210 research outputs found
Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950โ2019 : a comprehensive demographic analysis for the Global Burden of Disease Study 2019
Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10โ14 and 50โ54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. The global TFR decreased from 2ยท72 (95% uncertainty interval [UI] 2ยท66โ2ยท79) in 2000 to 2ยท31 (2ยท17โ2ยท46) in 2019. Global annual livebirths increased from 134ยท5 million (131ยท5โ137ยท8) in 2000 to a peak of 139ยท6 million (133ยท0โ146ยท9) in 2016. Global livebirths then declined to 135ยท3 million (127ยท2โ144ยท1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2ยท1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27ยท1% (95% UI 26ยท4โ27ยท8) of global livebirths. Global life expectancy at birth increased from 67ยท2 years (95% UI 66ยท8โ67ยท6) in 2000 to 73ยท5 years (72ยท8โ74ยท3) in 2019. The total number of deaths increased from 50ยท7 million (49ยท5โ51ยท9) in 2000 to 56ยท5 million (53ยท7โ59ยท2) in 2019. Under-5 deaths declined from 9ยท6 million (9ยท1โ10ยท3) in 2000 to 5ยท0 million (4ยท3โ6ยท0) in 2019. Global population increased by 25ยท7%, from 6ยท2 billion (6ยท0โ6ยท3) in 2000 to 7ยท7 billion (7ยท5โ8ยท0) in 2019. In 2019, 34 countries had negative natural rates of increase in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58ยท6 years (56ยท1โ60ยท8) in 2000 to 63ยท5 years (60ยท8โ66ยท1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. Over the past 20 years, fertility rates have been dropping steadily and life expectancy has been increasing, with few exceptions. Much of this change follows historical patterns linking social and economic determinants, such as those captured by the GBD Socio-demographic Index, with demographic outcomes. More recently, several countries have experienced a combination of low fertility and stagnating improvement in mortality rates, pushing more populations into the late stages of the demographic transition. Tracking demographic change and the emergence of new patterns will be essential for global health monitoring. Bill & Melinda Gates Foundation. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate โMuhammad Aziz Rahmanโ is provided in this record*
DESIGN AND FABRICATION OF COMBINED ELECTROMAGNETIC AND MAGNETIC DRUM-BELT CONVEYOR SEPARATOR
Mineral processing operations are faced with many challenges which include effective separation of unwanted materials generated through the extraction process from the bulk material. Magnetic device is a machine used for separating magnetic materials from non-magnetic materials by inducing the magnetic flux. Magnetic and electromagnetic separators are widely used as primary separation equipment. This work was centred on the design and construction of a laboratory-sized dual purpose magnetic and electromagnetic separator for separating the magnetic particles from the rest of the bulk mineral or ferrous materials from foundry sand in a single system. The main components of the equipment include: the hopper, conveyor belt rotating drums, pulley and belt, electromagnet. The approaches to achieving the result reported include the design conceptualization, design calculation, design drawing using the AutoCAD and Inventor software, fabrication and assembly of components. The evaluation showed that electromagnetic separation is more efficient than magnetic separation. The equipment was fabricated at an average cost of 224,000:00 naira
Prevalence and Prognostic Features of ECG Abnormalities in Acute Stroke: Findings From the SIREN Study Among Africans
Background
Africa has a growing burden of stroke with associated high morbidity and a 3-year fatality rate of 84%. Cardiac disease contributes to stroke occurrence and outcomes, but the precise relationship of abnormalities as noted on a cheap and widely available test, the electrocardiogram (ECG), and acute stroke outcomes have not been previously characterized in Africans.
Objectives
The study assessed the prevalence and prognoses of various ECG abnormalities among African acute stroke patients encountered in a multisite, cross-national epidemiologic study.
Methods
We included 890 patients from Nigeria and Ghana with acute stroke who had 12-lead ECG recording within first 24 h of admission and stroke classified based on brain computed tomography scan or magnetic resonance imaging. Stroke severity at baseline was assessed using the Stroke Levity Scale (SLS), whereas 1-month outcome was assessed using the modified Rankin Scale (mRS).
Results Patients\u27 mean age was 58.4 ยฑ 13.4 years, 490 were men (55%) and 400 were women (45%), 65.5% had ischemic stroke, and 85.4% had at least 1 ECG abnormality. Women were significantly more likely to have atrial fibrillation, or left ventricular hypertrophy with or without strain pattern. Compared to ischemic stroke patients, hemorrhagic stroke patients were less likely to have atrial fibrillation (1.0% vs. 6.7%; p = 0.002), but more likely to have left ventricular hypertrophy (64.4% vs. 51.4%; p = 0.004). Odds of severe disability or death at 1 month were higher with severe stroke (AOR: 2.25; 95% confidence interval: 1.44 to 3.50), or atrial enlargement (AOR: 1.45; 95% confidence interval: 1.04 to 2.02).
