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Clinical Nutrition (Edinburgh, Scotland) Jun 2020Maternal vitamin D deficiency has been associated with an increased risk for preeclampsia. Despite this, the current evidence regarding the efficacy of vitamin D... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Maternal vitamin D deficiency has been associated with an increased risk for preeclampsia. Despite this, the current evidence regarding the efficacy of vitamin D supplementation in preventing preeclampsia is controversial. To assess the impact of vitamin D supplementation on the risk of preeclampsia, we performed a systematic review of the literature and a meta-analysis of the available randomized clinical trials (RCTs).
METHODS
The primary outcome was preeclampsia. Subgroup analyses were carried out considering the timing of the supplementation, type of intervention and the study design. Meta-regression analysis, including the amount of vitamin D and maternal age, were planned to explore heterogeneity (PROSPERO database registration number: CRD42019119207).
RESULTS
Data were pooled from 27 RCTs comprising 59 arms, which included overall 4777 participants, of whom 2487 were in the vitamin D-treated arm and 2290 in the control arm. Vitamin D administration in pregnancy was associated with a reduced risk of preeclampsia (odd ratio [OR] 0.37, 95% confidence interval [CI]: 0.26, 0.52; I = 0%). If the vitamin D supplementation was started up to 20 weeks' gestation, the odds was a little lower (OR 0.35, 95% CI: 0.24, 0.50, p < 0.001). The effect was largely independent of the supplementation cessation (until delivery or not), type of intervention (vitamin D alone or in association with calcium), and study design. Increasing dose of vitamin D was associated with reduced incidence of preeclampsia (slope of log OR: -1.1, 95% CI: -1.73, -0.46; p < 0.001).
CONCLUSIONS
Results suggest that vitamin D supplementation may be useful in preventing preeclampsia. These data are especially useful for health-care providers who engage in the management of pregnant women at risk for preeclampsia. Our findings are a call for action to definitively address vitamin D supplementation as a possible intervention strategy in preventing preeclampsia in pregnancy.
Topics: Adolescent; Adult; Avitaminosis; Dietary Supplements; Female; Humans; Incidence; Middle Aged; Pre-Eclampsia; Pregnancy; Protective Factors; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Treatment Outcome; Vitamin D; Young Adult
PubMed: 31526611
DOI: 10.1016/j.clnu.2019.08.015 -
Journal of the American Heart... Jun 2015Guidelines recommend exercise for cardiovascular health, although evidence from trials linking exercise to cardiovascular health through intermediate biomarkers remains... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Guidelines recommend exercise for cardiovascular health, although evidence from trials linking exercise to cardiovascular health through intermediate biomarkers remains inconsistent. We performed a meta-analysis of randomized controlled trials to quantify the impact of exercise on cardiorespiratory fitness and a variety of conventional and novel cardiometabolic biomarkers in adults without cardiovascular disease.
METHODS AND RESULTS
Two researchers selected 160 randomized controlled trials (7487 participants) based on literature searches of Medline, Embase, and Cochrane Central (January 1965 to March 2014). Data were extracted using a standardized protocol. A random-effects meta-analysis and systematic review was conducted to evaluate the effects of exercise interventions on cardiorespiratory fitness and circulating biomarkers. Exercise significantly raised absolute and relative cardiorespiratory fitness. Lipid profiles were improved in exercise groups, with lower levels of triglycerides and higher levels of high-density lipoprotein cholesterol and apolipoprotein A1. Lower levels of fasting insulin, homeostatic model assessment-insulin resistance, and glycosylated hemoglobin A1c were found in exercise groups. Compared with controls, exercise groups had higher levels of interleukin-18 and lower levels of leptin, fibrinogen, and angiotensin II. In addition, we found that the exercise effects were modified by age, sex, and health status such that people aged <50 years, men, and people with type 2 diabetes, hypertension, dyslipidemia, or metabolic syndrome appeared to benefit more.
