View clinical trials related to Vitamin D Deficiency.
Filter by:Vitamin D deficiency is a risk factor for mortality but existing data are limited by missing standardization of laboratory methods for 25-hydroxyvitamin D (25[OH]D). In a European consortium of eight cohort studies we use protocols of the Vitamin D Standardization Program (VDSP) to obtain standardized 25(OH)D data. Individual participant data (IPD) meta-analyses using a one step procedure will be performed to study associations of original and standardized 25(OH)D with all-cause, cardiovascular, and cancer mortality.
The optimal vitamin D replacement dose during pregnancy remains undefined. Therefore, the aim of this study is to test the hypothesis that a daily equivalent dose of vitamin D of 3,000 IU/day is needed for Middle Eastern women, to optimize maternal vitamin D level and neonatal musculoskeletal parameters, specifically knee-heel length at birth and bone mineral content at one month of age.
The purpose of this study is to examine the relationship between Vitamin D status and immunity.
The purpose of this study is to see whether giving a Vitamin D supplement to vitamin D deficient obese children and adolescents will decrease the risk of getting diabetes (Disease in which the person has high blood sugar). The number of vitamin D deficiency in U.S. children and teenagers has grown dramatically over the past 30 years. There are some reports suggesting that vitamin D supplementation in adults with pre diabetes (blood glucose higher than normal) and vitamin D treatment will prevent diabetes.
This trial objective is to assess whether doubling the daily intake of vitamin D improves serum vitamin D levels and serves as primary prevention of respiratory infections and asthma in premature infants. This is a prospective randomized (1:1) double-blinded trial. The study population will be randomized into two groups (1:1): - Intervention Group - 800 IU of Vitamin D once daily - Control Group - 400 IU of Vitamin D once daily Patients will be followed up for one year after randomization for serum Vitamin D levels and respiratory morbidity.
A double-blind randomized, placebo-controlled trial comparing the impact of 600 IU, 2000 IU, or 4000 IU of Vitamin D3 on third trimester 25(OH)D levels and change from baseline. The Vitamin D will be integrated in a standard prenatal vitamin, which will be taken from 12-16 weeks' gestation and continue throughout pregnancy. Umbilical cord 25(OH)D levels will also be determined. The investigators will generate preliminary data regarding Vitamin D intake and hypertensive disorders, blood pressure, and arterial function measured by tonography. The investigators will independently test blood pressure and proteinuria to identify preeclampsia cases.
The proposed study is a randomized, double-blind, controlled, multi-center clinical trial of six months of daily oral vitamin D3 (cholecalciferol). This study will randomize 334 community-dwelling post-menopausal women of European and African descent (~167 from each ancestry) in a 1:1 ratio between the control arm and the dosing algorithm arm using stratified block randomization with a block size of six and stratification by site (ancestry). The sample size of 334 includes 10% over-recruitment to allow for loss to follow-up. The European ancestry women will be seen in the Madison clinic and the African ancestry women will be seen in the Milwaukee clinic. The proposed study will focus on post-menopausal women because this is the subset of the population that both Dr. Engelman's and Dr. Binkley's preliminary data are drawn from. Moreover, 25(OH)D concentrations are typically lower in women and in older individuals, since production of vitamin D in the skin following sun exposure decreases with age. Therefore, this group of individuals is likely to benefit the most from vitamin D supplementation, especially when personalized based on biology using the proposed dosing algorithm.
This study investigates the effect of vitamin D deficiency on drug metabolism and transport in patients with chronic kidney disease (CKD) and in healthy controls. The central hypothesis is that vitamin D concentrations independently affect metabolism and transport function in CKD patients. An over-arching goal of this proposal is to make drug therapies safer and more effective to reduce the significant morbidity and mortality in patients with CKD.
In an ageing population, the need for interventions to help older people remain healthy, active and independent for as long as possible, increases. Although several studies suggest a beneficial effect of vitamin D3 on maintaining or improving muscle strength and physical functioning, particularly in vulnerable populations, results are contradicting. Randomized, placebo-controlled trials are needed to further establish the effect of vitamin D on muscle strength in the frail elderly population.The primary aim of this study is to determine the effect of daily supplementation with two different forms of vitamin D on muscle strength in frail elderly people over a period of 24 weeks.
Vitamin D deficiency is common worldwide, including in infants and children, and rickets remains a public health concern in many developing countries. The vitamin D status and prevalence of vitamin D deficiency in the Haitian population has not been studied. There is currently no approved point-of-care testing device for vitamin D deficiency. Iodine deficiency and resulting hypothyroidism is the leading cause of preventable neuro-developmental delay and cognitive impairment worldwide. Young infants and children are especially susceptible to sequelae of disruption in thyroid function given the dependence of the developing brain on sufficient levels of thyroid hormone. Perchlorate and thiocyanate have been described as potential environmental disrupters of thyroid function. Lead intoxication is a significant cause of disease throughout the world. Millions of people have suffered the effects of lead poisoning. Although most developed countries have taken drastic measures to limit the environmental lead levels, many countries in the developing world have not been able to address, or even assess, the problem. Our objectives are to study the following three components in 300 Haitian children between 9 months and 6 years of age in three different geographical areas of Haiti: 1) Vitamin D status and prevalence of rickets, environmental factors associated with low vitamin D levels, and the accuracy and efficacy of a vitamin D point-of-care testing (POCT) device for the screening of vitamin D insufficiency. 2) Iodine status and thyroid function, and environmental disruptors such as perchlorate and thiocyanate as potential risk factors for abnormal thyroid function. 3) Lead levels and the extent of childhood lead poisoning.