View clinical trials related to Vitamin D Deficiency.
Filter by:Specific Aim 1: To compare effects of Vitamin D supplementation to usual care on symptoms in women transitioning to early postmenopause and determine the associated effect size in order to conduct a power analysis for a future RCT. Hypothesis: Vitamin D insufficient women in early postmenopause who are randomized to supplementation, titrated to achieve sufficiency for 2 months, will have fewer symptoms including hot flashes, mood, and musculoskeletal complaints than women randomized to usual care. Specific Aim 2: To compare effects of Vitamin D supplementation to usual care on body composition (by dual-energy x-ray absorptiometry [DXA] and by weight, BMI, waist to hip ratio) in overweight/obese women transitioning to early postmenopause and determine the associated effect size for a power analysis for a future RCT. Hypothesis: Vitamin D insufficient women in the menopausal transition randomized to supplementation, titrated to achieve sufficiency for 9 months, will improve DXA body composition (less total body and abdominal fat), compared to women in usual care, who will have increased body weight, including total and abdominal fat. Specific Aim 3: To estimate the proportion of overweight/obese middle-aged women who achieve sufficiency by 1 month versus 2 or more months and to determine if achieving sufficiency by 1 month varies by baseline characteristics. Hypothesis: About 80% of participants will achieve sufficient Vitamin D level by 1 month. Those who need more than 1 month for sufficiency will have lower baseline levels and higher initial BMI.
Study hypothesis: High-dose vitamin D leads to a shorter hospital stay in critically ill patients Vitamin D deficient patients will be randomized to receive either 540,000 IU cholecalciferol or placebo.
The purpose of this study is to determine the capability to absorb calcium as a measure of the sufficient levels of Vitamin D. Calcium absorption will be measured at baseline and after vitamin D3, by dual calcium isotope technique using stable isotopes in post menopausal women between the ages 50 and 70yrs. Subjects will have a screening visit, first and final visits. Subjects will be randomly assigned to a placebo or daily doses of vitamin D3. The specific aim of this study is to determine the level of vitamin D that will maximize the absorption of calcium and establish the relationship between the administered calcium dose and the actual absorbed calcium dose versus administered dose of Vitamin D and the serum levels of Vitamin D.
the study aims to messure the vitamin D levels in medical staff in the hospital. The physicians in the course of their internship who work indoors and work many night shifts have limited sun exposure in all seasons. Nursing staff who work shifts and work indoors are at the same risk of liltle sun exposure. The study addresses the amount of sun exposure, assessed by a sun exposure questioner, age, gender,work load related to number of shifts in the physicien group and in nursing group the job percentile we also adress religion (clothing cover)as a factor.
Background: Vitamin D is vital throughout pregnancy and lactation for both maternal and infant health. Health Canada recommends women take the AI of 5ug/day of vitamin D during pregnancy, however, it is unknown how much vitamin D is necessary to ensure both mother and baby reach a vitamin D serum concentration of 25OHD>75nmol/L.
Background: Vitamin D plays a key role in calcium absorption in the gut and in skeletal development. Vitamin D deficiency is common, affecting an estimated one billion people worldwide, including developed countries. Vitamin D deficiency causes rickets, the most common non-communicable disease of childhood. Rickets causes poor growth and skeletal deformities and, at its most severe, seizures and death. Recent data suggest that children with rickets have an increased risk for developing diabetes mellitus. Screening for vitamin D deficiency is not commonly done. It is generally diagnosed only after symptoms of rickets have developed. Prevention and treatment is simple and inexpensive. Hence, early detection of vitamin D deficiency through screening would be beneficial. Studies are urgently needed to validate such screening tests. Calcium balance is tightly regulated in the body and calcium loss in the urine (measured by the urine calcium-to-creatinine ratio) is a sensitive indicator of reduced calcium absorption, such as in vitamin D deficiency. Objective and Hypotheses. The objective of this study is to evaluate the urine calcium-to-creatinine ratio as a noninvasive and inexpensive screening test for vitamin D deficiency. Our hypotheses are 1) that the urine calcium-to-creatinine ratio correlates with blood vitamin D levels in infants and toddlers at risk for vitamin D deficiency and 2) that this test can be used to screen for vitamin D deficiency. Potential Impact. A validated screening tool would allow for the detection of vitamin D deficiency before the development of rickets, decreasing the morbidity and mortality of this common disease.
The purpose of this study is to evaluate how Vitamin D affects endothelial function, inflammation, lipids, insulin resistance, vitamin D levels, and PTH.
Study will look at baseline Vitamin D levels, calcium, albumin, liver enzymes, testosterone, osteocalcin, urine N telopeptides, bone mineral density, nutritional assessment and physical activity assessment of boys with hemophilia A or B (ages 2-20 yrs). Patients with low vitamin D levels will receive therapeutic doses of Vitamin D. At end of one year follow up studies will be repeated.
Hypothesis: Vitamin D supplementation lower renin-angiotensin system activity in obesity. Specific Aim: To investigate whether Vitamin D supplementation in obesity improves the vascular sensitivity to angiotensin II.
The purpose of this study is to determine if infrequent administration of oral vitamin D megadoses is effective treatment to maintain serum 25-hydroxyvitamin D(3) above target levels of 50-75 nmol/L. The investigators hypothesize that 100 000 IU or at least 200 000 IU vitamin D3 in every three months would be effective and safe treatment to achieve the target levels.