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Journal of the Royal Society of Medicine Oct 2013We aimed to quantify the relationship between national income and infant and under-five mortality in developing countries. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
We aimed to quantify the relationship between national income and infant and under-five mortality in developing countries.
DESIGN
We conducted a systematic literature search of studies that examined the relationship between income and child mortality (infant and/or under-five mortality) and meta-analysed their results.
SETTING
Developing countries.
MAIN OUTCOME MEASURES
Child mortality (infant and /or under-five mortality).
RESULTS
The systematic literature search identified 24 studies, which produced 38 estimates that examined the impact of income on the mortality rates. Using meta-analysis, we produced pooled estimates of the relationship between income and mortality. The pooled estimate of the relationship between income and infant mortality before adjusting for covariates is -0.95 (95% CI -1.34 to -0.57) and that for under-five mortality is -0.45 (95% CI -0.79 to -0.11). After adjusting for covariates, pooled estimate of the relationship between income and infant mortality is -0.33 (-0.39 to -0.26) while the estimate for under-five mortality is -0.28 (-0.37 to -0.19). If a country has an infant mortality of 50 per 1000 live births and the gross domestic product per capita purchasing power parity increases by 10%, the infant mortality will decrease to 45 per 1000 live births.
CONCLUSION
Income is an important determinant of child survival and this work provides a pooled estimate for the relationship.
Topics: Child; Child Mortality; Child, Preschool; Developing Countries; Humans; Income; Infant; Infant Mortality
PubMed: 23824332
DOI: 10.1177/0141076813489680 -
The Cochrane Database of Systematic... Jun 2018Critically ill people are at increased risk of malnutrition. Acute and chronic illness, trauma and inflammation induce stress-related catabolism, and drug-induced... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Critically ill people are at increased risk of malnutrition. Acute and chronic illness, trauma and inflammation induce stress-related catabolism, and drug-induced adverse effects may reduce appetite or increase nausea and vomiting. In addition, patient management in the intensive care unit (ICU) may also interrupt feeding routines. Methods to deliver nutritional requirements include provision of enteral nutrition (EN), or parenteral nutrition (PN), or a combination of both (EN and PN). However, each method is problematic. This review aimed to determine the route of delivery that optimizes uptake of nutrition.
OBJECTIVES
To compare the effects of enteral versus parenteral methods of nutrition, and the effects of enteral versus a combination of enteral and parenteral methods of nutrition, among critically ill adults, in terms of mortality, number of ICU-free days up to day 28, and adverse events.
SEARCH METHODS
We searched CENTRAL, MEDLINE, and Embase on 3 October 2017. We searched clinical trials registries and grey literature, and handsearched reference lists of included studies and related reviews.
SELECTION CRITERIA
We included randomized controlled studies (RCTs) and quasi-randomized studies comparing EN given to adults in the ICU versus PN or versus EN and PN. We included participants that were trauma, emergency, and postsurgical patients in the ICU.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We assessed the certainty of evidence with GRADE.
MAIN RESULTS
We included 25 studies with 8816 participants; 23 studies were RCTs and two were quasi-randomized studies. All included participants were critically ill in the ICU with a wide range of diagnoses; mechanical ventilation status between study participants varied. We identified 11 studies awaiting classification for which we were unable to assess eligibility, and two ongoing studies.Seventeen studies compared EN versus PN, six compared EN versus EN and PN, two were multi-arm studies comparing EN versus PN versus EN and PN. Most studies reported randomization and allocation concealment inadequately. Most studies reported no methods to blind personnel or outcome assessors to nutrition groups; one study used adequate methods to reduce risk of performance bias.Enteral nutrition versus parenteral nutritionWe found that one feeding route rather than the other (EN or PN) may make little or no difference to mortality in hospital (risk ratio (RR) 1.19, 95% confidence interval (CI) 0.80 to 1.77; 361 participants; 6 studies; low-certainty evidence), or mortality within 30 days (RR 1.02, 95% CI 0.92 to 1.13; 3148 participants; 11 studies; low-certainty evidence). It is uncertain whether one feeding route rather than the other reduces mortality within 90 days because the certainty of the evidence is very low (RR 1.06, 95% CI 0.95 to 1.17; 2461 participants; 3 studies). One study reported mortality at one to four months and we did not combine this in the analysis; we reported this data as mortality within 180 