CONCLUSIONS
This meta-analysis showed that exercise significantly improved cardiorespiratory fitness and some cardiometabolic biomarkers. The effects of exercise were modified by age, sex, and health status. Findings from this study have significant implications for future design of targeted lifestyle interventions.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Biomarkers; Cardiovascular Diseases; Exercise; Female; Health Status; Humans; Male; Middle Aged; Physical Fitness; Prognosis; Protective Factors; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Risk Reduction Behavior; Sex Factors; Young Adult
PubMed: 26116691
DOI: 10.1161/JAHA.115.002014 -
Gastroenterology Sep 2019Multiple environmental factors have been associated with the development of inflammatory bowel diseases (IBDs). We performed an umbrella review of meta-analyses to... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Multiple environmental factors have been associated with the development of inflammatory bowel diseases (IBDs). We performed an umbrella review of meta-analyses to summarize available epidemiologic evidence and assess its credibility.
METHODS
We systematically identified and appraised meta-analyses of observational studies examining environmental factors and risk of IBD (Crohn's disease [CD] or ulcerative colitis [UC]). For each meta-analysis, we considered the random effects estimate, its 95% confidence interval, the estimates of heterogeneity, and small-study effects, and we graded the evidence according to prespecified criteria. Methodologic quality was assessed with AMSTAR (ie, A Measurement Tool to Assess Systematic Reviews) 2.
RESULTS
We examined 183 estimates in 53 meta-analyses of 71 environmental factors related to lifestyles and hygiene, surgeries, drug exposures, diet, microorganisms, and vaccinations. We identified 9 factors that increase risk of IBD: smoking (CD), urban living (CD and IBD), appendectomy (CD), tonsillectomy (CD), antibiotic exposure (IBD), oral contraceptive use (IBD), consumption of soft drinks (UC), vitamin D deficiency (IBD), and non-Helicobacter pylori-like enterohepatic Helicobacter species (IBD). We identified 7 factors that reduce risk of IBD: physical activity (CD), breastfeeding (IBD), bed sharing (CD), tea consumption (UC), high levels of folate (IBD), high levels of vitamin D (CD), and H pylori infection (CD, UC, and IBD). Epidemiologic evidence for all of these associations was of high to moderate strength; we identified another 11 factors associated with increased risk and 16 factors associated with reduced risk with weak credibility. Methodologic quality varied considerably among meta-analyses. Several associations were based on findings from retrospective studies, so it is not possible to determine if these are effects of IBD or the results of recall bias.
CONCLUSIONS
In an umbrella review of meta-analyses, we found varying levels of evidence for associations of different environmental factors with risk of IBD. High-quality prospective studies with analyses of samples from patients with recent diagnoses of IBD are needed to determine whether these factors cause or are results of IBD and their pathogenic mechanisms.
Topics: Colitis, Ulcerative; Crohn Disease; Drug-Related Side Effects and Adverse Reactions; Environment; Environmental Exposure; Humans; Hygiene; Life Style; Protective Factors; Risk Assessment; Risk Factors; Surgical Procedures, Operative; Vaccination
PubMed: 31014995
DOI: 10.1053/j.gastro.2019.04.016 -
Gastroenterology Oct 2022Many studies have assessed risk factors of irritable bowel syndrome (IBS) and other abdominal pain-related disorders of gut-brain interaction (AP-DGBI); however, the... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Many studies have assessed risk factors of irritable bowel syndrome (IBS) and other abdominal pain-related disorders of gut-brain interaction (AP-DGBI); however, the role of these factors is unclear due to heterogeneous study designs. The aim of this systematic review was to extensively evaluate the literature and determine clinical risk and protective factors for the presence and persistence of AP-DGBI in children and adults.
METHODS
A PubMed search identified studies investigating potential risk and protective factors for AP-DGBI in adults and children. Inclusion criteria included fully published studies with a control group; exclusion criteria included poor-quality studies (using a validated scale). For each factor, the proportion of studies that found the factor to be a risk factor, protective factor, or neither was summarized. The number of studies, diagnostic criteria, number of subjects, and average study quality rating provided further context. Whenever possible, a meta-analysis generated pooled odds ratios or mean difference.
