Clinical Research Directory

Role of Vitamin D Supplementation in Children With Irritable Bowel Syndrome

This study was designed to determine whether vitamin D supplementation improved symptoms in children with irritable bowel syndrome, a condition associated with repeated abdominal pain and changes in bowel habits. It was hypothesized that vitamin D supplementation would reduce symptom severity and increase blood vitamin D levels compared with placebo. The study was a randomized, placebo-controlled trial at the Department of Pediatrics, Aziz Bhatti Shaheed Teaching Hospital, Gujrat, Pakistan. It included 60 children aged 6-14 years who met established diagnostic criteria for irritable bowel syndrome and had low blood vitamin D levels of 10-29 ng/mL. Children were randomly assigned to two groups of 30 participants each. One group received oral vitamin D3 drops containing 2,000 international units once daily for 12 weeks. The other group received matching placebo drops without vitamin D for the same period. Both groups received routine supportive care, including advice on hydration, regular meals, diet, and symptom management. Follow-up visits were scheduled at 4, 8, and 12 weeks to assess symptoms, treatment adherence, and possible side effects. The main outcome was the change in symptom severity from the start of treatment to 12 weeks, measured using a standardized symptom score. The secondary outcome was the change in blood vitamin D levels over the same period. Changes in both outcomes were compared between the two groups.

Dietary Challenges in the Population of Nursing Homes' Residents

To obtain up-to-date data on nutritional status of older adults, a national dietary survey will be conducted in 2022/2023, providing data on the consumption of foods and enabling the assessment intakes of energy and specific nutrients. Participating subjects will be also screened for micronutrient status using blood biomarkers (focusing into vitamin D, folic acid, vitamin B12, and iron).

Vitamin D and Polycystic Ovarian Syndrome (PCOS)

Primary Objectives: To evaluate the efficacy of metformin and Vitamin D supplementation on serum insulin and serum androgen levels (Total testosterone, Steroid Hormone Binding Globulin, Free Androgen Index) levels compared metformin alone in infertile Poly cystic ovarian females of reproductive age group. Secondary Objectives: To measure change in endometrial thickness/number of follicles and follicular size by day 12 trans-vaginal ultrasound in the intervention group i.e. combination of metformin and vitamin D supplementation

Preeclampsia Research on Vitamin D, Inflammation, & Depression

This study is designed to comprehensively investigate the anti-inflammatory role of vitamin D in reproductive aged women, and its association with preeclampsia and depression. Findings will have substantial impact providing new information implicated in the development of preeclampsia (a condition that may include hypertension, tissue swelling caused by excessive fluid, and kidney stress) and postpartum depression (after birth). Additionally, the study is designed to understand how early mental health screening and evaluation can help pregnant women reduce their risk of developing postpartum depression. Testing the acceptability and effectiveness of this mental health screening, education and referral program at Cedars-Sinai Medical Center will provide valuable patient centered qualitative and quantitative data that can be used in future services planning. The study will enroll up to 200 pregnant women (in third trimester of pregnancy) in total.

Effect of Vitamin D Deficiency on the Frequency and Severity of Spinal Anesthesia-Induced Hypotension in Pregnant Women Undergoing Cesarean Section

Spinal anesthesia-induced hypotension remains a common and significant complication during cesarean sections, posing risks for both mother and fetus. Vitamin D deficiency, frequently observed in pregnant women, is associated with altered vascular function and potential hemodynamic instability. This prospective observational study aims to investigate whether vitamin D deficiency is associated with an increased incidence and severity of spinal anesthesia-induced hypotension in pregnant women undergoing elective cesarean delivery. Vitamin D levels will be measured preoperatively, and intraoperative hemodynamic parameters will be closely monitored. The findings could contribute to improved management strategies for pregnant patients at risk of severe hypotension.

The VITDALIZE Study: Effect of High-dose Vitamin D3 on 28-day Mortality in Adult Critically Ill Patients

In the VITdAL-ICU trial using a large oral dose of vitamin D3 in 480 adult critically ill patients, there was no benefit regarding the primary endpoint hospital length of stay. However, the predefined subgroup with severe vitamin D deficiency (25(OH)D ≤ 12ng/ml) had significantly lower 28-day mortality (36.3% placebo vs. 20.4% vitamin D group, hazard ratio (HR) 0.52 (0.30-0.89), number needed to treat = 6). Therefore, high-dose vitamin D3 in a population of severely vitamin D deficient critically ill patients is a promising and inexpensive intervention that requires confirmatory multicenter studies. To date, only 7 interventions (e.g. noninvasive ventilation or prone positioning) have ever demonstrated mortality benefit for Intensive Care Unit (ICU) patients in multicenter trials. In case of benefit, vitamin D treatment in critically ill patients could be immediately implemented worldwide.