days and it is uncertain whether EN or PN affects the number of deaths within 180 days because the certainty of the evidence is very low (RR 0.33, 95% CI 0.04 to 2.97; 46 participants).No studies reported number of ICU-free days up to day 28, and one study reported number of ventilator-free days up to day 28 and it is uncertain whether one feeding route rather than the other reduces the number of ventilator-free days up to day 28 because the certainty of the evidence is very low (mean difference, inverse variance, 0.00, 95% CI -0.97 to 0.97; 2388 participants).We combined data for adverse events reported by more than one study. It is uncertain whether EN or PN affects aspiration because the certainty of the evidence is very low (RR 1.53, 95% CI 0.46 to 5.03; 2437 participants; 2 studies), and we found that one feeding route rather than the other may make little or no difference to pneumonia (RR 1.10, 95% CI 0.82 to 1.48; 415 participants; 7 studies; low-certainty evidence). We found that EN may reduce sepsis (RR 0.59, 95% CI 0.37 to 0.95; 361 participants; 7 studies; low-certainty evidence), and it is uncertain whether PN reduces vomiting because the certainty of the evidence is very low (RR 3.42, 95% CI 1.15 to 10.16; 2525 participants; 3 studies).Enteral nutrition versus enteral nutrition and parenteral nutritionWe found that one feeding regimen rather than another (EN or combined EN or PN) may make little or no difference to mortality in hospital (RR 0.99, 95% CI 0.84 to 1.16; 5111 participants; 5 studies; low-certainty evidence), and at 90 days (RR 1.00, 95% CI 0.86 to 1.18; 4760 participants; 2 studies; low-certainty evidence). It is uncertain whether combined EN and PN leads to fewer deaths at 30 days because the certainty of the evidence is very low (RR 1.64, 95% CI 1.06 to 2.54; 409 participants; 3 studies). It is uncertain whether one feeding regimen rather than another reduces mortality within 180 days because the certainty of the evidence is very low (RR 1.00, 95% CI 0.65 to 1.55; 120 participants; 1 study).No studies reported number of ICU-free days or ventilator-free days up to day 28. It is uncertain whether either feeding method reduces pneumonia because the certainty of the evidence is very low (RR 1.40, 95% CI 0.91 to 2.15; 205 participants; 2 studies). No studies reported aspiration, sepsis, or vomiting.
AUTHORS' CONCLUSIONS
We found insufficient evidence to determine whether EN is better or worse than PN, or than combined EN and PN for mortality in hospital, at 90 days and at 180 days, and on the number of ventilator-free days and adverse events. We found fewer deaths at 30 days when studies gave combined EN and PN, and reduced sepsis for EN rather than PN. We found no studies that reported number of ICU-free days up to day 28. Certainty of the evidence for all outcomes is either low or very low. The 11 studies awaiting classification may alter the conclusions of the review once assessed.
Topics: Adult; Cause of Death; Combined Modality Therapy; Critical Illness; Enteral Nutrition; Hospital Mortality; Humans; Intensive Care Units; Malnutrition; Parenteral Nutrition; Pneumonia; Randomized Controlled Trials as Topic; Time Factors; Vomiting
PubMed: 29883514
DOI: 10.1002/14651858.CD012276.pub2 -
Nutrients Apr 2023Mortality is the most clinically serious outcome, and its prevention remains a constant struggle. This study was to assess whether intravenous or oral vitamin C (Vit-C)... (Meta-Analysis)
Meta-Analysis Review
Mortality is the most clinically serious outcome, and its prevention remains a constant struggle. This study was to assess whether intravenous or oral vitamin C (Vit-C) therapy is related to reduced mortality in adults. Data from Medline, Embase, and the Cochrane Central Register databases were acquired from their inception to 26 October 2022. All randomized controlled trials (RCTs) involving intravenous or oral Vit-C against a placebo or no therapy for mortality were selected. The primary outcome was all-cause mortality. Secondary outcomes were sepsis, COVID-19, cardiac surgery, noncardiac surgery, cancer, and other mortalities. Forty-four trials with 26540 participants were selected. Although a substantial statistical difference was observed in all-cause mortality between the control and the Vit-C-supplemented groups ( = 0.009, RR 0.87, 95% CI 0.78 to 0.97, I = 36%), the result was not validated by sequential trial analysis. In the subgroup analysis, mortality was markedly reduced in Vit-C trials with the sepsis patients ( = 0.005, RR 0.74, 95% CI 0.59 to 0.91, I = 47%), and this result was confirmed by trial sequential analysis. In addition, a substantial statistical difference was revealed in COVID-19 patient mortality between the Vit-C monotherapy and the control groups ( = 0.03, RR 0.84, 95% CI 0.72 to 0.98, I = 0%). However, the trial sequential analysis suggested the need for more trials to confirm its efficacy. Overall, Vit-C monotherapy does decrease the risk of death by sepsis by 26%. To confirm Vit-C is associated with reduced COVID-19 mortality, additional clinical random control trials are required.
