21 Clinical Trials for Various Conditions
This study looks at the effects of calcium supplementation on bone density in women in their third decade of life. We placed women aged 19-27 who take in low amounts of calcium in their diets in one of two groups. We will give women in one group a placebo (inactive pill) and women in the other group 1500 milligrams of calcium per day (as calcium carbonate). We will monitor the results by looking at the change in bone mineral density measured at the hip, total body, forearm, and spine. Treatment will last 3 years.
The purpose of this study is to determine whether eating Kellogg's Nutri-Grain cereal bars will increase calcium intake in healthy adult women.
This study is to determine the amount of vitamin D required for a very low birth weight infant to reach vitamin D sufficiency and achieve optimal calcium health and bone growth.
Calcium Release Deficiency Syndrome (CRDS) is a newly discovered genetic arrhythmia syndrome that confers a risk of life-threatening arrhythmias secondary to RYR2 loss-of-function. The International CRDS registry has been designed to facilitate large-scale evaluation of CRDS, including its phenotypic spectrum, approaches to risk stratification, and optimal treatment strategies.
Calcium Release Deficiency Syndrome (CRDS) is a novel inherited arrhythmia syndrome secondary to RyR2 loss-of-function that confers a risk of sudden cardiac death. Diagnosis of CRDS presently requires cellular-based in vitro confirmation that an RyR2 variant causes loss-of-function. We hypothesize that CRDS can be diagnosed clinically through evaluation of the repolarization response to brief tachycardia, mediated by cardiac pacing, and a subsequent pause.
Study Purpose and Objectives: This study will utilize calcium hydroxylapatite (CaHA) to treat recession and hypersensitivity of the gums. The objectives of the study are: 1. to study the quality and quantity of changes in attached gums resulting from Radiesse(+) injections in the gingival tissue; 2. to determine the efficacy of Radiesse(+) in the reduction of tooth hypersensitivy caused by exposed roots relating to gingival recession; 3. to determine the efficacy of Radiesse(+) in the treatment of mild and moderate gingival recession.
Adequate levels of vitamin D are essential for bone health at all ages but low levels of vitamin D may also negatively impact other aspects of health such as blood pressure. The investigators have previously shown that adults with African ancestry living near the equator have much higher levels of vitamin D and higher levels of blood pressure compared to adults with African ancestry living in the Chicago area. Multiple clinical trials have examined vitamin D supplementation for reducing blood pressure levels but very few studies have focused on adults with African ancestry and low vitamin D levels. In addition, most previous clinical trials have not addressed calcium intake. While vitamin D may modulate blood pressure via its actions on activation of the renin angiotensin aldosterone system, it is also possible that vitamin D mediates blood pressure via its effects on gastrointestinal calcium absorption. This pilot study is a one arm study, which will assess the safety and feasibility of supplementing 15 young adults with African ancestry and low vitamin D levels with 5,000 IU of Cholecalciferol (vitamin D3) combined with 1000 mg of elemental calcium daily for 3 months. Participants will be recruited from the Maywood Illinois and surrounding areas with flyers and brochures. The investigators will also contact previous participants of the Modeling the Epidemiologic Study/Vitamin D Ancillary Study by phone and letters. At baseline, all participants will have blood pressure measured and will provide a fasting serum specimen and a 24-hour urine collection. Calcium, parathyroid hormone level vitamin D will be measured in serum specimens and 24-hour urine calcium excretion will be measured. Repeat visits will be completed at 6 and 12 weeks of follow-up to again measure resting blood pressure and serum calcium and vitamin D levels. The overall goal is to collect pilot data to help design a larger trial of vitamin D and calcium supplementation for lowering blood pressure in young adults with African ancestry.
In order to make bone health a reality for older adults, we need to consider the prevalence of Vitamin D deficiency in relation to environment latitude as well as vitamin D supplementation. Darker skin pigmentation and aging are known factors influencing the body's ability to synthesis adequate amounts of Vitamin D. The aim of this project is to document vitamin D deficiency in elderly African American women living in a southern latitude.
The investigators aim to recruit 60 women who have agreed to participate in an existing randomized, double-blind, placebo-controlled trial (Treatment of Vitamin D Insufficiency, HSC 2009-0055). In this trial, the investigators propose to evaluate the associations between magnesium intake, magnesium stores, fractional magnesium absorption and calcium homeostasis. The investigators will stratify 60 subjects in the sub-study, ensuring that approximately 20 subjects are randomized into each treatment arm (placebo, low-dose and high-dose vitamin D). The investigators already assess calcium homeostasis throughout the study by measuring bone mineral density, fractional calcium absorption, serum and urine calcium levels, among other tests. In the sub-study of 60 women, the investigators will evaluate whether habitually higher magnesium intake increases or decreases fractional calcium absorption. The investigators will evaluate the interplay between magnesium stores, vitamin D levels and serum parathyroid hormone levels. The investigators will directly assess magnesium stores using serum magnesium and 24-hour urine magnesium levels, and will measure magnesium absorption using the dual stable isotope approach.
