients and the general population, including an overview of vitamin D biology, how vitamin D status is defined, the negative health issues associated with suboptimal vitamin D status, indications for treatment, treatment strategies, and controversies in the field. DATA SOURCES: (a) Literature review was performed using PubMed and CINAHL databases to locate and review medical, nursing, and nutritional journals. (b) Authors' recent prospective studies of 100 patients in a general tertiary hospital rehabilitation unit and 51 nonhospitalized volunteers. CONCLUSION: Poor vitamin D status (ranging from suboptimal to overt deficiency) is common in both hospitalized patients and ostensibly healthy individuals of all ages and geographic latitude. Suboptimal vitamin D status is associated with muscle weakness, functional deficits, and perhaps longer length of stay of hospitalized patients. Predictors of vitamin D status include race, poor nutrition, advanced age, use of multivitamins, ultraviolet light exposure, and grip strength. Fortunately, treatment with 50,000 IU of vitamin D(2) for several weeks is a very inexpensive and safe yet effective treatment to replete vitamin D status. IMPLICATIONS FOR PRACTICE: NPs should be aware of the indications for monitoring vitamin D status and the appropriate treatment for suboptimal vitamin D status. Improving vitamin D status may improve a patient's functional ability, therefore decreasing falls and preventing fractures, decreasing length of stay in the hospital, and decreasing the cost of health care. Providers can potentially improve the life of older adults by educating patients on the importance of vitamin D supplementation. PMID: 18042130 [PubMed - indexed for MEDLINE] Vitamin D Research Study - 2Bischoff-Ferrari HA, Shao A, Dawson-Hughes B, Hathcock J, Giovannucci E, Willett WC. Centre on Aging and Mobility, Department of Rheumatology and Institute of Physical Medicine, University Hospital Zurich, Gloriastrasse 25, 8091, Zurich, Switzerland, Heike.Bischoff@usz.ch. Current intake recommendations of 200 to 600 IU vitamin D per day may be insufficient for important disease outcomes reduced by vitamin D. INTRODUCTION: This study assessed the benefit of higher-dose and higher achieved 25-hydroxyvitamin D levels [25(OH)D] versus any associated risk. METHODS AND RESULTS: Based on double-blind randomized control trials (RCTs), eight for falls (n = 2426) and 12 for non-vertebral fractures (n = 42,279), there was a significant dose-response relationship between higher-dose and higher achieved 25(OH)D and greater fall and fracture prevention. Optimal benefits were observed at the highest dose tested to date for 700 to 1000 IU vitamin D per day or mean 25(OH)D between 75 and 110 nmol/l (30-44 ng/ml). Prospective cohort data on cardiovascular health and colorectal cancer prevention suggested increased benefits with the highest categories of 25(OH)D evaluated (median between 75 and 110 nmol/l). In 25 RCTs, mean serum calcium levels were not related to oral vitamin D up to 100,000 IU per day or achieved 25(OH)D up to 643 nmol/l. Mean levels of 75 to 110 nmol/l were reached in most RCTs with 1,800 to 4,000 IU vitamin D per day without risk. CONCLUSION: Our analysis suggests that mean serum 25(OH)D levels of about 75 to 110 nmol/l provide optimal benefits for all investigated endpoints without increasing health risks. These levels can be best obtained with oral doses in the range of 1,800 to 4,000 IU vitamin D per day; further work is needed, including subject and environment factors, to better define the doses that will achieve optimal blood levels in the large majority of the population. PMID: 19957164 [PubMed - as supplied by publisher] Vitamin D Research Study - 3Osteoporos Int. 2009 Dec 4. [Epub ahead of print]The efficacy of calcitriol therapy in the management of bone loss and fractures: a qualitative review. Peppone LJ, Hebl S, Purnell JQ, Reid ME, Rosier RN, Mustian KM, Palesh OG, Huston AJ, Ling MN, Morrow GR. Department of Radiation Oncology, University of Rochester, Rochester, NY, USA, luke_peppone@urmc.rochester.edu. Osteoporosis, a skeletal disorder characterized by a reduction in bone strength, increases fracture risk. Primary osteoporosis is usually a result of reduced bone mineral density as a consequence of natural aging. Secondary osteoporosis is usually a result of a disease, such as cystic fibrosis, or medical treatment, such as corticosteroids or cancer treatment. INTRODUCTION: Currently, ten million Americans are osteoporotic and an additional 34 million have the precursor condition, osteopenia. Osteoporosis leads to 1.5 million fractures and 500,000 hospitalizations annually. Osteoporosis-related fractures increase mortality and reduce quality of life. Calcitriol, the active form of vitamin D, regulates intestinal calcium absorption, among other actions. During the past four decades, many clinical trials investigating the effect of calcitriol on bone loss have been performed. METHODS: We conducted a systematic qualitative review of clinical trials that assessed calcitriol for the treatment of osteoporosis and bone loss. In these clinical trials, calcitriol was used as a monotherapy and in combination with other therapeutic bone agents. RESULTS AND CONCLUSION: Studies using calcitriol monotherapy, although not conclusive, found that calcitriol slowed the rate of bone loss in a variety of populations. Calcitriol in combination with other therapeutic bone agents was shown to have additional bone-preserving effects when compared to the use of therapeutic bone agents alone. A common side-effect of calcitriol therapy was hypercalcemia and hypercalciuria, but the degree of hypercalcemia was mild. Recent research found that intermittent dosing can reduce hypercalcemia rates. Calcitriol, alone or in combination with other agents, should be considered for the therapy of osteoporosis. PMID: 19960185 [PubMed - as supplied by publisher] Vitamin D Research Study - 4Gastroenterology. 2009 Nov;137(5 Suppl):S79-91.Vitamin D and the parenteral nutrition patient. DeLuca HF. Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706-1544, USA. deluca@biochem.wisc.edu Vitamin D is a prohormone produced in the skin epidermis when irradiated with sunlight or ultraviolet light B. It is also absorbed from food or supplements. Vitamin D must be converted to 25-hydroxyvitamin D3 (circulating form) and finally to the hormone, 1a,25-dihydroxyvitamin D3, before it can function. This hormone acts through a single nuclear receptor. The details of these conversions and molecular biology of the action of vitamin D3 are summarized. The physiologic functions of vitamin D have been expanded beyond the mineralization of the skeleton to include modulation of the immune system, terminal differentiation in several tissues, suppression of malignant cells, and anabolic activity in the skeleton and in the renal-cardiovascular system. Epidemiologic studies have associated vitamin D deficiency with an increased risk of colorectal and breast cancers and an increased risk of autoimmune diseases, such as multiple sclerosis, type 1 diabetes, and cardiovascular events. Thus, vitamin D is essential not only for the skeleton but also many other organ systems. Recommendations for 25-hydroxyvitamin D3 levels for PN patients are presented. PMID: 19874954 [PubMed - in process]
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