RESULTS
The systematic review included 348 studies. Female sex, gastroenteritis, abuse, stress, psychological disorders, somatic symptoms, and poor sleep were consistent risk factors for developing AP-DGBI in adults and children. In adults, additional risk factors included obesity, smoking, and increased use of medical resources. Protective AP-DGBI factors in adults included social support and optimism; no studies for protective factors were found for children.
CONCLUSIONS
There are multiple risk factors for AP-DGBI in adults and children. These include female sex, gastroenteritis, abuse, stress, poor sleep, obesity, psychological disorders, and somatic symptoms. Additional studies are needed in children, on protective factors, and on factors associated with persistence of AP-DGBI.
Topics: Abdominal Pain; Adult; Brain; Child; Female; Gastroenteritis; Gastrointestinal Diseases; Humans; Irritable Bowel Syndrome; Medically Unexplained Symptoms; Obesity; Risk Factors
PubMed: 35716771
DOI: 10.1053/j.gastro.2022.06.028 -
BMJ (Clinical Research Ed.) Oct 2021To examine the associations between dietary intake and tissue biomarkers of alpha linolenic acid (ALA) and risk of mortality from all causes, cardiovascular disease... (Meta-Analysis)
Meta-Analysis
Dietary intake and biomarkers of alpha linolenic acid and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of cohort studies.
OBJECTIVE
To examine the associations between dietary intake and tissue biomarkers of alpha linolenic acid (ALA) and risk of mortality from all causes, cardiovascular disease (CVD), and cancer.
DESIGN
Systematic review and meta-analysis of prospective cohort studies.
DATA SOURCES
PubMed, Scopus, ISI Web of Science, and Google Scholar to 30 April 2021.
STUDY SELECTION
Prospective cohort studies that reported the risk estimates for death from all causes, CVD, and cancer.
DATA SYNTHESIS
Summary relative risks and 95% confidence intervals were calculated for the highest versus lowest categories of ALA intake using random effects and fixed effects models. Linear and non-linear dose-response analyses were conducted to assess the dose-response associations between ALA intake and mortality.
RESULTS
41 articles from prospective cohort studies were included in this systematic review and meta-analysis, totalling 1 197 564 participants. During follow-up ranging from two to 32 years, 198 113 deaths from all causes, 62 773 from CVD, and 65 954 from cancer were recorded. High intake of ALA compared with low intake was significantly associated with a lower risk of deaths from all causes (pooled relative risk 0.90, 95% confidence interval 0.83 to 0.97, I=77.8%, 15 studies), CVD (0.92, 0.86 to 0.99, I=48.2%, n=16), and coronary heart disease (CHD) (0.89, 0.81 to 0.97, I=5.6%, n=9), and a slightly higher risk of cancer mortality (1.06, 1.02 to 1.11, I=3.8%, n=10). In the dose-response analysis, a 1 g/day increase in ALA intake (equivalent to one tablespoon of canola oil or 0.5 ounces of walnut) was associated with a 5% lower risk of all cause (0.95, 0.91 to 0.99, I=76.2%, n=12) and CVD mortality (0.95, 0.91 to 0.98, I=30.7%, n=14). The pooled relative risks for the highest compared with lowest tissue levels of ALA indicated a significant inverse association with all cause mortality (0.95, 0.90 to 0.99, I=8.2%, n=26). Also, based on the dose-response analysis, each 1 standard deviation increment in blood concentrations of ALA was associated with a lower risk of CHD mortality (0.92, 0.86 to 0.98, I=37.1%, n=14).
CONCLUSIONS
The findings show that dietary ALA intake is associated with a reduced risk of mortality from all causes, CVD, and CHD, and a slightly higher risk of cancer mortality, whereas higher blood levels of ALA are associated with a reduced risk of all cause and CHD mortality only.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO CRD42021229487.