The assumption has been that 1,25(OH)2D is solely responsible for calcium absorption. That has been one of the presumed causes of hyperparathyroidism in chronic kidney disease (CKD) (low 1,25(OH)2D leads to decreased calcium absorption, which increases parathyroid hormone release in compensation). Replacing 1,25 D directly has been the goal with using 1,25D or its analogues in CKD. There is very little data concerning use of native vitamin D or 25(OH)D in CKD, although autocrine functions in extrarenal tissues would use 25(OH)D. The latest KDIGO guidelines do recognize the autocrine role of vitamin D, but have no data on outcomes or doses or optimal levels to guide them and so have made a blanket recommendation to treat 25D levels in CKD by general healthy population guidelines. 1. This project focuses on an outcome (calcium absorption) that may be impacted by optimizing 25D status in renal patients. The investigators will assume for this project that a level of 25D \> 32 ng/ml is optimal in CKD patients as in a healthy population. 2. A secondary outcome is to quantify calcium absorption in CKD patients with and without vitamin D repletion and to quantify systemic 1,25D levels. This may clarify the roles 25D and 1,25D play in calcium absorption.
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.
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.
This is an open label, single center, randomized, active comparator controlled study, comparing the effects of vitamin D replacement using oral ergocalciferol versus paricalcitol on parathyroid hormone (PTH) levels in patients with stage 3 and 4 CKD and vitamin D deficiency or insufficiency. The purpose of this study is to determine which of these two approaches is more successful.
The investigators hypothesize that a 3 month course of vitamin D supplementation to treat 25(OH)D deficiency in stone formers with high levels of 24-hour urinary calcium will not increase urinary calcium excretion by greater than 10%.
Vitamin D aids in the body's ability to absorb calcium, it is a vital component in bone formation and break down. Reduced levels of vitamin D can indicate a vitamin deficiency and may depress serum calcium levels. The following is a list of common causes of vitamin D deficiency: lack of dairy products, alcohol usage, elderly, lack of exposure to sunlight, individuals with reduced mobility, GI malabsorption problems, dark complexion, severe liver damage, and renal failure. Many of these factors can be found in individuals with spinal cord injury. SCI results in disuse bone loss after acute injury, which continues with duration of injury. The goal of this study is to determine the effects of vitamin D and calcium supplements on calcium metabolism and vitamin D deficiency in individuals undergoing functional electrical stimulation (FES) stand retraining (SRT).
The investigators conducted a prospective un-blinded pilot study of Vitamin D plus Calcium (Ca) supplementation in overweight (BMI \> 27) premenopausal women diagnosed with Polycystic Ovarian Syndrome (PCOS), as defined by the Rotterdam Criteria, 2003, and who were deficient in vitamin D as reflected by serum 25-hydroxy (25-OH) vitamin D (serum levels \< 20 ng/mL).
The purpose is to perform a one-year study designed to assess whether treatment of hypovitaminosis D increases intestinal absorption of calcium, subsequent retention of calcium within bone, decreases bone turnover, and favorably impacts upon skeletal muscle mass, functional status, measures of physical function and quality of life. I hypothesize that treatment of hypovitaminosis D results in improved intestinal calcium absorption, greater retention of calcium within the bone reservoir and improved physical function, quality of life and muscle mass.
The purpose of this study is to answer the following questions: Does vitamin D increase calcium absorption, bone mass and muscle mass and function in women past menopause who have mildly low vitamin D levels? Do these benefits require prescription-strength vitamin D, or is an over the counter vitamin D dose enough?
The purpose of this study is to determine if treatment with vitamin D3 of 10,000 International Units (IU) daily in vitamin D deficient patients for 6 months will improve B type natriuretic peptide (BNP), a marker of heart function, compared to placebo. The investigators also aim to determine if vitamin D helps cardiopulmonary function as evaluated by cardiopulmonary exercise test (CPX), laboratory values, strength, and quality of life in patients with stable congestive heart failure (Class II or III).
Patients with chronic kidney disease (CKD) have a higher mortality rate than the general population, with cardiovascular disease (CVD) accounting for approximately 50% of deaths. Vascular calcification is a common finding in patients with CKD. Furthermore, patients with CKD develop secondary hyperparathyroidism, partly because of a decrease of calcitriol synthesis on the kidney. Treatment of secondary hyperparathyroidism includes use of activated vitamin D including calcitriol and paricalcitol. Recent evidence in dialysis patients suggest an improved survival in patients using paricalcitol compared to calcitriol. Studies in uremic rats suggests that there are differential effects of calcitriol and paricalcitol in expression of markers of soft-tissue calcification independent of calcium-phosphorus product. Calcitriol increased calcification of vascular smooth muscle cells cultured in calcification media. There was also significant increase in pulse pressure in animals treated with calcitriol. The investigators hypothesize that these different forms of vitamin D may have differential effects in vascular calcification progression in CKD patients.
The purpose of this study is to examine the effects of several doses of vitamin D on hormones related to bone, calcium absorption, bone density and muscle strength.