Randomized controlled trials have suggested that vitamin D supplementation can prevent asthma and chronic obstructive pulmonary disease (COPD) exacerbations. For COPD, the benefit appears to be limited to individuals with baseline 25-hydroxyvitamin D (25OHD) levels <25 nmol/L. We performed a post hoc analysis of data from a randomized, double-blinded, placebo-controlled trial to investigate the effect that monthly, high-dose vitamin D supplementation (versus placebo) had on older adults with asthma and/or COPD.
View Article and Find Full Text PDFWith increasing numbers of randomized controlled trials (RCTs) investigating potential health events of vitamin D supplementation, a better understanding is required of the risk factors for adverse events and for study withdrawals. This analysis aimed to identify baseline risk factors of reporting an adverse event in a multi-year randomized double-blinded placebo-controlled trial of vitamin D supplementation. The secondary aim was to investigate if adverse events were associated with study withdrawals.
View Article and Find Full Text PDFBackground: Although adults with low vitamin D status are at increased risk of acute respiratory infection (ARI), randomized controlled trials of vitamin D supplementation have provided inconsistent results.
Methods: We performed a randomized, double-blinded, placebo-controlled trial of 5110 adults aged 50-84 years. In 2011-2012, participants were randomized to an initial oral dose of 200 000 IU vitamin D3 followed by 100 000 IU monthly (n = 2558) or placebo (n = 2552) until late 2013 (median follow-up, 1.
Background: A growing number of randomized controlled trials (RCTs) are investigating the potential health benefits of high-dose vitamin D supplementation. However, there are limited RCT data on the safety of calcium-related adverse effects.
Objective: We investigated the incidence of kidney stone and hypercalcemia events in a large, population-based RCT of vitamin D supplementation.
J Steroid Biochem Mol Biol
April 2019
In recent years, clinical trials increasingly have given large doses of vitamin D supplements to investigate possible health benefits beyond bone at high 25-hydroxyvitamin D levels. However, there are few publications on the safety of high-dose vitamin D given long term. The study objective was to investigate the cumulative relative risk (RR) of total adverse events, kidney stones, hypercalcemia and hypercalciuria from ≥2800 IU/d vitamin D or D supplementation, followed for one year or more in randomized controlled trials (RCTs).
View Article and Find Full Text PDFChronic pain is a major contributor to the global burden of disability. Prior studies on the association between serum 25-hydroxyvitamin D (25(OH)D) levels and chronic pain have yielded mixed results. The Vitamin D Assessment study, a large randomized controlled trial from New Zealand, offered the opportunity to examine this association in data collected at baseline in all participants, and among those with arthritis or depression.
View Article and Find Full Text PDFBackground: Previous studies, mostly with children, have reported inconsistent findings on the associations of vitamin D status with asthma prevalence, exacerbations, and control. Because of limited research with adults, we examined these associations in a large community-based sample of New Zealand adults.
Methods: 5110 participants, aged 50-84 years, were recruited from the community into a clinical trial of vitamin D supplementation.
Background: The use of high-dose vitamin D supplementation has increased in recent years. However, relatively little is known about the safety of long-term high doses.
Aims: To investigate the safety of a monthly high-dose of vitamin D supplementation taken for up to 4 years.
Importance: Previous randomized clinical trials have reported inconsistent results on the effect of vitamin D supplementation on cancer incidence.
Objective: To examine whether high-dose vitamin D supplementation received monthly, without calcium, is associated with a reduction in cancer incidence and cancer mortality in the general population.
Design, Setting, And Participants: This is a post hoc analysis of data from the Vitamin D Assessment (ViDA) study, a randomized, double-blind, placebo-controlled trial that recruited participants from family practices and community groups in Auckland, New Zealand, from April 5, 2011, through November 6, 2012, with follow-up completed December 31, 2015.
Observational studies suggest that vitamin D deficiency is associated with higher risk of pain. However, evidence on the effect of vitamin D supplementation on pain is limited and contradictory. The aim of this study was to compare the effect of monthly high-dose vitamin D supplementation on a pain impact questionnaire (PIQ-6) score and prescription of analgesics in the general population.
View Article and Find Full Text PDFAlthough observational studies suggest positive vitamin D-lung function associations, randomized trials are inconsistent. We examined effects of vitamin D supplementation on lung function. We recruited 442 adults (50-84 years, 58% male) into a randomized, double-blinded, placebo-controlled trial.