Topics: Adult; Humans; Ascorbic Acid; Cause of Death; COVID-19; Vitamins; Dietary Supplements
PubMed: 37111066
DOI: 10.3390/nu15081848 -
American Journal of Public Health Dec 2012We systematically reviewed studies of mortality following release from prison and examined possible demographic and methodological factors associated with variation in... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
We systematically reviewed studies of mortality following release from prison and examined possible demographic and methodological factors associated with variation in mortality rates.
METHODS
We searched 5 computer-based literature indexes to conduct a systematic review of studies that reported all-cause, drug-related, suicide, and homicide deaths of released prisoners. We extracted and meta-analyzed crude death rates and standardized mortality ratios by age, gender, and race/ethnicity, where reported.
RESULTS
Eighteen cohorts met review criteria reporting 26,163 deaths with substantial heterogeneity in rates. The all-cause crude death rates ranged from 720 to 2054 per 100,000 person-years. Male all-cause standardized mortality ratios ranged from 1.0 to 9.4 and female standardized mortality ratios from 2.6 to 41.3. There were higher standardized mortality ratios in White, female, and younger prisoners.
CONCLUSIONS
Released prisoners are at increased risk for death following release from prison, particularly in the early period. Aftercare planning for released prisoners could potentially have a large public health impact, and further work is needed to determine whether certain groups should be targeted as part of strategies to reduce mortality.
Topics: Adult; Age Factors; Aged; Female; Homicide; Humans; Male; Middle Aged; Mortality; Prisoners; Risk Factors; Sex Factors; Substance-Related Disorders; Suicide; Young Adult
PubMed: 23078476
DOI: 10.2105/AJPH.2012.300764 -
Medical Care Feb 2018An association between weekend health care delivery and poor outcomes has become known as the "weekend effect." Evidence for such an association among surgery patients... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
An association between weekend health care delivery and poor outcomes has become known as the "weekend effect." Evidence for such an association among surgery patients has not previously been synthesized.
OBJECTIVE
To systematically review associations between weekend surgical care and postoperative mortality.
METHODS
We searched PubMed, EMBASE, and references of relevant articles for studies that compared postoperative mortality either; (1) according to the day of the week of surgery for elective operations, or (2) according to weekend versus weekday admission for urgent/emergent operations. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for postoperative mortality (≤90 d or inpatient mortality) were pooled using random-effects models.
RESULTS
Among 4027 citations identified, 10 elective surgery studies and 19 urgent/emergent surgery studies with a total of >6,685,970 and >1,424,316 patients, respectively, met the inclusion criteria. Pooled odds of mortality following elective surgery rose in a graded manner as the day of the week of surgery approached the weekend [Monday OR=1 (reference); Tuesday OR=1.04 (95% CI=0.97-1.11); Wednesday OR=1.08 (95% CI=0.98-1.19); Thursday OR=1.12 (95% CI=1.03-1.22); Friday OR=1.24 (95% CI=1.10-1.38)]. Mortality was also higher among patients who underwent urgent/emergent surgery after admission on the weekend relative to admission on weekdays (OR=1.27; 95% CI=1.08-1.49).
CONCLUSIONS
Postoperative mortality rises as the day of the week of elective surgery approaches the weekend, and is higher after admission for urgent/emergent surgery on the weekend compared with weekdays. Future research should focus on clarifying underlying causes of this association and potentially mitigating its impact.
Topics: After-Hours Care; Cohort Studies; Databases, Factual; Elective Surgical Procedures; Female; Hospital Mortality; Hospitalization; Humans; Length of Stay; Male; Postoperative Period; Surgical Procedures, Operative; Time Factors
PubMed: 29251716
DOI: 10.1097/MLR.0000000000000860 -
Eastern Mediterranean Health Journal =... May 2023Maternal mortality is an indication of the health status of women in the society. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Maternal mortality is an indication of the health status of women in the society.
AIMS
To investigate the maternal mortality ratio, causes of maternal mortality, and related risk factors among Iranian women.
METHODS
Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and the Peer Review of Electronic Search Strategies (PRESS) guideline, we systematically searched electronic databases, and the grey literature, for publications in Farsi and English from 1970 to January 2022 for studies that reported the number of maternal deaths and/or maternal mortality ratio and their related factors. Data analysis was conducted using Stata 16 and 2-sided P ≤ 0.05 was considered statistically significant, if not otherwise specified.