Vitamin D Status and Its Influencing Factors in Zhejiang Province: A Multicenter Cross-Sectional Study

Vitamin D deficiency is a global public health problem, with an estimated 1 billion people affected worldwide, and large-scale systematic data for Zhejiang Province remain scarce. This is a multicenter, retrospective cross-sectional study. The objectives are to: (1) assess the distribution of serum 25-hydroxyvitamin D \[25(OH)D\] levels across regions, seasons, and demographic groups in Zhejiang Province and estimate the prevalence of vitamin D deficiency (\<20 ng/mL) and insufficiency (20-29 ng/mL); (2) identify and quantify key determinants of vitamin D status, including environmental exposures (ultraviolet radiation, green coverage), lifestyle (outdoor activity, sun protection), dietary vitamin D intake, and individual characteristics; and (3) provide scientific evidence for targeted intervention strategies, public health policy, and clinical guidelines in Zhejiang Province.

Bone Myoregulation Reflex and Postural Control in Vitamin D Deficiency

This observational study aims to investigate the relationship between vitamin D deficiency, postural stability, and neuromuscular control mechanisms in adults. The study will compare individuals with vitamin D deficiency and healthy controls. Participants will undergo a single-session evaluation including surface electromyography and postural stability assessments during standing tasks under different loading and vibration conditions. No invasive procedures, medications, or blood sampling will be performed. Previously obtained routine laboratory results will be used for vitamin D status. The study is designed to improve understanding of neuromuscular responses associated with vitamin D deficiency and to contribute to future rehabilitation strategies.

Effects of Vitamin D on Health Promotion During Pregnancy and Its Impact on Prematurity-Related Outcome

The VitDTracking study focuses on the relevance of maternal vitamin D levels and their association with prematurity, aiming to improve maternal and child health outcomes, particularly by reducing avoidable preterm births. In Portugal, vitamin D levels during pregnancy have never been studied. Epidemiological data from other countries reveal a high prevalence of vitamin D deficiency/insufficiency, especially in pregnant women. The hypovitaminoses prevalence remains high even with a supplementation dosage of 400 to 600 IU/day during pregnancy (dosage used in Portugal), which is considered as a suboptimal dose. This phenomenon is associated with adverse maternal and child outcomes, such as intrauterine growth restriction, preeclampsia, cholestasis, hypertension, and gestational diabetes as major causes of prematurity. Additionally, the Portuguese population has a higher prevalence of genome alterations that confer a lower capacity to produce vitamin D from sunlight exposure. These genetic characteristics are present in about 19% of the population, representing a prevalence four times higher than the European average (19% versus 4.75%), leading to a higher predisposition to vitamin D deficiency.

Preoperative Correction of Vitamin D Deficiency in Total Joint Arthroplasty (TJA)

The purpose of this study is being conducted to determine whether correcting low levels of vitamin D with a single high-dose supplement reduces complications after the participant's primary TJA.

Local and Systemic Inflammatory Bone Alterations Related to Dental Implant Survival.

Introduction: Dental implants offer a durable, aesthetic, and functional option for tooth replacement. However, they are not immune to failure. Current literature has highlighted the importance of systemic factors (such as vitamin D deficiency, osteoporosis and hypercolesterolemia) and local factors (such as the presence of nearby periapical infections or implant placement in sites with a history of endodontic failure) that affect bone health. Hypothesis: Bone alterations-whether systemic or local-represent a risk factor for implant failure and peri-implantitis. Objectives: To analyze implant failure and marginal bone loss in patients with local and/or systemic bone alterations compared to patients without such conditions. Methods: Implant failures occurring in patients treated within the Master's Program in Oral Medicine, Surgery, and Implantology at the University of Barcelona (MCIO-UB) over the last 10 years will be analyzed and correlated with bone factors (local and systemic) recorded in their medical histories. Cases lacking the radiographic and clinical data necessary to conduct the study will be excluded. Population: A total of 3,500 implants have been placed, with failure rates ranging from 4% to 8% depending on the techniques used; consequently, the study sample will consist of 192 implants. Cohorts of successful implants will be established by matching patients of the same sex and within a ±5-year age range who did not experience implant failure.

