Summary Background Deaths from suicide are a tragic yet preventable cause of mortality. Quantifying the burden of suicide to understand its geographical distribution, temporal trends, and variation by age and sex is an essential step in suicide prevention. We aimed to present a comprehensive set of global, regional, and national estimates of suicide burden. Methods We produced estimates of the number of deaths and age-standardised mortality rates of suicide globally, regionally, and for 204 countries and territories from 1990 to 2021, and disaggregated these results by age and sex. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 estimates of deaths attributable to suicide were broken down into two comprehensive categories: those by firearms and those by other specified means. For this analysis, we also produced estimates of mean age at the time of death from suicide, incidence of suicide attempts compared with deaths, and age-standardised rates of suicide by firearm. We acquired data from vital registration, verbal autopsy, and mortality surveillance that included 23 782 study-location-years of data from GBD 2021. Point estimates were calculated from the average of 1000 randomly selected possible values of deaths from suicide by age, sex, and geographical location. 95% uncertainty intervals (UIs) were derived from the 2·5th and 97·5th percentiles from a 1000-draw distribution. Findings Globally, 746 000 deaths (95% UI 692 000–800 000) from suicide occurred in 2021, including 519 000 deaths (485 000–556 000) among males and 227 000 (200 000–255 000) among females. The age-standardised mortality rate has declined over time, from 14·9 deaths (12·8–15·7) per 100 000 population in 1990 to 9·0 (8·3–9·6) per 100 000 in 2021. Regionally, mortality rates due to suicide were highest in eastern Europe (19·2 [17·5–20·8] per 100 000), southern sub-Saharan Africa (16·1 [14·0–18·3] per 100 000), and central sub-Saharan Africa (14·4 [11·0–19·1] per 100 000). The mean age at which individuals died from suicide progressively increased during the study period. For males, the mean age at death by suicide in 1990 was 43·0 years (38·0–45·8), increasing to 47·0 years (43·5–50·6) in 2021. For females, it was 41·9 years (30·9–46·7) in 1990 and 46·9 years (41·2–52·8) in 2021. The incidence of suicide attempts requiring medical care was consistently higher at the regional level for females than for males. The number of deaths by suicide using firearms was higher for males than for females, and substantially varied by country and region. The countries with the highest age-standardised rate of suicides attributable to firearms in 2021 were the USA, Uruguay, and Venezuela. Interpretation Deaths from suicide remain variable by age and sex and across geographical locations, although population mortality rates have continued to improve globally since the 1990s. This study presents, for the first time in GBD, a quantification of the mean age at the time of suicide death, alongside comprehensive estimates of the burden of suicide throughout the world. These analyses will help guide future approaches to reduce suicide mortality that consider a public health framework for prevention. Funding Bill & Melinda Gates Foundation.

Postmortem biochemistry is a valuable tool in forensic investigations, providing insights into the tissue damage and organ dysfunction associated with death. This study aimed to identify biochemical markers that distinguish primary and secondary hypothermia. Twenty-one Wistar rats were allocated into three groups: the Control group (n = 7), which was exposed only to hypothermic conditions, the Alcohol + Hypothermia group (n = 7), and the Benzodiazepines + Hypothermia group (n = 7). The temperature metrics assessed included the normal core temperature, the post-ketamine (0.3 ml injection) core temperature, the immersion temperature, temperature at the onset of hypothermia, and temperature at death. Blood samples were collected from the thoracic aorta in EDTA vacuum tubes for biochemical analysis. The key biochemical parameters measured included the Total Protein (g/L), Albumin (g/L), Globulin (g/L), Albumin to Globulin Ratio, Alanine Aminotransferase (U/L), Alkaline Phosphatase (U/L), Cholesterol (mmol/L), Amylase (U/L), and Lipase (U/L), using an automated IDEXX (Netherlands) cell counter. Significant between-group differences were found for the total protein and globulin levels (p < 0.001 and p = 0.002, respectively), with post-hoc tests confirming differences between the alcohol and control, and benzodiazepine and control groups. The cholesterol levels were found to be significantly different through an omnibus test (p = 0.03), but post hoc tests did not confirm these differences on a statistically significant level. The amylase levels varied significantly across all groups (p < 0.001), with post hoc tests confirming significant differences among all pairs: alcohol vs. benzodiazepine (p = 0.002), alcohol vs. control (p = 0.003), and benzodiazepine vs. control (p < 0.001). The lipase levels showed significant differences in the omnibus test (p = 0.030), but there was no significance in the post hoc tests. Amylase emerged as the most significant parameter in our study, with reduced levels strongly associated with secondary hypothermia. These findings highlight the potential use of total protein, globulin, and amylase levels as biomarkers to differentiate between primary and secondary hypothermia in forensic contexts.