Conclusions
About 4 in 5 acute stroke patients in this African cohort had evidence of a baseline ECG abnormality, but presence of any atrial enlargement was the only independent ECG predictor of death or disability
Exploring Overlaps Between the Genomic and Environmental Determinants of LVH and Stroke: A Multicenter Study in West Africa
Background
Whether left ventricular hypertrophy (LVH) is determined by similar genomic and environmental risk factors with stroke, or is simply an intermediate stroke marker, is unknown.
Objectives
We present a research plan and preliminary findings to explore the overlap in the genomic and environmental determinants of LVH and stroke among Africans participating in the SIREN (Stroke Investigative Research and Education Network) study.
Methods
SIREN is a transnational, multicenter study involving acute stroke patients and age-, ethnicity-, and sex-matched control subjects recruited from 9 sites in Ghana and Nigeria. Genomic and environmental risk factors and other relevant phenotypes for stroke and LVH are being collected and compared using standard techniques.
Results
This preliminary analysis included only 725 stroke patients (mean age 59.1 ยฑ 13.2 years; 54.3% male). Fifty-five percent of the stroke subjects had LVH with greater proportion among women (51.6% vs. 48.4%; p \u3c 0.001). Those with LVH were younger (57.9 ยฑ 12.8 vs. 60.6 ยฑ 13.4; p = 0.006) and had higher mean systolic and diastolic blood pressure (167.1/99.5 mm Hg vs 151.7/90.6 mm Hg; p \u3c 0.001). Uncontrolled blood pressure at presentation was prevalent in subjects with LVH (76.2% vs. 57.7%; p \u3c 0.001). Significant independent predictors of LVH were age \u3c45 years (adjusted odds ratio [AOR]: 1.91; 95% confidence interval [CI]: 1.14 to 3.19), female sex (AOR: 2.01; 95% CI: 1.44 to 2.81), and diastolic blood pressure \u3e 90 mm Hg (AOR: 2.10; 95% CI: 1.39 to 3.19; p \u3c 0.001).
Conclusions
The prevalence of LVH was high among stroke patients especially the younger ones, suggesting a genetic component to LVH. Hypertension was a major modifiable risk factor for stroke as well as LVH. It is envisaged that the SIREN project will elucidate polygenic overlap (if present) between LVH and stroke among Africans, thereby defining the role of LVH as a putative intermediate cardiovascular phenotype and therapeutic target to inform interventions to reduce stroke risk in populations of African ancestry
Global, regional, and national age-sex-specific mortality for 282 causes of death in 195 countries and territories, 1980โ2017: A systematic analysis for the Global Burden of Disease Study 2017
Background Global development goals increasingly rely on country-specific estimates for benchmarking a nation's progress. To meet this need, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 estimated global, regional, national, and, for selected locations, subnational cause-specific mortality beginning in the year 1980. Here we report an update to that study, making use of newly available data and improved methods. GBD 2017 provides a comprehensive assessment of cause-specific mortality for 282 causes in 195 countries and territories from 1980 to 2017. Methods The causes of death database is composed of vital registration (VR), verbal autopsy (VA), registry, survey, police, and surveillance data. GBD 2017 added ten VA studies, 127 country-years of VR data, 502 cancer-registry country-years, and an additional surveillance country-year. Expansions of the GBD cause of death hierarchy resulted in 18 additional causes estimated for GBD 2017. Newly available data led to subnational estimates for five additional countriesโEthiopia, Iran, New Zealand, Norway, and Russia. Deaths assigned International Classification of Diseases (ICD) codes for non-specific, implausible, or intermediate causes of death were reassigned to underlying causes by redistribution algorithms that were incorporated into uncertainty estimation. We used statistical modelling tools developed for GBD, including the Cause of Death Ensemble model (CODEm), to generate cause fractions and cause-specific death rates for each location, year, age, and sex. Instead of using UN estimates as in previous versions, GBD 2017 independently estimated population size and fertility rate for all locations. Years of life lost (YLLs) were then calculated as the sum of each death multiplied by the standard life expectancy at each age. All rates reported here are age-standardised. Findings At the broadest grouping of causes of death (Level 1), non-communicable diseases (NCDs) comprised the greatest fraction of deaths, contributing to 73ยท4% (95% uncertainty interval [UI] 72ยท5โ74ยท1) of total deaths in 2017, while communicable, maternal, neonatal, and nutritional (CMNN) causes accounted for 18ยท6% (17ยท9โ19ยท6), and injuries 8ยท0% (7ยท7โ8ยท2). Total numbers of deaths from NCD causes increased from 2007 to 2017 by 22ยท7% (21ยท5โ23ยท9), representing an additional 7ยท61 million (7ยท20โ8ยท01) deaths estimated in 2017 versus 2007. The death rate from NCDs decreased globally by 7ยท9% (7ยท0โ8ยท8). The number of deaths for CMNN causes decreased by 