Search results for " umbrella"
showing 9 items of 29 documents
Metformin and health outcomes:An umbrella review of systematic reviews with meta-analyses
2021
Background:\ud \ud The objective was to capture the breadth of outcomes that have been associated with metformin use and to systematically assess the quality, strength and credibility of these associations using the umbrella review methodology.\ud \ud Methods:\ud \ud Four major databases were searched until 31 May 2020. Meta‐analyses of observational studies and meta‐analyses of randomized controlled trials (RCTs) (including active and placebo control arms) were included.\ud \ud Results:\ud \ud From 175 eligible publications, we identified 427 different meta‐analyses, including 167 meta‐analyses of observational studies, 147 meta‐analyses of RCTs for metformin vs placebo/no treatment and 11…
Consumption of Fish and ω-3 Fatty Acids and Cancer Risk: An Umbrella Review of Meta-Analyses of Observational Studies
2020
Multiple studies have suggested that ω-3 fatty acid intake may have a protective effect on cancer risk; however, its true association with cancer risk remains controversial. We performed an umbrella review of meta-analyses to summarize and evaluate the evidence for the association between ω-3 fatty acid intake and cancer outcomes. We searched PubMed, Embase, and the Cochrane Database of Systematic Reviews from inception to December 1, 2018. We included meta-analyses of observational studies that examined associations between intake of fish or ω-3 fatty acid and cancer risk (gastrointestinal, liver, breast, gynecologic, prostate, brain, lung, and skin) and determined the level of evidence of…
Human Immunodeficiency Virus Infection and Diverse Physical Health Outcomes: An Umbrella Review of Meta-analyses of Observational Studies.
2019
Abstract Background Our aim was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies and physical health outcomes associated with human immunodeficiency virus (HIV) but not acquired immunodeficiency syndrome. Methods We performed an umbrella review of observational studies. Evidence was graded as convincing, highly suggestive, suggestive, weak, or nonsignificant. Results From 3413 studies returned, 20 were included, covering 55 health outcomes. Median number of participants was 18 743 (range 403–225 000 000). Overall, 45 (81.8%) of the 55 unique outcomes reported nominally significant summary results (P < .05). O…
Tea Consumption and Risk of Cancer
2020
Tea is one of the most widely consumed beverages, but its association with cancer risk remains controversial and unclear. We performed an umbrella review to clarify and determine the associations between tea consumption and various types of cancer by summarizing and recalculating the existing meta-analyses. Meta-analyses of observational studies reporting associations between tea consumption and cancer risk were searched on PubMed and Embase. Associations found to be statistically significant were further classified into levels of evidence (convincing, suggestive, or weak), based on P value, between-study heterogeneity, prediction intervals, and small study effects. Sixty-four observational…
STEM CELLS FOR TREATMENT OF CARDIOVASCULAR DISEASES: AN UMBRELLA REVIEW OF RANDOMIZED CONTROLLED TRIALS
2021
AIMS:\ud \ud Stem cells are a promising therapy for various medical conditions. The literature regarding their adoption for the clinical care of cardiovascular diseases (CVD) is still conflicting. Therefore, our aim is to assess the strength and credibility of the evidence on clinical outcomes and application of stem cells derived from systematic reviews and meta-analyses of intervention studies in CVD.\ud \ud METHODS and RESULTS:\ud \ud Umbrella review of systematic reviews with meta-analyses of randomized controlled trials (RCTs) using placebo/no intervention as control group. For meta-analyses of RCTs, outcomes with a random-effect p-value< 0.05, the GRADE (Grading of Recommendations Ass…
Physical activity and exercise in mild cognitive impairment and dementia::an umbrella review of intervention and observational studies
2020
Objectives:\ud \ud The aim of this umbrella review was to determine the effect of physical activity/exercise on improving cognitive and noncognitive outcomes in people with MCI (mild cognitive impairment) and dementia.\ud \ud Design:\ud \ud Umbrella review of systematic reviews (SR), with or without meta-analyses (MAs), of randomized controlled trials (RCTs) and observational studies.\ud \ud Settings and Participants:\ud \ud People with MCI or dementia, confirmed through validated assessment measures. Any form of physical activity/exercise was included. As controls, we included participants not following any prespecified physical activity/exercise intervention or following the same standard…
Orthostatic hypotension and health outcomes: an umbrella review of observational studies
2019
To investigate potential relationships between orthostatic hypotension (OH) and negative health outcomes and mortality, through an umbrella review with integrated meta-analyses. Orthostatic hypotension is significantly associated with several negative outcomes in older people, but a suggestive evidence is available only for higher risk of coronary heart disease congestive heart failure, stroke, falls dementia, and all-cause mortality. Orthostatic hypotension seems to be significantly associated with several negative health outcomes in older people, even if only associations with coronary heart disease, congestive heart failure, stroke, falls, dementia, and all-cause mortality are supported …
Interventions for reducing loneliness: An umbrella review of intervention studies
2020
Loneliness is a common phenomenon associated with several negative health outcomes. Current knowledge regarding interventions for reducing loneliness in randomised controlled trials (RCTs) is conflicting. The aim of the present work is to provide an overview of interventions to reduce loneliness, using an umbrella review of previously published systematic reviews and meta-analyses. We searched major databases from database inception to 31 March 2020 for RCTs comparing active versus non-active interventions for reducing loneliness. For each intervention, random-effects summary effect size and 95% confidence intervals (CIs) were calculated. For significant outcomes (p-value < 0.05), the GR…
Effect of low-dose aspirin on health outcomes: An umbrella review of systematic reviews and meta-analyses.
2020
Aims:\ud \ud This study aimed to use an umbrella review methodology to capture the range of outcomes that were associated with low‐dose aspirin and to systematically assess the credibility of this evidence.\ud \ud Methods:\ud \ud Aspirin is associated with several health outcomes, but the overall benefit/risk balance related to aspirin use is unclear. We searched three major databases up to 15 August 2019 for meta‐analyses of observational studies and randomized controlled trials (RCTs) including low‐dose aspirin compared to placebo or other treatments. Based on random‐effects summary effect sizes, 95% prediction intervals, heterogeneity, small‐study effects and excess significance, signifi…