Microscopic signs indicative of drowning are not specific to drowning but also to any other form of suffocation where mechanical obstruction is involved. Our study aimed to evaluate both macroscopic and microscopic findings across different groups sharing a common mechanism of death but differing causes and to compare the diatom test with pathohistological examination.Twenty-nine adult Wistar rats, weighing within recommended ranges, were divided into four groups (L1-L4). The diatom test followed established guidelines for diatoms in water from the Bosna River. Microscopic examination revealed diatoms in the lungs of rats in L3 and L4 groups. Pathohistological findings showed varying degrees of changes including consolidation and inflammatory cell infiltration, dominated by lymphocytes and macrophages, with some samples also showing eosinophilic leukocytes.Significant differences were observed between animals whose cause of death was mechanical asphyxia (suffocatio) and those that were submersed for1 hour versus those that were submersed for 72 hours after death. Diatoms identified in group L4 samples 3, 4, and 5 included Navicula sp. (U3 and U6) and Ulnaria ulna (U4).Our findings suggest combining the diatom test with pathohistological analysis to support a drowning diagnosis. Further examination of other organs could enhance result reliability.

Summary Background Stillbirth is a devastating and often avoidable adverse pregnancy outcome. Monitoring stillbirth levels and trends—in a comprehensive manner that leaves no one uncounted—is imperative for continuing progress in pregnancy loss reduction. This analysis, completed as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, methodically accounted for different stillbirth definitions with the aim of comprehensively estimating all stillbirths at 20 weeks or longer for 204 countries and territories from 1990 to 2021. Methods We extracted data on stillbirths from 11 412 sources across 185 of 204 countries and territories, including 234 surveys, 231 published studies, 1633 vital statistics reports, and 10 585 unique location-year combinations from vital registration systems. Our final dataset comprised 11 different definitions, which were adjusted to match two gestational age thresholds: 20 weeks or longer (reference) and 28 weeks or longer (for comparisons). We modelled the ratio of stillbirth rate to neonatal mortality rate with spatiotemporal Gaussian process regression for each location and year, and then used final GBD 2021 assessments of fertility and all-cause neonatal mortality to calculate total stillbirths. Secondary analyses evaluated the number of stillbirths missed with the more restrictive gestational age definition, trends in stillbirths as a function of Socio-demographic Index, and progress in reducing stillbirths relative to neonatal deaths. Findings In 2021, the global stillbirth rate was 23·0 (95% uncertainty interval [UI] 19·7–27·2) per 1000 births (stillbirths plus livebirths) at 20 weeks' gestation or longer, compared to 16·1 (13·9–19·0) per 1000 births at 28 weeks' gestation or longer. The global neonatal mortality rate in 2021 was 17·1 (14·8–19·9) per 1000 livebirths, corresponding to 2·19 million (1·90–2·55) neonatal deaths. The estimated number of stillbirths occurring at 20 weeks' gestation or longer decreased from 5·08 million (95% UI 4·07–6·35) in 1990 to 3·04 million (2·61–3·62) in 2021, corresponding to a 39·8% (31·8–48·0) reduction, which lagged behind a global improvement in neonatal deaths of 45·6% (36·3–53·1) for the same period (down from 4·03 million [3·86–4·22] neonatal deaths in 1990). Stillbirths in south Asia and sub-Saharan Africa comprised 77·4% (2·35 million of 3·04 million) of the global total, an increase from 60·3% (3·07 million of 5·08 million) in 1990. In 2021, 0·926 million (0·792–1·10) stillbirths, corresponding to 30·5% of the global total (3·04 million), occurred between 20 weeks' gestation and 28 weeks' gestation, with substantial variation at the country level. Interpretation Despite the gradual global decline in stillbirths between 1990 and 2021, the overall number of stillbirths remains substantially high. Counting all stillbirths is paramount to progress, as nearly a third—close to 1 million in total—are left uncounted at the 28 weeks or longer threshold. Our findings draw attention to the differential progress in reducing stillbirths, with a high burden concentrated in countries with low development status. Scarce data availability and poor data quality constrain our capacity to precisely account for stillbirths in many locations. Addressing inequities in universal maternal health coverage, strengthening the quality of maternal health care, and improving the robustness of data systems are urgently needed to reduce the global burden of stillbirths. Funding Bill & Melinda Gates Foundation.