View Article and Find Full Text PDFBackground: Adults with low concentrations of 25-hydroxyvitamin D (25[OH]D) in blood have an increased risk of falls and fractures, but randomised trials of vitamin D supplementation have had inconsistent results. We aimed to assess the effect of high-dose vitamin D supplementation on fractures and falls.
Methods: The Vitamin D Assessment (ViDA) Study was a randomised, double-blind, placebo-controlled trial of healthy volunteers aged 50-84 years conducted at one centre in Auckland, New Zealand.
Importance: Cohort studies have reported increased incidence of cardiovascular disease (CVD) among individuals with low vitamin D status. To date, randomized clinical trials of vitamin D supplementation have not found an effect, possibly because of using too low a dose of vitamin D.
Objective: To examine whether monthly high-dose vitamin D supplementation prevents CVD in the general population.
Observational studies have shown that low vitamin D status is associated with an increased risk of cardiovascular disease, acute respiratory infection, falls and non-vertebral fractures. We recruited 5110 Auckland adults, aged 50-84 years, into a randomized, double-blind, placebo-controlled trial to test whether vitamin D supplementation protects against these four major outcomes. The intervention is a monthly cholecalciferol dose of 100,000IU (2.
View Article and Find Full Text PDFThis study sought to summarize the findings of the GBD 2010 (Global Burden of Diseases, Injuries, and Risk Factors) study for ischemic stroke (IS) and to report the impact of tobacco smoking on IS burden in specific countries. The GBD 2010 searched multiple databases to identify relevant studies published between 1990 and 2010. The GBD 2010 analytical tools were used to calculate region-specific IS incidence, mortality, mortality-to-incidence ratio, and disability-adjusted life years (DALY) lost, including 95% uncertainty intervals (UI).
View Article and Find Full Text PDFThis report summarizes the findings of the GBD 2010 (Global Burden of Diseases, Injuries, and Risk Factors) study for hemorrhagic stroke (HS). Multiple databases were searched for relevant studies published between 1990 and 2010. The GBD 2010 study provided standardized estimates of the incidence, mortality, mortality-to-incidence ratios (MIR), and disability-adjusted life years (DALY) lost for HS (including intracerebral hemorrhage and subarachnoid hemorrhage) by age, sex, and income level (high-income countries [HIC]; low- and middle-income countries [LMIC]) for 21 GBD 2010 regions in 1990, 2005, and 2010.
View Article and Find Full Text PDFBackground: Although stroke is the second leading cause of death worldwide, no comprehensive and comparable assessment of incidence, prevalence, mortality, disability, and epidemiological trends has been estimated for most regions. We used data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2010 (GBD 2010) to estimate the global and regional burden of stroke during 1990-2010.
Methods: We searched Medline, Embase, LILACS, Scopus, PubMed, Science Direct, Global Health Database, the WHO library, and WHO regional databases from 1990 to 2012 to identify relevant studies published between 1990 and 2010.
Background: The effects of systolic blood pressure (SBP), serum total cholesterol (TC), fasting plasma glucose (FPG), and body mass index (BMI) on the risk of cardiovascular diseases (CVD) have been established in epidemiological studies, but consistent estimates of effect sizes by age and sex are not available.
Methods: We reviewed large cohort pooling projects, evaluating effects of baseline or usual exposure to metabolic risks on ischemic heart disease (IHD), hypertensive heart disease (HHD), stroke, diabetes, and, as relevant selected other CVDs, after adjusting for important confounders. We pooled all data to estimate relative risks (RRs) for each risk factor and examined effect modification by age or other factors, using random effects models.
Aims: To assess whether statin use is associated with reduced mortality in patients with chronic obstructive pulmonary disease (COPD).
Methods: Hospitalisation, drug dispensing, and mortality records were linked for New Zealanders aged 50-80 years discharged from hospital with a first admission with COPD in 2006. Patients were classified according to whether or not they were prescribed statins prior to admission.
Background And Purpose: Although the neuropsychological literature typically examines stroke outcomes by hemisphere of lesion, the medical literature provides classifications more closely linked to circulatory distribution impacted by stroke. This article examined profiles of cognitive function by hemisphere and by Oxfordshire Community Stroke Project stroke classification.
Methods: This study included a sample of 315 5-year ischemic stroke survivors.
Objectives: Recent epidemiological studies have reported inverse associations between vitamin D status and blood pressure. The study aim is to determine if exposure to ultraviolet B radiation, which synthesizes vitamin D, lowers blood pressure, compared with ultraviolet A radiation.
Methods: Men and women (n = 119) with low vitamin D levels [serum 25-hydroxyvitamin D [25(OH)D] <50 nmol/l], completed a randomized clinical trial carried out during winter.