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Environment International Jan 2021South Asia is highly vulnerable to climate change and is projected to experience some of the highest increases in average annual temperatures throughout the century.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
South Asia is highly vulnerable to climate change and is projected to experience some of the highest increases in average annual temperatures throughout the century. Although the adverse impacts of ambient temperature on human health have been extensively documented in the literature, only a limited number of studies have focused on populations in this region.
OBJECTIVES
Our aim was to systematically review the current state and quality of available evidence on the direct relationship between ambient temperature and heat waves and all-cause mortality in South Asia.
METHODS
The databases Pubmed, Web of Science, Scopus and Embase were searched from 1990 to 2020 for relevant observational quantitative studies. We applied the Navigation Guide methodology to assess the strength of the evidence and performed a meta-analysis based on a novel approach that allows for combining nonlinear exposure-response associations without access to data from individual studies.
RESULTS
From the 6,759 screened papers, 27 were included in the qualitative synthesis and five in a meta-analysis. Studies reported an association of all-cause mortality with heat wave episodes and both high and low daily temperatures. The meta-analysis showed a U-shaped pattern, with increasing mortality for both high and low temperatures, but a statistically significant association was found only at higher temperatures - above 31° C for lag 0-1 days and above 34° C for lag 0-13 days. Effects were found to vary with cause of death, age, sex, location (urban vs. rural), level of education and socio-economic status, but the profile of vulnerabilities was somewhat inconsistent and based on a limited number of studies. Overall, the strength of the evidence for ambient temperature as a risk factor for all-cause mortality was judged as limited and for heat wave episodes as inadequate.
CONCLUSIONS
The evidence base on temperature impacts on mortality in South Asia is limited due to the small number of studies, their skewed geographical distribution and methodological weaknesses. Understanding the main determinants of the temperature-mortality association as well as how these may evolve in the future in a dynamic region such as South Asia will be an important area for future research. Studies on viable adaptation options to high temperatures for a region that is a hotspot for climate vulnerability, urbanisation and population growth are also needed.
Topics: Asia; Climate Change; Cold Temperature; Hot Temperature; Humans; Mortality; Temperature
PubMed: 33395923
DOI: 10.1016/j.envint.2020.106170 -
Social Science & Medicine (1982) Mar 2011Unemployment rates in the United States remain near a 25-year high and global unemployment is rising. Previous studies have shown that unemployed persons have an... (Meta-Analysis)
Meta-Analysis Review
Unemployment rates in the United States remain near a 25-year high and global unemployment is rising. Previous studies have shown that unemployed persons have an increased risk of death, but the magnitude of the risk and moderating factors have not been explored. The study is a random effects meta-analysis and meta-regression designed to assess the association between unemployment and all-cause mortality among working-age persons. We extracted 235 mortality risk estimates from 42 studies, providing data on more than 20 million persons. The mean hazard ratio (HR) for mortality was 1.63 among HRs adjusted for age and additional covariates. The mean effect was higher for men than for women. Unemployment was associated with an increased mortality risk for those in their early and middle careers, but less for those in their late career. The risk of death was highest during the first 10 years of follow-up, but decreased subsequently. The mean HR was 24% lower among the subset of studies controlling for health-related behaviors. Public health initiatives could target unemployed persons for more aggressive cardiovascular screening and interventions aimed at reducing risk-taking behaviors.
Topics: Adult; Aged; Cause of Death; Female; Humans; Male; Middle Aged; Mortality; Stress, Psychological; Unemployment
PubMed: 21330027
DOI: 10.1016/j.socscimed.2011.01.005 -
Acta Obstetricia Et Gynecologica... Feb 2020Severe early-onset fetal growth restriction is an obstetric condition with significant risks of perinatal mortality, major and minor neonatal morbidity, and long-term...