Topics: Cardiovascular Diseases; Eating; Humans; Mortality; Neoplasms; Protective Factors; Risk Assessment; alpha-Linolenic Acid
PubMed: 34645650
DOI: 10.1136/bmj.n2213 -
Gastroenterology Apr 2021Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal cancer (CRC). We performed a systematic review and meta-analysis to identify all... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND AIMS
Patients with inflammatory bowel disease (IBD) have an increased risk of colorectal cancer (CRC). We performed a systematic review and meta-analysis to identify all prognostic factors for advanced colorectal neoplasia (aCRN, high-grade dysplasia, or CRC) in patients with IBD.
METHODS
A systematic literature search was conducted according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Risk of bias was assessed using the Quality in Prognostic Studies tool. Random-effects models were created separately for odds and hazard ratios, different study designs, and univariable or multivariable data. The evidence for all prognostic factors was categorized as "weak", "moderate", or "strong", based on estimate of effect sizes, heterogeneity, and risk of bias.
RESULTS
A total of 164 studies were included, allowing pooled analysis of 31 potential prognostic factors. In the univariable analysis, the evidence for extensive disease was classified as strong while evidence for low-grade dysplasia, strictures, primary sclerosing cholangitis, post-inflammatory polyps, family history of CRC, and ulcerative colitis versus Crohn's disease was considered moderate. Evidence for any dysplasia, colon segment resection, aneuploidy, male sex, and age was classified as weak. In addition, histologic inflammation was identified as a risk factor in multivariable analysis (weak evidence). The evidence for the protective factors colonoscopic surveillance, 5-Aminosalicylic Acid, thiopurines, and smoking was moderate in univariable analysis. Multivariable analysis provided weak evidence for statin use.
CONCLUSIONS
In this systematic review and meta-analysis, we identified 13 risk factors and 5 protective factors for aCRN in IBD patients, based on univariable and/or multivariable pooled analyses. These findings might lay the groundwork for an improved CRC risk stratification-based surveillance in IBD.
Topics: Colitis, Ulcerative; Colitis-Associated Neoplasms; Colorectal Neoplasms; Crohn Disease; Humans; Neoplasm Grading; Prognosis; Protective Factors; Risk Assessment; Risk Factors
PubMed: 33385426
DOI: 10.1053/j.gastro.2020.12.036 -
Clinical Reviews in Allergy & Immunology Oct 2023Many potential environmental risk factors, protective factors, and biomarkers of AR have been published, but so far, the strength and consistency of their evidence are... (Review)
Review
Many potential environmental risk factors, protective factors, and biomarkers of AR have been published, but so far, the strength and consistency of their evidence are unclear. We conducted a comprehensive review of environmental risk, protective factors, and biomarkers for AR to establish the evidence hierarchy. We systematically searched Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to December 31, 2022. We calculated summary effect estimate (odds ratio (OR), relative risk (RR), hazard ratio (HR), and standardized mean difference (SMD)), 95% confidence interval, random effects p value, I statistic, 95% prediction interval, small study effects, and excess significance biases, and stratification of the level of evidence. Methodological quality was assessed by AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). We retrieved 4478 articles, of which 43 met the inclusion criteria. The 43 eligible articles identified 31 potential environmental risk factors (10,806,206 total population, two study not reported), 11 potential environmental protective factors (823,883 total population), and 34 potential biomarkers (158,716 total population) for meta-analyses. The credibility of evidence was convincing (class I) for tic disorders (OR = 2.89, 95% CI 2.11-3.95); and highly suggestive (class II) for early-life antibiotic use (OR = 3.73, 95% CI 3.06-4.55), exposure to indoor dampness (OR = 1.49, 95% CI 1.27-1.75), acetaminophen exposure (OR = 1.54, 95% CI 1.41-1.69), childhood acid suppressant use (OR = 1.40, 95% CI 1.23-1.59), exposure to indoor mold (OR = 1.66, 95% CI 1.26-2.18), coronavirus disease 2019 (OR = 0.11, 95% CI 0.06-0.22), and prolonged breastfeeding (OR = 0.72, 95% CI 0.65-0.79). This study is registered in PROSPERO (CRD42022384320).
