Active clinical trials for "Vitamin D Deficiency"

Polycystic Ovary Syndrome (PCOS) affects 5 to 10% of women of reproductive age. It is characterized by a cluster of hyperandrogenism, hyperinsulinemia, menstrual dysfunction, hirsutism and infertility. Although the pathogenesis of PCOS is unknown, accumulating evidence suggests that the dysregulation of some angiogenic factors, such as transforming growth factor-β (TGF-β) and vascular endothelial growth factor (VEGF), may be implicated. TGF-βs and VEGF exert a diverse range of biological functions regulating cell proliferation, angiogenesis, fibroblast activation and tissue fibrosis. PCOS ovaries show all the hallmarks of TGF-β and VEGF upregulation, including increased collagen deposition in ovarian stroma and theca, supported by increased vascularity. Consistent with this, The investigators recently showed that TGF-β1 is increased in serum of PCOS women while its circulating receptor soluble endoglin (sENG) is decreased, resulting in greater TGF-β1 bioavailability. Furthermore, it has been shown that women with PCOS have increased VEGF levels in the serum and/or follicular fluid. PCOS patients also have decreased vitamin D levels, and vitamin D treatment has been previously shown to improve various clinical parameters in PCOS women, including glucose intolerance, hypertension and androgen levels. Interestingly, vitamin D has been shown to decrease TGF-β1 and VEGF levels in several diseases, including myelofibrosis and various human cancer cells. Therefore, the investigators hypothesize that vitamin D treatment of PCOS women will result in a decrease of serum TGF-β1 levels and/or VEGF levels concomitant with improvement in clinical disease parameters. In addition, the investigators hypothesize that improvement in clinical disease parameters will correlate with changes in serum VEGF levels and TGF-β1 bioavailability. Our aim in the present study is to investigate the effects of vitamin D treatment on serum VEGF and TGF-β1/sENG levels in PCOS women, and assess whether changes in these angiogenic factors following vitamin D treatment correlate with clinical disease in these women. For this end, PCOS patients who are vitamin D-deficient will be treated with vitamin D and their serum levels of VEGF, TGF-β1 and its sENG receptor will be measured before and after treatment. In addition, clinical disease parameters will be recorded before and 4 months after treatment, including serum glucose and insulin levels, serum androgen levels, and blood pressure. The proposed study aims to identify a putative link between vitamin D, VEGF, and TGF-β1 in the context of PCOS, and provide a novel molecular explanation for the beneficial clinical effects of vitamin D on PCOS patients.

This is a pre-post open label trial to assess the change in Vitamin D blood levels following treatment with three doses of topical Vitamin D3 in subjects with existing Vitamin D deficiency.

Recently, a special emphasis has recently been directed to the potential role of vitamin D and some regulatory peptides (e.g. adipokines and follistatin) and their associated metabolic roles and genetic factors in the development of PCOS and its related co-morbidities. The aim of this study was to assess the feasibility of conducting a pragmatic RCT assessing the effectiveness of adopting a protocol of screening for and correcting Vitamin D deficiency in women with PCOS seeking fertility treatment in a low/middle income care (LMIC) setting

The trial plan to determine whether a daily capsule containing vitamin D(3) (2000 IU), calcium (600 mg), both, or a placebo for 6 months in UAE citizens with evidence of vitamin D deficiency will lead to a clinical benefit. The proposed study will also determine the threshold of vitamin D and calcium intake or levels considered optimal for UAE citizen's health

Urinary incontinence (UI) is a common disorder among older women that greatly affects quality of life. Emerging evidence from observational studies links vitamin D insufficiency with UI. Prior to a larger intervention trial of vitamin D among older women with low serum vitamin D levels and urgency UI, we propose a pilot study in 100 older women comparing weekly, oral vitamin D3 50,000 IU to placebo. We hypothesize that adequate vitamin D supplementation will improve UI symptoms in older women with vitamin D deficiency. Changes in UI-episodes will be assessed by a 7-day bladder diary and other validated symptom measures administered at baseline and after 12-weeks of intervention. Serum calcium and 25(OH)D levels will be monitored. The expected outcomes will provide new knowledge regarding the impact of vitamin D supplementation on UI symptom improvement and inform a larger, randomized controlled clinical trial involving vitamin D supplementation.

evaluated the effect and safety of a single high dose of cholecalciferol in Chinese young people.