INTRODUCTION
Severe early-onset fetal growth restriction is an obstetric condition with significant risks of perinatal mortality, major and minor neonatal morbidity, and long-term health sequelae. The prognosis of a fetus is influenced by the extent of prematurity and fetal weight. Clinical care is individually adjusted. In literature, survival rates vary and studies often only include live-born neonates with missing rates of antenatal death. This systematic review aims to summarize the literature on mortality and morbidity.
MATERIAL AND METHODS
A broad literature search was conducted in OVID MEDLINE from 2000 to 26 April 2019 to identify studies on fetal growth restriction and perinatal death. Studies were excluded when all included children were born before 2000 because (neonatal) health care has considerably improved since this period. Studies were included that described fetal growth restriction diagnosed before 32 weeks of gestation and antenatal mortality and neonatal mortality and/or morbidity as outcome. Quality of evidence was rated with the GRADE instrument.
RESULTS
Of the 2604 publications identified, 25 studies, reporting 2895 pregnancies, were included in the systematic review. Overall risk of bias in most studies was judged as low. The quality of evidence was generally rated as very low to moderate, except for 3 large well-designed randomized controlled trials. When combining all data on mortality, in 355 of 2895 pregnancies (12%) the fetus died antenatally, 192 died in the neonatal period (8% of live-born neonates) and 2347 (81% of all pregnancies) children survived. Of the neonatal morbidities recorded, respiratory distress syndrome (34% of the live-born neonates), retinopathy of prematurity (13%) and sepsis (30%) were most common. Of 476 children that underwent neurodevelopmental assessment, 58 (12% of surviving children, 9% of all pregnancies) suffered from cognitive impairment and/or cerebral palsy.
CONCLUSIONS
When combining the data of 25 included studies, survival in fetal growth restriction pregnancies, diagnosed before 32 weeks of gestation, was 81%. Neurodevelopmental impairment was assessed in a minority of surviving children. Individual prognostic counseling on the basis of these results is hampered by differences in patient and pregnancy characteristics within the included patient groups.
Topics: Female; Fetal Death; Fetal Growth Retardation; Gestational Age; Humans; Infant, Newborn; Infant, Newborn, Diseases; Perinatal Mortality; Pregnancy; Prognosis
PubMed: 31376293
DOI: 10.1111/aogs.13702 -
International Journal of Epidemiology Oct 2011The dose-response relation between physical activity and all-cause mortality is not well defined at present. We conducted a systematic review and meta-analysis to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The dose-response relation between physical activity and all-cause mortality is not well defined at present. We conducted a systematic review and meta-analysis to determine the association with all-cause mortality of different domains of physical activity and of defined increases in physical activity and energy expenditure.
METHODS
MEDLINE, Embase and the Cochrane Library were searched up to September 2010 for cohort studies examining all-cause mortality across different domains and levels of physical activity in adult general populations. We estimated combined risk ratios (RRs) associated with defined increments and recommended levels, using random-effects meta-analysis and dose-response meta-regression models.
RESULTS
Data from 80 studies with 1 338 143 participants (118 121 deaths) were included. Combined RRs comparing highest with lowest activity levels were 0.65 [95% confidence interval (95% CI) 0.60-0.71] for total activity, 0.74 (95% CI 0.70-0.77) for leisure activity, 0.64 (95% CI 0.55-0.75) for activities of daily living and 0.83 (95% CI 0.71-0.97) for occupational activity. RRs per 1-h increment per week were 0.91 (95% CI 0.87-0.94) for vigorous exercise and 0.96 (95% CI 0.93-0.98) for moderate-intensity activities of daily living. RRs corresponding to 150 and 300 min/week of moderate to vigorous activity were 0.86 (95% CI 0.80-0.92) and 0.74 (95% CI 0.65-0.85), respectively. Mortality reductions were more pronounced in women.
CONCLUSION
Higher levels of total and domain-specific physical activity were associated with reduced all-cause mortality. Risk reduction per unit of time increase was largest for vigorous exercise. Moderate-intensity activities of daily living were to a lesser extent beneficial in reducing mortality.