RESULTS
A subgroup meta-analysis of studies conducted since 2000 estimated the maternal mortality ratio as 45.03 per 100 000 births during 2000-2004, 36.05 during 2005-2009, and 23.71 after 2010. The most frequent risk factors for maternal mortality were caesarean section, poor antenatal and delivery care, unskilled birth attendance, age, low maternal education level, lower human development index, and residence in rural or remote areas.
CONCLUSION
There has been a significant decrease in maternal mortality in the Islamic Republic of Iran during the last few decades. Mothers in the country need to be monitored more carefully by trained healthcare workers during the pregnancy, delivery and postpartum periods so they can effectively handle postpartum complications, such as haemorrhage and infection, thereby further reducing maternal mortality.
Topics: Pregnancy; Humans; Female; Maternal Mortality; Iran; Cesarean Section; Checklist; Databases, Factual
PubMed: 37306175
DOI: 10.26719/emhj.23.063 -
Medicine Sep 2017In this study, we evaluated whether increased risks of mortality and cancer incidence exist among butchers worldwide. To achieve this goal, we conducted a systematic... (Review)
Review
BACKGROUND
In this study, we evaluated whether increased risks of mortality and cancer incidence exist among butchers worldwide. To achieve this goal, we conducted a systematic review and meta-analysis to investigate the correlations of the risks of cancer death and incidence with male and female butchers.
METHODS
We obtained data by performing a comprehensive literature search in several databases for eligible studies published before March 2017. Multivariable-adjusted standardized mortality ratios (SMRs) and odds ratio (OR), as well as associated 95% confidence intervals (CIs) and those by subgroups, were extracted and pooled.
RESULTS
A total of 17 observational studies comprising 397,726 participants were included in the meta-analysis. The butcher occupation was not associated with all-cancer mortality risk, with pooled overall SMRs of 1.07 (95% CI 0.96-1.20). However, the pooled ORs revealed that butchers hold an elevated risk of total cancer incidence (OR, 1.51; 95% CI, 1.33-1.73). No proof of publication bias was obtained, and the findings were consistent in the subgroup analyses.
CONCLUSION
Our results suggest that working as butchers did not significantly influence all-cancer mortality risk but significantly contributed to elevated all-cancer incidence risk. Nevertheless, well-designed observational studies on this topic are necessary to confirm and update our findings.
Topics: Humans; Incidence; Meat Products; Meat-Packing Industry; Mortality; Neoplasms; Occupational Exposure; Risk Factors
PubMed: 28953674
DOI: 10.1097/MD.0000000000008177 -
International Journal of Environmental... Nov 2017The latest nationwide survey of Pakistan showed that considerable progress has been made toward reducing all child mortality indicators except neonatal mortality. The... (Review)
Review
The latest nationwide survey of Pakistan showed that considerable progress has been made toward reducing all child mortality indicators except neonatal mortality. The aim of this study is to compare Pakistan's under-five mortality, neonatal mortality, and postnatal newborn care rates with those of other countries. Neonatal mortality rates and postnatal newborn care rates from the Demographic and Health Surveys (DHSs) of nine low- and middle-income countries (LMIC) from Asia and Africa were analyzed. Pakistan's maternal, newborn, and child health (MNCH) policies and programs, which have been implemented in the country since 1990, were also analyzed. The results highlighted that postnatal newborn care in Pakistan was higher compared with the rest of countries, yet its neonatal mortality remained the worst. In Zimbabwe, both mortality rates have been increasing, whereas the neonatal mortality rates in Nepal and Afghanistan remained unchanged. An analysis of Pakistan's MNCH programs showed that there is no nationwide policy on neonatal health. There were only a few programs concerning the health of newborns, and those were limited in scale. Pakistan's example shows that increased coverage of neonatal care without ensuring quality is unlikely to improve neonatal survival rates. It is suggested that Pakistan needs a comprehensive policy on neonatal health similar to other countries, and its effective programs need to be scaled up, in order to obtain better neonatal health outcomes.
Topics: Child Health Services; Child Mortality; Child, Preschool; Developing Countries; Health Policy; Humans; Infant; Infant Health; Infant Mortality; Infant, Newborn; Pakistan; Perinatal Mortality; Program Evaluation; Surveys and Questionnaires
PubMed: 29168764
DOI: 10.3390/ijerph14121442 -
International Journal of Epidemiology Jun 2011A number of prospective cohort studies have examined the association between intelligence in childhood or youth and life expectancy in adulthood; however, the effect... (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND
A number of prospective cohort studies have examined the association between intelligence in childhood or youth and life expectancy in adulthood; however, the effect size of this association is yet to be quantified and previous reviews require updating.