Circa-annual variations in 25-hydroxyvitamin D [25(OH)D] levels have been well established, and there also seems to be an effect of season on bone turnover and bone mass. been shown that bone turnover follows a circa-annual rhythm. On the basis of human clinical results, it was suggested that adipose tissue functions as a vitamin D buffering system that to a certain extent prevents uncontrolled synthesis of 25(OH)D in the liver. Directly related to this issue is the question of how much vitamin D is needed to ensure target serum 25-hydroxyvitamin D [25(OH)D] concentrations. According to the recommended dietary allowances, persons should achieve "levels of intake of essential nutrients considered to be adequate to meet the known nutritional needs of practically all healthy persons" Moreover it is important to note that the significant percentage of the population is temporarily of continuously deficient in vitamin D. In the similar condition of vitamin D deficiency, the aetiology is very different since only as almost exclusively as a consequence of a primary disease in children it is manifested: hypovitaminosis D is highly prevalent among children on renal substitution therapy, regardless of the type of therapy used and the stage of renal failure. The rationale providing high dose strengths of vitamin D based on an assumption of better compliance especially in adult with senior age patients; also a potential for faster resolution of vitamin D deficiency, since utilization of cholecalciferol is higher when patients had low levels of 25(OH)D, and vice versa, there is a plateau phase when close to normal range (Vieth 2001). According to clinical data, a doses equivalent of daily 1000 IU, (7000 IU per week, or 30000 IU per month) is considered as a minimal effective dose to treat vitamin D deficiency. The treatment of vitamin D with a duration of 30 days may result and increase of 6-12.5 nmol/L. With the deficiency criteria considered as <20 ng/ml, the vitamin supplementation is indicative, the treatment dosages should be adjusted to the increase planned to achieve the mid-normal range. As the base of calculations, the doses of 40 IU results in an increase of 0.4 ng/ml in a period of 60 days. Accordingly 1000 IU in a period of 2-5 month resulted in an increase of approx 10 ng/ml. The risk of overdose in relatively low, since the absorption and the metabolic path is well controlled: automatic mechanisms downregulation at normal ranges. In this study the there are three groups in the similar daily dose equivalent of 1000 IU/day. The absorption of daily , weekly and monthly dosing should have a buffered effect due to the body adipose tissues, balancing the daily 1,25(OH)D levels, and moreover to provide a biological reservoir. The three doses are considered as comparable in efficacy and safety. The fourth group is intended to utilize the expanded dose range of 4286 IU/ day, using the 30.000 IU tablets on a weekly dosing schedule. This group is to demonstrate the efficacy of higher doses to normalize the vitamin D levels, within a reasonable timeframe of 60-90 days.

Vitamin D plays a critical role in maintaining bone health, as well as preventing cardiovascular disease, cancer, and various autoimmune diseases, such as diabetes. Vitamin D deficiency is very common in the United States and worldwide, and is now being increasingly recognized and treated. One group in which vitamin D deficiency may be particularly important is patients who have had kidney stones. These patients frequently have elevated levels of calcium in their urine, which is a common and important risk factor for calcium containing kidney stones. Because vitamin D increases absorption of calcium into the blood by the intestines, physicians may be reluctant to prescribe vitamin D therapy to patients with vitamin D deficiency if they also have kidney stones and high amounts of calcium in the urine. They are concerned about the possible risk of increasing the amount of calcium in the urine (and thereby increasing the risk of calcium stones occurring again). However, studies in patients without kidney stones, as well as studies in patients with high calcium levels in the urine, have demonstrated that giving vitamin D is effective and safe and does not increase calcium in the urine. Therefore, the investigators will study the effects of giving vitamin D on the amount of calcium in the urine in patients with a history of kidney stones and elevated calcium in the urine. The investigators will evaluate the safety of giving vitamin D to this particular group of patients.

The role of vitamin D in respiratory health remains uncertain. Whether vitamin D reduces clinically important exacerbations of childhood asthma remains uncertain. We compared rapid to maintenance vitamin D repletion analyzed by baseline vitamin D level.

As the use of bariatric surgery for treatment of extreme obesity adults continues to rise, clinicians must be aware of pre-existing nutritional deficiencies in overweight and obese patients. Nutritional deficiencies are common in patients undergoing bariatric surgery and these deficiencies should be detected and addressed early to avoid post-operative complications. To improve long-term outcomes following bariatric surgery, nutritional screening and prescribing appropriate supplementation to prevent nutrient deficiencies is needed. Vitamin D deficiency is common following bariatric surgery and has been reported to occur in 50-80% bariatric patients.The goal of this pilot study is to help develop nutrient supplementation interventions following two types of bariatric surgery: Roux-en Y gastric bypass and sleeve gastrectomy. Recently, several studies in adults have revealed an inverse relationship between body fat and blood 25-hydroxyvitamin D3 [25(OH)D] levels, the relevant marker of low vitamin D status. Although vitamin D is well known for its essential role in bone metabolism and calcium homeostasis, increasing evidence is linking vitamin D to obesity. This study will evaluate vitamin D status during post operative daily supplementation of 2,000 IU of vitamin D3 and 1500 mg of calcium through assessment of changes in serum 25(OH)D, parathyroid hormone (PTH), calcium and phosphorus at baseline, 4 weeks, and 12 weeks following surgery. The dietary contribution of vitamin D and calcium will be estimated by food records analyzed using the University of Minnesota 2010 Nutrition Data System for Research (NDSR) program. Primary Hypothesis: Daily supplementation with 2,000 IU of vitamin D3 for 12 weeks will significantly increase mean serum 25(OH)D levels in obese subjects following bariatric surgery compared to baseline levels. Secondary Hypothesis: The percent response above baseline to daily supplementation with 2,000 IU of vitamin D3 will significantly differ between Roux-en Y and sleeve gastrectomy patients.