Topics: Adult; Age Distribution; Aged; Aged, 80 and over; Cause of Death; Cohort Studies; Energy Metabolism; Exercise; Female; Humans; Leisure Activities; Male; Middle Aged; Mortality; Motor Activity; Sex Distribution; Sports; Young Adult
PubMed: 22039197
DOI: 10.1093/ije/dyr112 -
Allopurinol to reduce cardiovascular morbidity and mortality: A systematic review and meta-analysis.PloS One 2021To compare the effectiveness of allopurinol with no treatment or placebo for the prevention of cardiovascular events in hyperuricemic patients. (Meta-Analysis)
Meta-Analysis
AIMS
To compare the effectiveness of allopurinol with no treatment or placebo for the prevention of cardiovascular events in hyperuricemic patients.
METHODS AND RESULTS
Pubmed, Web of Science and Cochrane library were searched from inception until July 2020. Randomized controlled trials (RCT) and observational studies in hyperuricemic patients without significant renal disease and treated with allopurinol, versus placebo or no treatment were included. Outcome measures were cardiovascular mortality, myocardial infarction, stroke, or a combined endpoint (CM/MI/S). For RCT's a random effects meta-analysis was performed. For observational studies a narrative synthesis was performed. Of the original 1995 references we ultimately included 26 RCT's and 21 observational studies. We found a significantly reduced risk of combined endpoint (Risk Ratio 0.65 [95% CI] [0.46 to 0.91]; p = 0.012) and myocardial infarction (RR 0.47 [0.27 to 0.80]; p = 0.01) in the allopurinol group compared to controls. We found no significant effect of allopurinol on stroke or cardiovascular mortality. Of the 15 observational studies with sufficient quality, allopurinol was associated with reduced cardiovascular mortality in 1 out of 3 studies that reported this outcome, myocardial infarction in 6 out of 8, stroke in 4 out of 7, and combined end-point in 2 out of 2. Cardiovascular benefit was only observed when allopurinol therapy was prolonged for more than 6 months and when an appropriate allopurinol dose was administered (300 mg or more/day) or sufficient reduction of serum urate concentration was achieved (<0.36 mmol/l).
CONCLUSIONS
Data from RCT's and observational studies indicate that allopurinol treatment reduces cardiovascular risk in patients with hyperuricemia. However, the quality of evidence from RCTs is low to moderate. To establish whether allopurinol lowers the risk of cardiovascular events a well-designed and adequately powered randomized, placebo-controlled trial is needed in high-risk patients with hyperuricemia.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO registration CRD42018089744.
Topics: Allopurinol; Antimetabolites; Cardiovascular Diseases; Humans; Morbidity; Prognosis; Survival Rate
PubMed: 34855873
DOI: 10.1371/journal.pone.0260844 -
Bulletin of the World Health... Apr 2017To investigate, within so-called general populations, the relationship between maternal survival and mortality of children younger than five years. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To investigate, within so-called general populations, the relationship between maternal survival and mortality of children younger than five years.
METHODS
We conducted a systematic review of literature published between January 1990 and November 2016 that reported maternal vital status and the corresponding mortality of children younger than five years. Seven studies were included in a qualitative analysis and four in a random-effects meta-analysis. Summary estimates of the odds of dying by maternal survival were obtained and statistical heterogeneity estimated. Quality of the included studies and evidence was assessed using a Cochrane tool for assessing risk of bias and the Grading of Recommendations Assessment, Development and Evaluation criteria, respectively.
FINDINGS
Among children younger than five years, those whose mother had died were found to be 4.09 times (95% confidence interval, CI: 2.40-6.98) more likely to die than those with surviving mothers. Due to heterogeneity (I: 83%), further pooled estimates were not possible. For children that were motherless as a result of maternal mortality, the increased odds of dying ranged from 1.40 (95% CI: 0.47-4.21) to 2.92 (95% CI: 1.21-7.04) among those aged between two and four years, 6.1 (95% CI: 2.27-16.77) to 33.78 (95% CI: 24.21-47.14) for those younger than one year and 4.39 (95% CI: 3.34-5.78) to 51.68 (95% CI: 20.26-131.80) for those younger than six months.