Topics: Child; Humans; Acetaminophen; Biomarkers; COVID-19; Protective Factors; Rhinitis, Allergic; Risk Factors; Systematic Reviews as Topic
PubMed: 37490237
DOI: 10.1007/s12016-023-08964-2 -
The Lancet. Psychiatry May 2020Prenatal and perinatal insults are implicated in the aetiopathogenesis of psychotic disorders but the consistency and magnitude of their associations with psychosis have... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Prenatal and perinatal insults are implicated in the aetiopathogenesis of psychotic disorders but the consistency and magnitude of their associations with psychosis have not been updated for nearly two decades. The aim of this systematic review and meta-analysis was to provide a comprehensive and up-to-date synthesis of the evidence on the association between prenatal or perinatal risk and protective factors and psychotic disorders.
METHODS
In this systematic review and meta-analysis, we searched the Web of Science database for articles published up to July 20, 2019. We identified cohort and case-control studies examining the association (odds ratio [OR]) between prenatal and perinatal factors and any International Classification of Diseases (ICD) or Diagnostic and Statistical Manual of Mental Disorders (DSM) non-organic psychotic disorder with a healthy comparison group. Other inclusion criteria were enough data available to do the analyses, and non-overlapping datasets. We excluded reviews, meta-analyses, abstracts or conference proceedings, and articles with overlapping datasets. Data were extracted according to EQUATOR and PRISMA guidelines. Extracted variables included first author, publication year, study type, sample size, type of psychotic diagnosis (non-affective psychoses or schizophrenia-spectrum disorders, affective psychoses) and diagnostic instrument (DSM or ICD and version), the risk or protective factor, and measure of association (primary outcome). We did random-effects pairwise meta-analyses, Q statistics, I index, sensitivity analyses, meta-regressions, and assessed study quality and publication bias. The study protocol was registered at PROSPERO, CRD42017079261.
FINDINGS
152 studies relating to 98 risk or protective factors were eligible for analysis. Significant risk factors were: maternal age younger than 20 years (OR 1·17) and 30-34 years (OR 1·05); paternal age younger than 20 years (OR 1·31) and older than 35 years (OR 1·28); any maternal (OR 4·60) or paternal (OR 2·73) psychopathology; maternal psychosis (OR 7·61) and affective disorder (OR 2·26); three or more pregnancies (OR 1·30); herpes simplex 2 (OR 1·35); maternal infections not otherwise specified (NOS; OR 1·27); suboptimal number of antenatal visits (OR 1·83); winter (OR 1·05) and winter to spring (OR 1·05) season of birth in the northern hemisphere; maternal stress NOS (OR 2·40); famine (OR 1·61); any famine or nutritional deficits in pregnancy (OR 1·40); maternal hypertension (OR 1·40); hypoxia (OR 1·63); ruptured (OR 1·86) and premature rupture (OR 2·29) of membranes; polyhydramnios (OR 3·05); definite obstetric complications NOS (OR 1·83); birthweights of less than 2000 g (OR 1·84), less than 2500 g (OR 1·53), or 2500-2999 g (OR 1·23); birth length less than 49 cm (OR 1·17); small for gestational age (OR 1·40); premature birth (OR 1·35), and congenital malformations (OR 2·35). Significant protective factors were maternal ages 20-24 years (OR 0·93) and 25-29 years (OR 0·92), nulliparity (OR 0·91), and birthweights 3500-3999 g (OR 0·90) or more than 4000 g (OR 0·86). The results were corrected for publication biases; sensitivity and meta-regression analyses confirmed the robustness of these findings for most factors.
INTERPRETATION
Several prenatal and perinatal factors are associated with the later onset of psychosis. The updated knowledge emerging from this study could refine understanding of psychosis pathogenesis, enhance multivariable risk prediction, and inform preventive strategies.
FUNDING
None.