Impact of Vitamin D Supplementation on the Rate of Pathologic Complete Response in Vitamin D Deficient Patients

A two arm pilot study investigating the rate of pathologic complete response in patients with vitamin D deficiency and triple negative breast cancer undergoing standard neoadjuvant chemotherapy + vitamin D supplementation, including an observational arm to describe response in patients who are not deficient. Investigators hypothesize that vitamin D supplementation during neoadjuvant chemotherapy in operable triple negative breast cancer patients with vitamin D deficiency will increase the rate of pathologic complete response chain reaction to that of vitamin D sufficient patients based on historical controls.

Vitamin D Status in Obstructive Sleep Apnea With and Without Comorbidities

This retrospective observational study evaluates the relationship between vitamin D status and obstructive sleep apnea (OSA) in adults. The study includes 269 participants divided into four groups: healthy controls, participants with simple snoring without OSA, patients with OSA without comorbidities, and patients with OSA with comorbidities. The main objective is to compare serum 25-hydroxyvitamin D \[25(OH)D\] levels among these groups and to examine whether vitamin D status is associated with the presence and severity of OSA. Demographic characteristics, body mass index, laboratory measurements, and available overnight polysomnography findings are evaluated using existing medical records. The study also examines the distribution of vitamin D deficiency across the study groups and the relationship between vitamin D categories and OSA severity.

Vitamin A Supplementation in Allogeneic Stem Cell Transplantation.

The investigators hypothesize that single oral high dose supplementation with vitamin A will reduce the incidence of moderate-severe chronic graft-versus-host disease (GVHD) compared with placebo.

Evaluation of the Clinical and Psychological Impact of Vitamin D Replacement in Adolescent Females at Risk for Polycystic Ovarian Syndrome (PCOS)

This study is a double blind, placebo controlled, randomized trial of study subjects with PCOS and low vitamin D to 2 groups- placebo and vitamin D replacement. Participants and investigators will be blinded to treatment modality until the end of the trial period

Vitamin D2 vs Vitamin D2 Plus Calcitriol in Cholestatic Children With Vitamin D Deficiency

The goal of this clinical trial is to learn whether adding calcitriol to vitamin D2 can improve vitamin D deficiency in children with cholestasis and chronic liver disease. Cholestasis is a condition in which bile flow is reduced, which can make it difficult for the body to absorb and process vitamin D. The study will also learn about the safety of using vitamin D2 together with calcitriol. The main questions it aims to answer are: * Does vitamin D2 plus calcitriol increase blood 25-hydroxyvitamin D (25-OHD) levels more than vitamin D2 alone after 3 months of treatment? * Does vitamin D2 plus calcitriol help more children reach an adequate vitamin D level by 3 and 6 months? * What medical problems, especially high calcium or high phosphorus levels, occur during treatment? Researchers will compare children who receive vitamin D2 alone with children who receive vitamin D2 plus calcitriol to see which treatment improves vitamin D levels more effectively and safely. Participants will: * Take vitamin D2 alone or vitamin D2 plus calcitriol as assigned by randomization * Visit the clinic for study assessments at the start of the study, at 3 months, and at 6 months * Have blood tests to measure vitamin D levels, calcium, phosphorus, parathyroid hormone, liver function, and other safety markers * Have their treatment reviewed at 3 months; participants whose vitamin D level remains low may have their treatment adjusted according to the study plan * Bring back medication packages so researchers can check how regularly the study medicines were taken

Vitamin D Status and Asthma Control, Pulmonary Function, and Oxidative Stress in Adults With Bronchial Asthma

Asthma is a chronic inflammatory airway disease associated with variable airflow limitation and persistent respiratory symptoms. Vitamin D has been proposed as a potential biomarker related to immune regulation, asthma control, pulmonary function, and oxidative stress balance. This prospective cross-sectional observational study aims to investigate the association between serum 25-hydroxyvitamin D \[25(OH)D\] concentrations, asthma control, pulmonary function parameters, and erythrocyte oxidative stress biomarkers among Egyptian adults with bronchial asthma. A total of 200 adult asthma patients will be recruited from Abbassia Chest Hospital, Cairo, Egypt. Participants will undergo clinical assessment, Asthma Control Test (ACT), post-bronchodilator spirometry, serum vitamin D measurement, and oxidative stress biomarker assessment including malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), and reduced glutathione (GSH). Participants will be categorized according to serum 25(OH)D concentrations into vitamin D deficient, insufficient, and sufficient groups. No intervention or treatment assignment will be performed. 5\. Detailed Description

Vitamin D Status and Lipid Profile in Obese Adults With Type 2 Diabetes

This prospective, single-center, cross-sectional observational study aims to evaluate the association between serum 25-hydroxyvitamin D concentrations and lipid profile parameters among adults with obesity and established type 2 diabetes mellitus. A total of 160 participants will be recruited from an outpatient diabetes clinic in Cairo, Egypt. Each participant will undergo a single clinical, anthropometric, and laboratory assessment. No intervention or treatment will be assigned by the investigators.