CONCLUSION
The loss of a mother was associated with increased mortality among children, especially when maternal death occurred in the first year of the child's life.
Topics: Child Mortality; Child, Preschool; Humans; Infant; Infant Mortality; Infant, Newborn; Maternal Death; Mothers; Survivors
PubMed: 28479623
DOI: 10.2471/BLT.15.157149 -
BMJ Open Feb 2016While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality.
METHODS
Cohort studies published in peer-reviewed journals indexed in EMBASE and MEDLINE to September 2015 and PubMed to October 2015 and cited in reviews/key publications were identified via search strings using terms relating to study design, pollutant and health outcome. Study details and estimate information were extracted and used to calculate standardised effect estimates expressed as HRs per 10 ppb increment in long-term ozone concentrations.
RESULTS
14 publications from 8 cohorts presented results for ozone and all-cause and cause-specific mortality. We found no evidence of associations between long-term annual O3 concentrations and the risk of death from all causes, cardiovascular or respiratory diseases, or lung cancer. 4 cohorts assessed ozone concentrations measured during the warm season. Summary HRs for cardiovascular and respiratory causes of death derived from 3 cohorts were 1.01 (95% CI 1.00 to 1.02) and 1.03 (95% CI 1.01 to 1.05) per 10 ppb, respectively.
CONCLUSIONS
Our quantitative review revealed a paucity of independent studies regarding the associations between long-term exposure to ozone and mortality. The potential impact of climate change and increasing anthropogenic emissions of ozone precursors on ozone levels worldwide suggests further studies of the long-term effects of exposure to high ozone levels are warranted.
Topics: Air Pollutants; Air Pollution; Cardiovascular Diseases; Cause of Death; Cohort Studies; Humans; Mortality; Ozone; Respiratory Tract Diseases; Risk Factors; Seasons; Time Factors
PubMed: 26908518
DOI: 10.1136/bmjopen-2015-009493 -
PloS One 2014Home visits for older adults aim to prevent cognitive and functional impairment, thus reducing institutionalization and mortality. Visitors may provide information,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Home visits for older adults aim to prevent cognitive and functional impairment, thus reducing institutionalization and mortality. Visitors may provide information, investigate untreated problems, encourage medication compliance, and provide referrals to services.
DATA SOURCES
Ten databases including CENTRAL and Medline searched through December 2012.
STUDY SELECTION
Randomized controlled trials enrolling community-dwelling persons without dementia aged over 65 years. Interventions included visits at home by a health or social care professional that were not related to hospital discharge.
DATA EXTRACTION AND SYNTHESIS
Two authors independently extracted data. Outcomes were pooled using random effects.
MAIN OUTCOMES AND MEASURES
Mortality, institutionalization, hospitalization, falls, injuries, physical functioning, cognitive functioning, quality of life, and psychiatric illness.
RESULTS
Sixty-four studies with 28642 participants were included. Home visits were not associated with absolute reductions in mortality at longest follow-up, but some programs may have small relative effects (relative risk = 0.93 [0.87 to 0.99]; absolute risk = 0.00 [-0.01 to 0.00]). There was moderate quality evidence of no overall effect on the number of people institutionalized (RR = 1.02 [0.88 to 1.18]) or hospitalized (RR = 0.96 [0.91 to 1.01]). There was high quality evidence for number of people who fell, which is consistent with no effect or a small effect (odds ratio = 0.86 [0.73 to 1.01]), but there was no evidence that these interventions increased independent living. There was low and very low quality evidence of effects for quality of life (standardised mean difference = -0.06 [-0.11 to -0.01]) and physical functioning (SMD = -0.10 [-0.17 to -0.03]) respectively, but these may not be clinically important.