METHODS
The systematic review included an electronic search of EMBASE, MEDLINE and PSYCHINFO databases. This yielded 16 unrelated studies that met inclusion criteria, comprising 22,453 deaths among 1,107,022 participants. Heterogeneity was assessed, and fixed effects models were applied to the aggregate data. Publication bias was evaluated, and sensitivity analyses were conducted.
RESULTS
A 1-standard deviation (SD) advantage in cognitive test scores was associated with a 24% (95% confidence interval 23-25) lower risk of death, during a 17- to 69-year follow-up. There was little evidence of publication bias (Egger's intercept = 0.10, P = 0.81), and the intelligence-mortality association was similar for men and women. Adjustment for childhood socio-economic status (SES) in the nine studies containing these data had almost no impact on this relationship, suggesting that this is not a confounder of the intelligence-mortality association. Controlling for adult SES in five studies and for education in six studies attenuated the intelligence-mortality hazard ratios by 34 and 54%, respectively.
CONCLUSIONS
Future investigations should address the extent to which attenuation of the intelligence-mortality link by adult SES indicators is due to mediation, over-adjustment and/or confounding. The explanation(s) for association between higher early-life intelligence and lower risk of adult mortality require further elucidation.
Topics: Adolescent; Age Distribution; Cause of Death; Child; Cohort Studies; Educational Status; Female; Humans; Incidence; Intelligence; Longitudinal Studies; Male; Mortality; Prospective Studies; Risk Assessment; Sex Distribution; Social Class; United States; Young Adult
PubMed: 21037248
DOI: 10.1093/ije/dyq190 -
The Lancet. Public Health Mar 2024The positive effect of education on reducing all-cause adult mortality is known; however, the relative magnitude of this effect has not been systematically quantified.... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The positive effect of education on reducing all-cause adult mortality is known; however, the relative magnitude of this effect has not been systematically quantified. The aim of our study was to estimate the reduction in all-cause adult mortality associated with each year of schooling at a global level.
METHODS
In this systematic review and meta-analysis, we assessed the effect of education on all-cause adult mortality. We searched PubMed, Web of Science, Scopus, Embase, Global Health (CAB), EconLit, and Sociology Source Ultimate databases from Jan 1, 1980, to May 31, 2023. Reviewers (LD, TM, HDV, CW, IG, AG, CD, DS, KB, KE, and AA) assessed each record for individual-level data on educational attainment and mortality. Data were extracted by a single reviewer into a standard template from the Global Burden of Diseases, Injuries, and Risk Factors Study. We excluded studies that relied on case-crossover or ecological study designs to reduce the risk of bias from unlinked data and studies that did not report key measures of interest (all-cause adult mortality). Mixed-effects meta-regression models were implemented to address heterogeneity in referent and exposure measures among studies and to adjust for study-level covariates. This study was registered with PROSPERO (CRD42020183923).
FINDINGS
17 094 unique records were identified, 603 of which were eligible for analysis and included data from 70 locations in 59 countries, producing a final dataset of 10 355 observations. Education showed a dose-response relationship with all-cause adult mortality, with an average reduction in mortality risk of 1·9% (95% uncertainty interval 1·8-2·0) per additional year of education. The effect was greater in younger age groups than in older age groups, with an average reduction in mortality risk of 2·9% (2·8-3·0) associated with each additional year of education for adults aged 18-49 years, compared with a 0·8% (0·6-1·0) reduction for adults older than 70 years. We found no differential effect of education on all-cause mortality by sex or Socio-demographic Index level. We identified publication bias (p<0·0001) and identified and reported estimates of between-study heterogeneity.
INTERPRETATION
To our knowledge, this is the first systematic review and meta-analysis to quantify the importance of years of schooling in reducing adult mortality, the benefits of which extend into older age and are substantial across sexes and economic contexts. This work provides compelling evidence of the importance of education in improving life expectancy and supports calls for increased investment in education as a crucial pathway for reducing global inequities in mortality.
FUNDING
Research Council of Norway and the Bill & Melinda Gates Foundation.
Topics: Adult; Humans; Databases, Factual; Educational Status; Life Expectancy; Norway; Mortality
PubMed: 38278172
DOI: 10.1016/S2468-2667(23)00306-7