22ยท2% (20ยท0โ24ยท0) and the death rate by 31ยท8% (30ยท1โ33ยท3). Total deaths from injuries increased by 2ยท3% (0ยท5โ4ยท0) between 2007 and 2017, and the death rate from injuries decreased by 13ยท7% (12ยท2โ15ยท1) to 57ยท9 deaths (55ยท9โ59ยท2) per 100โ000 in 2017. Deaths from substance use disorders also increased, rising from 284โ000 deaths (268โ000โ289โ000) globally in 2007 to 352โ000 (334โ000โ363โ000) in 2017. Between 2007 and 2017, total deaths from conflict and terrorism increased by 118ยท0% (88ยท8โ148ยท6). A greater reduction in total deaths and death rates was observed for some CMNN causes among children younger than 5 years than for older adults, such as a 36ยท4% (32ยท2โ40ยท6) reduction in deaths from lower respiratory infections for children younger than 5 years compared with a 33ยท6% (31ยท2โ36ยท1) increase in adults older than 70 years. Globally, the number of deaths was greater for men than for women at most ages in 2017, except at ages older than 85 years. Trends in global YLLs reflect an epidemiological transition, with decreases in total YLLs from enteric infections, respiratory infections and tuberculosis, and maternal and neonatal disorders between 1990 and 2017; these were generally greater in magnitude at the lowest levels of the Socio-demographic Index (SDI). At the same time, there were large increases in YLLs from neoplasms and cardiovascular diseases. YLL rates decreased across the five leading Level 2 causes in all SDI quintiles. The leading causes of YLLs in 1990โneonatal disorders, lower respiratory infections, and diarrhoeal diseasesโwere ranked second, fourth, and fifth, in 2017. Meanwhile, estimated YLLs increased for ischaemic heart disease (ranked first in 2017) and stroke (ranked third), even though YLL rates decreased. Population growth contributed to increased total deaths across the 20 leading Level 2 causes of mortality between 2007 and 2017. Decreases in the cause-specific mortality rate reduced the effect of population growth for all but three causes: substance use disorders, neurological disorders, and skin and subcutaneous diseases. Interpretation Improvements in global health have been unevenly distributed among populations. Deaths due to injuries, substance use disorders, armed conflict and terrorism, neoplasms, and cardiovascular disease are expanding threats to global health. For causes of death such as lower respiratory and enteric infections, more rapid progress occurred for children than for the oldest adults, and there is continuing disparity in mortality rates by sex across age groups. Reductions in the death rate of some common diseases are themselves slowing or have ceased, primarily for NCDs, and the death rate for selected causes has increased in the past decade. Funding Bill & Melinda Gates Foundation
Global, regional, and national age-sex-specific mortality and life expectancy, 1950โ2017: A systematic analysis for the Global Burden of Disease Study 2017
Background Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. Methods The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. Findings Globally, 18ยท7% (95% uncertainty interval 18ยท4โ19ยท0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58ยท8% (58ยท2โ59ยท3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48ยท1 years (46ยท5โ49ยท6) to 70ยท5 years (70ยท1โ70ยท8) for men and from 52ยท9 years (51ยท7โ54ยท0) to 75ยท6 years (75ยท3โ75ยท9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49ยท1 years (46ยท5โ51ยท7) for men in the Central African Republic to 87ยท6 years (86ยท9โ88ยท1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216ยท0 deaths (196ยท3โ238ยท1) per 1000 livebirths in 1950 to 38ยท9 deaths (35ยท6โ42ยท83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5ยท4 million (5ยท2โ5ยท6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. Interpretation This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing. Funding Bill & Melinda Gates Foundation
Global, regional, and national disability-adjusted life-years (DALYs) for 359 diseases and injuries and healthy life expectancy (HALE) for 195 countries and territories, 1990โ2017: A systematic analysis for the Global Burden of Disease Study 2017
Background How long one lives, how many years of life are spent in good and poor health, and how the population's state of health and leading causes of disability change over time all have implications for policy, planning, and provision of services. We comparatively assessed the patterns and trends of healthy life expectancy (HALE), which quantifies the number of years of life expected to be lived in good health, and the complementary measure of disability-adjusted life-years (DALYs), a composite measure of disease burden capturing both premature mortality and prevalence and severity of ill health, for 359 diseases and injuries for 195 countries and territories over the past 28 years. Methods We used data for age-specific mortality rates, years of life lost (YLLs) due to premature mortality, and years lived with disability (YLDs) from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 to calculate HALE and DALYs from 1990 to 2017. We calculated HALE using age-specific mortality