Background: There is no specified diagnostic procedure that can help in determining the cause of death and the diagnosis of drowning because the pathohistological signs are almost identical and non-specified. Aim: Our study aims to recognize and prove diatom appearance in organs from a forensic aspect in Bosnia and Herzegovina, and to examine which is the more specific method in the diagnosis of drowning, the diatom test or the pathohistological finding. Methods: Rats of the recommended body weight were divided into four groups: G1 (n = 8; mechanism of death—asphyxia; cause of death—suffocation, submerged 1 hour after death); G2 (n = 8: mechanism of death-asphyxia; cause of death-suffocation, immersed 72 hours after death); G3 (n = 8: mechanism of death-asphyxia; cause of death-drowning, autopsy immediately after death), and G4 (n = 8: mechanism of death-asphyxia; cause of death-drowning, post mortem 24 hours after death). Results: During the diatom analysis, four species of diatoms, Diatoma vulgaris, Melosira varians, Epithemia adnata, and Cymbella sp, were successfully recovered from the stomach. Microscopic analysis did not detect diatoms in the kidneys and brains of rats, while the pathohistological changes were relatively uniform. Conclusion: Our results propose that the diatom test is a sustainable tool for supporting the diagnosis of drowning in the forensic pathology analysis of the cause of death. This experimental study is a starting point toward the optimization of tests and sampling in cases of unexplained etiology.

Summary Background Up-to-date estimates of stroke burden and attributable risks and their trends at global, regional, and national levels are essential for evidence-based health care, prevention, and resource allocation planning. We aimed to provide such estimates for the period 1990–2021. Methods We estimated incidence, prevalence, death, and disability-adjusted life-year (DALY) counts and age-standardised rates per 100 000 people per year for overall stroke, ischaemic stroke, intracerebral haemorrhage, and subarachnoid haemorrhage, for 204 countries and territories from 1990 to 2021. We also calculated burden of stroke attributable to 23 risk factors and six risk clusters (air pollution, tobacco smoking, behavioural, dietary, environmental, and metabolic risks) at the global and regional levels (21 GBD regions and Socio-demographic Index [SDI] quintiles), using the standard GBD methodology. 95% uncertainty intervals (UIs) for each individual future estimate were derived from the 2·5th and 97·5th percentiles of distributions generated from propagating 500 draws through the multistage computational pipeline. Findings In 2021, stroke was the third most common GBD level 3 cause of death (7·3 million [95% UI 6·6–7·8] deaths; 10·7% [9·8–11·3] of all deaths) after ischaemic heart disease and COVID-19, and the fourth most common cause of DALYs (160·5 million [147·8–171·6] DALYs; 5·6% [5·0–6·1] of all DALYs). In 2021, there were 93·8 million (89·0–99·3) prevalent and 11·9 million (10·7–13·2) incident strokes. We found disparities in stroke burden and risk factors by GBD region, country or territory, and SDI, as well as a stagnation in the reduction of incidence from 2015 onwards, and even some increases in the stroke incidence, death, prevalence, and DALY rates in southeast Asia, east Asia, and Oceania, countries with lower SDI, and people younger than 70 years. Globally, ischaemic stroke constituted 65·3% (62·4–67·7), intracerebral haemorrhage constituted 28·8% (28·3–28·8), and subarachnoid haemorrhage constituted 5·8% (5·7–6·0) of incident strokes. There were substantial increases in DALYs attributable to high BMI (88·2% [53·4–117·7]), high ambient temperature (72·4% [51·1 to 179·5]), high fasting plasma glucose (32·1% [26·7–38·1]), diet high in sugar-sweetened beverages (23·4% [12·7–35·7]), low physical activity (11·3% [1·8–34·9]), high systolic blood pressure (6·7% [2·5–11·6]), lead exposure (6·5% [4·5–11·2]), and diet low in omega-6 polyunsaturated fatty acids (5·3% [0·5–10·5]). Interpretation Stroke burden has increased from 1990 to 2021, and the contribution of several risk factors has also increased. Effective, accessible, and affordable measures to improve stroke surveillance, prevention (with the emphasis on blood pressure, lifestyle, and environmental factors), acute care, and rehabilitation need to be urgently implemented across all countries to reduce stroke burden. Funding Bill & Melinda Gates Foundation.