Effect of Systemic Vitamin D on Dental Implant Osseointegration

The primary goal for any oral implantologist is to obtain satisfactory healing and long-term treatment success. Osseointegration is the key to dental implant success8 and is required to achieve direct structural and functional connection between living bone and the surface of a load-bearing artificial implant, is critical for the long-term success of dental implants. Successful dental implant therapy relies on achieving proper osseointegration, which ensures a stable structural and functional bond between the implant surface and surrounding bone. Although dental implants show a high overall success rate of around 95%.

Randomized Trial of Enteral Vitamin D Supplementation in Infants < 28 Weeks Gestational Age or <1000 Grams Birth Weight

The objective of the study is to compare supplementation with vitamin D at 800 IU/day to usual care for the first 28 days after birth with respect to 25 (OH) vitamin D levels and indicators of likely or plausible effects of vitamin D supplementation on the function or structure of the lung, bones, immune system, and brain in extremely premature (EP) infants who are \<28 weeks gestational age (GA) or \<1000 grams of birth weight (BW). The study results will be analyzed as intention to treat Bayesian analyses (Frequentist analyses will also be performed).

ViDES Trial (Vitamin D Extra Supplementation)

The objective of the study is to compare supplementation with vitamin D at 800 IU/day to usual care for the first 28 days after birth with respect to 25 (OH) vitamin D levels and indicators of likely or plausible effects of vitamin D supplementation on the function or structure of the lung, bones, immune system, and brain in extremely premature (EP) infants who are \<28 weeks gestational age (GA) or \<1000 grams of birth weight (BW). The study results will be analyzed as intention to treat Bayesian analyses (Frequentist analyses will also be performed).

The Effect of Vitamin D Supplementation on the Anti-inflammatory Response in Periodontal Diseases

A review of the literature revealed that while there are studies investigating the relationship between vitamin D and periodontal disease, there are no studies investigating the anti-inflammatory effect of vitamin D on periodontal disease. Investigators hypothesized that the increased incidence of periodontal disease in individuals with vitamin D deficiency might be due not only to pro-inflammatory effects but also to impaired bone metabolism and a decrease in the anti- inflammatory mechanism. Investigators aimed to determine this by comparing serum and DOS levels of 1,25-dihydroxyvitamin D (1,25(OH)2D), 25-hydroxyvitamin D (25(OH)D3), Receptor activator nuclear kappa B ligand (RANKL), osteoprotegerin (OPG), Tumor Necrosis Factor Related Apoptosis induced Ligand (TRAIL), Developmental endothelial locus (Del)-1, Lipoxin, Resolvin, interleukin (IL)-10, and transforming growth factor-β (TGF-β). The study will include 120 individuals who are systemically healthy based on clinical and radiographic examinations and diagnosed with Stage I-II periodontitis, Stage III-IV periodontitis, chronic gingivitis, and periodontally healthy. Periodontal clinical parameters (Probing pocket depth (PPD), Clinical attachment level (CAL), Bleeding on probing (BOP), Plaque index (PI), Gingival index (GI)) will be recorded three times: before treatment, and 6 and 12 weeks after treatment. Gingival crevicular fluid (GCF) and serum samples will be collected from participants at baseline and 12 weeks later for biochemical analysis.

Collegiate Athlete Study

The purpose of this study is to determine what percentage of Black collegiate athletes have low energy availability. It will also determine the percentage of Black collegiate athletes who have iron deficiency, suboptimal or low Vitamin D levels, and may be at risk for male and female athlete triad. Subsequent to the initial assessment, participants will complete a 12-week iron and vitamin D dietary supplementation protocol according to their baseline iron and vitamin D status.

Clinical Comparative Evaluation of the Use of Photodynamic Therapy in Conjunction With the Use of Vitamin D in Management Stage II Grade B Periodontitis Patients

Clinical Comparative Evaluation of the use of Photodynamic Therapy in conjunction with the use of Vitamin D in management Stage II Grade B Periodontitis Patients: A Randomized controlled clinical trial.