rates and YLDs per capita for each location, age, sex, and year. We calculated DALYs for 359 causes as the sum of YLLs and YLDs. We assessed how observed HALE and DALYs differed by country and sex from expected trends based on Socio-demographic Index (SDI). We also analysed HALE by decomposing years of life gained into years spent in good health and in poor health, between 1990 and 2017, and extra years lived by females compared with males. Findings Globally, from 1990 to 2017, life expectancy at birth increased by 7ยท4 years (95% uncertainty interval 7ยท1โ7ยท8), from 65ยท6 years (65ยท3โ65ยท8) in 1990 to 73ยท0 years (72ยท7โ73ยท3) in 2017. The increase in years of life varied from 5ยท1 years (5ยท0โ5ยท3) in high SDI countries to 12ยท0 years (11ยท3โ12ยท8) in low SDI countries. Of the additional years of life expected at birth, 26ยท3% (20ยท1โ33ยท1) were expected to be spent in poor health in high SDI countries compared with 11ยท7% (8ยท8โ15ยท1) in low-middle SDI countries. HALE at birth increased by 6ยท3 years (5ยท9โ6ยท7), from 57ยท0 years (54ยท6โ59ยท1) in 1990 to 63ยท3 years (60ยท5โ65ยท7) in 2017. The increase varied from 3ยท8 years (3ยท4โ4ยท1) in high SDI countries to 10ยท5 years (9ยท8โ11ยท2) in low SDI countries. Even larger variations in HALE than these were observed between countries, ranging from 1ยท0 year (0ยท4โ1ยท7) in Saint Vincent and the Grenadines (62ยท4 years [59ยท9โ64ยท7] in 1990 to 63ยท5 years [60ยท9โ65ยท8] in 2017) to 23ยท7 years (21ยท9โ25ยท6) in Eritrea (30ยท7 years [28ยท9โ32ยท2] in 1990 to 54ยท4 years [51ยท5โ57ยท1] in 2017). In most countries, the increase in HALE was smaller than the increase in overall life expectancy, indicating more years lived in poor health. In 180 of 195 countries and territories, females were expected to live longer than males in 2017, with extra years lived varying from 1ยท4 years (0ยท6โ2ยท3) in Algeria to 11ยท9 years (10ยท9โ12ยท9) in Ukraine. Of the extra years gained, the proportion spent in poor health varied largely across countries, with less than 20% of additional years spent in poor health in Bosnia and Herzegovina, Burundi, and Slovakia, whereas in Bahrain all the extra years were spent in poor health. In 2017, the highest estimate of HALE at birth was in Singapore for both females (75ยท8 years [72ยท4โ78ยท7]) and males (72ยท6 years [69ยท8โ75ยท0]) and the lowest estimates were in Central African Republic (47ยท0 years [43ยท7โ50ยท2] for females and 42ยท8 years [40ยท1โ45ยท6] for males). Globally, in 2017, the five leading causes of DALYs were neonatal disorders, ischaemic heart disease, stroke, lower respiratory infections, and chronic obstructive pulmonary disease. Between 1990 and 2017, age-standardised DALY rates decreased by 41ยท3% (38ยท8โ43ยท5) for communicable diseases and by 49ยท8% (47ยท9โ51ยท6) for neonatal disorders. For non-communicable diseases, global DALYs increased by 40ยท1% (36ยท8โ43ยท0), although age-standardised DALY rates decreased by 18ยท1% (16ยท0โ20ยท2). Interpretation With increasing life expectancy in most countries, the question of whether the additional years of life gained are spent in good health or poor health has been increasingly relevant because of the potential policy implications, such as health-care provisions and extending retirement ages. In some locations, a large proportion of those additional years are spent in poor health. Large inequalities in HALE and disease burden exist across countries in different SDI quintiles and between sexes. The burden of disabling conditions has serious implications for health system planning and health-related expenditures. Despite the progress made in reducing the burden of communicable diseases and neonatal disorders in low SDI countries, the speed of this progress could be increased by scaling up proven interventions. The global trends among non-communicable diseases indicate that more effort is needed to maximise HALE, such as risk prevention and attention to upstream determinants of health. Funding Bill & Melinda Gates Foundation
Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018
Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000โ2018 geospatial estimates of anemia prevalence in women of reproductive age (15โ49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organizationโs Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations
Global, regional, and national burden of chronic kidney disease, 1990โ2017 : a systematic analysis for the Global Burden of Disease Study 2017
Background
Health system planning requires careful assessment of chronic kidney disease (CKD) epidemiology, but data for morbidity and mortality of this disease are scarce or non-existent in many countries. We estimated the global, regional, and national burden of CKD, as well as the burden of cardiovascular disease and gout attributable to impaired kidney function, for the Global Burden of Diseases, Injuries, and Risk Factors Study 2017. We use the term CKD to refer to the morbidity and mortality that can be directly attributed to all stages of CKD, and we use the term impaired kidney function to refer to the additional risk of CKD from cardiovascular disease and gout.