Background - Organ donation and organ transplantation refer to a medical treatment approach that involves substituting a diseased or damaged organ or tissue in the human body with a healthy one. Progress in surgical techniques, immunology, and medical science has facilitated the advancement of transplant procedures. Nowadays, a wide range of organs, organ parts, and tissues can be successfully transplanted. Depending on the part of the body in question, the organs that are donated can come from a deceased donor or from a living person. Factors that influence the individual in a positive direction in terms of donating their organs have been presented in previous studies as the socio-economic status of informants, education level, being young, gender, donation to family members and social support. Aim - of this study is to synthesize qualitative and quantitative research on individuals' attitudes and decisions regarding organ donation, as well as the factors influencing these matters. Materials and Methods - A systematic search was conducted on the PubMed, Embase, CINAHL, and Web of Science databases for qualitative and quantitative literature regarding factors influencing an individual to donate their organs to other individuals. An inductive thematic analysis was conducted to generate themes and supporting subthemes. Fifteen studies were included. Results - The three main themes were: socioeconomic and cultural factors, dissatisfaction with, and mistrust of the healthcare system. Unspecified donors demonstrated a deep sense of different factors that influenced the individual to donate their organs to other individuals. Religious factors, fear and prejudices, gender differences, the influence of family members and not being treated well by healthcare professionals were only a few of the factors that were stated in the present study. Conclusion - The results of the present study show that there were many different factors that influenced an individual to decide whether to donate organs. Even though the individuals belong to different religions, come from different cultures, look at family relationships differently and have different degrees of knowledge, the opinions and factors that influence their decision regarding organ donation are the same. Healthcare should work more actively to inform and increase knowledge and consciousness about organ donation among people who are prospective donors. This can mean more information in several different languages, as well as where different religions stand on organ donation. Key words: Organ donation, transplantation, influence, factors, decision, review.

Objective The aim was to test the Belgrade age formula based on the calculation of open apices of two permanent mandibular teeth on a Bosnian children population and compare its accuracy with European formula. Material and methods We included 412 panoramic images of children (204 female and 208 male) 7 to 13 years of age. We assessed the performance of both methods (the European formula and the BAF) and compared their results in both sexes. Results The results showed a high point of average understanding between the age estimated by chronological age and the European formula (ICC=0.927, 95% CI 0.904–0.944, p<0.001)., BAF also confirmed a high point of agreement with chronological age in boys (ICC=0.941, 95% CI 0.922–0.955, p<0.001) and girls (ICC=0.913, 95% CI 0.886–0.934, p<0.001). BAF was better than the European formula in estimating age in males (0.4448±0.9135 vs. 0.9807±0.9422). Conclusion The Belgrade Age Formula (BAF) demonstrates comparable accuracy to the European formula for age determination in Bosnian children, while offering the advantage of being easier and faster to use. This makes the BAF a practical alternative in clinical and research settings where efficiency and reliability are essential.