CONCLUSIONS
Home visiting is not consistently associated with differences in mortality or independent living, and investigations of heterogeneity did not identify any programs that are associated with consistent benefits. Due to poor reporting of intervention components and delivery, we cannot exclude the possibility that some programs may be effective.
Topics: Aged; House Calls; Humans; Institutionalization; Morbidity; Mortality
PubMed: 24622676
DOI: 10.1371/journal.pone.0089257 -
PloS One 2018Pregnancy-related critical illness leads to death for 3-14% of affected women. Although identifying patients at risk could facilitate preventive strategies, guide... (Meta-Analysis)
Meta-Analysis
PURPOSE
Pregnancy-related critical illness leads to death for 3-14% of affected women. Although identifying patients at risk could facilitate preventive strategies, guide therapy, and help in clinical research, no prior systematic review of this literature exploring the validity of risk prediction models for maternal mortality exists. Therefore, we have systematically reviewed and meta-analyzed risk prediction models for maternal mortality.
METHODS
Search strategy: MEDLINE, EMBASE and Scopus, from inception to May 2017. Selection criteria: Trials or observational studies evaluating risk prediction models for maternal mortality. Data collection and analysis: Two reviewers independently assessed studies for eligibility and methodological quality, and extracted data on prediction performance.
RESULTS
Thirty-eight studies that evaluated 12 different mortality prediction models were included. Mortality varied across the studies, with an average rate 10.4%, ranging from 0 to 41.7%. The Collaborative Integrated Pregnancy High-dependency Estimate of Risk (CIPHER) model and the Maternal Severity Index had the best performance, were developed and validated from studies of obstetric population with a low risk of bias. The CIPHER applies to critically ill obstetric patients (discrimination: area under the receiver operating characteristic curve (AUC) 0.823 (0.811-0.835), calibration: graphic plot [intercept-0.09, slope 0.92]). The Maternal Severity Index applies to hospitalized obstetric patients (discrimination: AUC 0.826 [0.802-0.851], calibration: standardized mortality ratio 1.02 [0.86-1.20]).
CONCLUSIONS
Despite the high heterogeneity of the study populations and the limited number of studies validating the finally eligible prediction models, the CIPHER and the Maternal Severity Index are recommended for use among critically ill and hospitalized pregnant and postpartum women for risk adjustment in clinical research and quality improvement studies. Neither index has sufficient discrimination to be applicable for clinical decision making at the individual patient level.
Topics: Area Under Curve; Critical Illness; Databases, Factual; Delivery, Obstetric; Female; Humans; Maternal Mortality; Pregnancy; ROC Curve; Risk
PubMed: 30513118
DOI: 10.1371/journal.pone.0208563 -
Revista de Saude Publica Apr 2012To describe methods of estimation and assess preventable deaths and types of errors related to health care. (Review)
Review
OBJECTIVE
To describe methods of estimation and assess preventable deaths and types of errors related to health care.
METHODS
A systematic review of articles on preventable trauma deaths published between 2000 and 2009 was conducted. Lilacs, SciELO and Medline databases were searched using the keywords "trauma," "avoidable," "preventable," "interventions" and "complications" and the health sciences descriptors "death," "cause of death," and "hospitals."
RESULTS
A total of 29 articles published during the study period were selected. Most were retrospective studies (96.5%). The most common methods used to define avoidability of death were expert panel and injury severity scores. Deaths were categorized as follows: preventable; potentially preventable; and not preventable. The mean preventable death rate was 10.7% (SD 11.5%). The most commonly reported errors were inadequate care management of injured patients and evaluation and treatment errors.
CONCLUSIONS
Inconsistent terms were used to categorize deaths and related noncompliances. It is suggested to standardize the terminology for the classification of deaths and types of errors.
Topics: Biomedical Research; Cause of Death; Databases, Bibliographic; Hospital Mortality; Humans; Medical Errors; Quality of Health Care; Trauma Severity Indices; Wounds and Injuries
PubMed: 22310649
DOI: 10.1590/s0034-89102012005000010