Methods
The main data sources we used were published literature, vital registration systems, end-stage kidney disease registries, and household surveys. Estimates of CKD burden were produced using a Cause of Death Ensemble model and a Bayesian meta-regression analytical tool, and included incidence, prevalence, years lived with disability, mortality, years of life lost, and disability-adjusted life-years (DALYs). A comparative risk assessment approach was used to estimate the proportion of cardiovascular diseases and gout burden attributable to impaired kidney function.
Findings
Globally, in 2017, 1ยท2 million (95% uncertainty interval [UI] 1ยท2 to 1ยท3) people died from CKD. The global all-age mortality rate from CKD increased 41ยท5% (95% UI 35ยท2 to 46ยท5) between 1990 and 2017, although there was no significant change in the age-standardised mortality rate (2ยท8%, โ1ยท5 to 6ยท3). In 2017, 697ยท5 million (95% UI 649ยท2 to 752ยท0) cases of all-stage CKD were recorded, for a global prevalence of 9ยท1% (8ยท5 to 9ยท8). The global all-age prevalence of CKD increased 29ยท3% (95% UI 26ยท4 to 32ยท6) since 1990, whereas the age-standardised prevalence remained stable (1ยท2%, โ1ยท1 to 3ยท5). CKD resulted in 35ยท8 million (95% UI 33ยท7 to 38ยท0) DALYs in 2017, with diabetic nephropathy accounting for almost a third of DALYs. Most of the burden of CKD was concentrated in the three lowest quintiles of Socio-demographic Index (SDI). In several regions, particularly Oceania, sub-Saharan Africa, and Latin America, the burden of CKD was much higher than expected for the level of development, whereas the disease burden in western, eastern, and central sub-Saharan Africa, east Asia, south Asia, central and eastern Europe, Australasia, and western Europe was lower than expected. 1ยท4 million (95% UI 1ยท2 to 1ยท6) cardiovascular disease-related deaths and 25ยท3 million (22ยท2 to 28ยท9) cardiovascular disease DALYs were attributable to impaired kidney function.
Interpretation
Kidney disease has a major effect on global health, both as a direct cause of global morbidity and mortality and as an important risk factor for cardiovascular disease. CKD is largely preventable and treatable and deserves greater attention in global health policy decision making, particularly in locations with low and middle SDI
Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950โ2021, and the impact of the COVID-19 pandemic:a comprehensive demographic analysis for the Global Burden of Disease Study 2021
Background Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020โ21 COVID-19 pandemic period. Methods 22โ223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30โ763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31โ642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62ยท8% [95% UI 60ยท5โ65ยท1] decline), and increased during the COVID-19 pandemic period (2020โ21; 5ยท1% [0ยท9โ9ยท6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4ยท66 million (3ยท98โ5ยท50) global deaths in children younger than 5 years in 2021 compared with 5ยท21 million (4ยท50โ6ยท01) in 2019. An estimated 131 million (126โ137) people died globally from all causes in 2020 and 2021 combined, of which 15ยท9 million (14ยท7โ17ยท2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100โ000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22ยท7 years (20ยท8โ24ยท8), from 49ยท0 years (46ยท7โ51ยท3) to 71ยท7 years (70ยท9โ72ยท5). Global life expectancy at birth declined by 1ยท6 years (1ยท0โ2ยท2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15ยท7%) of 204 countries and territories between 2019 and 2021. The global population reached 7ยท89 billion (7ยท67โ8ยท13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39ยท5% [28ยท4โ52ยท7]) and south Asia (26ยท3% [9ยท0โ44ยท7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92ยท2%) of 204 nations. Interpretation Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic. Funding Bill & Melinda Gates Foundation.<br/
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