INTRODUCTION Hypothermia is defined as a body core temperature below 35 °C and can be caused by internal or external stress. Primary hypothermia is caused by excessive exposure to low environmental temperature without any medical conditions prior to that. Secondary hypothermia is caused by alteration in thermoregulation by disease, trauma, surgery, drugs, or infections. The aim of the research is to investigate core temperature values in rats subjected to specific water temperatures at five different time points. It focuses on distinguishing between primary and secondary hypothermia in these rats. METHODS The total 21 Wistar rats were divided into three experimental groups as: Control group rats exposed only to hypothermic condition (n = 7); Alcohol + hypothermia (n = 7); and Benzodiazepines + hypothermia (n = 7). The temperature spots analyzed in the study were: normal core temperature, core temperature during injection of 0,3 ketamine, temperature of immersion and the temperature at the onset of hypothermia and temperature at the time of death. RESULTS In our study the comparative analysis of body temperatures at various time points following submersion in water revealed significant differences among the study groups treated with either alcohol or benzodiazepines and the control group. Notable differences were observed in baseline temperature, post-anesthesia induction temperature, and immediate post-submersion temperature. Specifically, significant differences were discovered among the alcohol and benzodiazepine groups (p < 0.001) and ranging from the alcohol and control groups (p < 0.001). The analysis of survival times following induced hypothermia revealed a statistically significant difference among the three experimental groups (p = 0.04), though subsequent post-hoc comparisons did not demonstrate significant differences in mean survival times. CONCLUSION There is a difference in survival time between primary and secondary hypothermia groups, depending on consumption and intoxication with alcohol or benzodiazepines. The analysis of survival times following induced hypothermia showed a statistically significant difference among the groups.

INTRODUCTION Cutaneous leishmaniasis (CL) is one of the neglected tropical diseases that affects impoverished communities throughout the world. In Pakistan CL is an endemic disease. AIMS AND OBJECTIVES This study aimed to determine the incidence of CL infection in the Baluchistan province of Pakistan from January 2020 to March 2022 during the COVID-19 pandemic. METHODOLOGY A total of 1047 clinically suspected cases of CL from Bolan Medical College Hospital, Quetta, were followed up in the study. The data regarding the epidemiological characterstics, pathological information, and treatment of patients was collected. RESULTS Out of 1047 probable cases of CL, 594 (56.73%) cases were found to be positive for CL. Females had the highest infection rate, with the majority of reported cases being in the 0-9-year age group. Most CL cases were reported in April in the year 2020, with a few cases reported in June. But in the year 2021, the highest number of cases were reported in December. The number of overall cases has gradually increased in the year 2022, most likely because of the reduction in COVID-19 pandemic restrictions. The p value for the positive as compared to suspected cases in the years 2020, 2021, and 2022 was calculated as 0.8925, 0.8763, and 0.8535 respectively. CONCLUSIONS Further epidemiological studies and health education campaigns are recommended to increase public awareness. It is strongly advised that local, provincial, and national health authorities establish and maintain effective leishmaniasis surveillance systems to promptly identify disease outbreaks and implement timely control measures.

Aim To investigate how immigrants from the Balkan region experienced their current life situation after living in Sweden for 30 years or more. Materials The study was designed as a qualitative study using data from interviews with informants from five Balkan countries. The inclusion criteria were informants who were immigrants to Sweden and had lived in Sweden for more than 30 years. Five groups comprising sixteen informants were invited to participate in the study, and they all agreed. Results The analysis of the interviews resulted in three main categories: "from someone to no one", "labour market", and "discrimination". All the informants reported that having an education and life experience was worth-less, having a life but having to start over, re-educating, applying for many jobs but often not being answered, and finally getting a job for which every in-formant was educated but being humiliated every day and treated separately as well as being discriminated against. Conclusion Coming to Sweden with all their problems, having an education and work experience that was equal to zero in Sweden, studying Swedish and re-reading/repeating all their education, looking for a job and not receiving answers to applications, and finally getting a job but being treated differently and discriminated against on a daily basis was experienced by all the in-formants as terrible. Even though there are enough similar studies in Sweden, it is always good to write more to help prospective immigrants and prospective employers in Sweden.

Summary Background Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions. Funding Bill & Melinda Gates Foundation.

Summary Background Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. Methods The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model—a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates—with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality—which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. Findings The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2–100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1–290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1–211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4–48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3–37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7–9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. Interpretation Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. Funding Bill & Melinda Gates Foundation.