Topics: Adult; Birth Weight; Congenital Abnormalities; Famine; Female; Fetal Macrosomia; Fetal Membranes, Premature Rupture; Herpes Simplex; Herpesvirus 2, Human; Humans; Hypertension; Hypoxia; Infant, Newborn; Infant, Small for Gestational Age; Male; Malnutrition; Maternal Age; Mood Disorders; Parity; Paternal Age; Polyhydramnios; Pregnancy; Pregnancy Complications; Pregnancy Complications, Infectious; Premature Birth; Prenatal Care; Prenatal Exposure Delayed Effects; Protective Factors; Psychotic Disorders; Risk Factors; Seasons; Stress, Psychological; Young Adult
PubMed: 32220288
DOI: 10.1016/S2215-0366(20)30057-2 -
Nutrients Jan 2018Heart failure (HF) is a complex syndrome and is recognized as the ultimate pathway of cardiovascular disease (CVD). Studies using nutritional strategies based on dietary... (Review)
Review
BACKGROUND
Heart failure (HF) is a complex syndrome and is recognized as the ultimate pathway of cardiovascular disease (CVD). Studies using nutritional strategies based on dietary patterns have proved to be effective for the prevention and treatment of CVD. Although there are studies that support the protective effect of these diets, their effects on the prevention of HF are not clear yet.
METHODS
We searched the Medline, Embase, and Cochrane databases for studies that examined dietary patterns, such as dietary approaches to stop hypertension (DASH diet), paleolithic, vegetarian, low-carb and low-fat diets and prevention of HF. No limitations were used during the search in the databases.
RESULTS
A total of 1119 studies were identified, 14 met the inclusion criteria. Studies regarding the Mediterranean, DASH, vegetarian, and Paleolithic diets were found. The Mediterranean and DASH diets showed a protective effect on the incidence of HF and/or worsening of cardiac function parameters, with a significant difference in relation to patients who did not adhere to these dietary patterns.
CONCLUSIONS
It is observed that the adoption of Mediterranean or DASH-type dietary patterns may contribute to the prevention of HF, but these results need to be analyzed with caution due to the low quality of evidence.
Topics: Adult; Aged; Aged, 80 and over; Diet, Healthy; Diet, Mediterranean; Diet, Paleolithic; Diet, Vegetarian; Dietary Approaches To Stop Hypertension; Feeding Behavior; Female; Heart Failure; Humans; Incidence; Male; Middle Aged; Nutritional Status; Nutritive Value; Primary Prevention; Protective Factors; Recommended Dietary Allowances; Risk Factors; Risk Reduction Behavior; Treatment Outcome
PubMed: 29320401
DOI: 10.3390/nu10010058 -
Clinical Psychology Review Feb 2023Autistic adults are a high-risk population for suicidal thoughts and behaviors (STBs). Accordingly, this systematic review aims to review the prevalence of STBs among... (Review)
Review
Autistic adults are a high-risk population for suicidal thoughts and behaviors (STBs). Accordingly, this systematic review aims to review the prevalence of STBs among autistic adults, review the risk and protective factors for STBs in autistic adults, and formulate a disorder-specific conceptualization of risk in this population. We systematically searched PsycINFO and Google Scholar for all studies published prior to March 28th, 2022. We included empirical articles focused on autistic adults, ages 18 years and older, reporting on suicide-related outcomes. In total, 45 peer-reviewed empirical articles were included in the current systematic review. The most frequently studied factors in relation to suicide risk among autistic adults were interpersonal constructs (42.4% of total studies looking at risk/protective factors) and depressive symptoms (36.4% of total studies looking at risk/protective factors). We conclude by summarize two key content areas: exploring social and interpersonal constructs and better understanding the role of depressive symptoms in autism. As researchers continue to explore STBs among autistic adults, it will be necessary to addressing the overreliance on autistic symptoms instead of autism diagnoses, measurement issues of STBs, and a need for treatment adaptations.
Topics: Adult; Humans; Adolescent; Suicidal Ideation; Autistic Disorder; Suicide, Attempted; Protective Factors; Suicide
PubMed: 36459876
DOI: 10.1016/j.cpr.2022.102235