Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950–2019: A comprehensive demographic analysis for the Global Burden of Disease Study 2019

Background: 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. Methods: 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 10–14 and 50–54 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. Findings: The global TFR decreased from 2·72 (95% uncertainty interval [UI] 2·66–2·79) in 2000 to 2·31 (2·17–2·46) in 2019. Global annual livebirths increased from 134·5 million (131·5–137·8) in 2000 to a peak of 139·6 million (133·0–146·9) in 2016. Global livebirths then declined to 135·3 million (127·2–144·1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2·1, 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 27·1% (95% UI 26·4–27·8) of global livebirths. Global life expectancy at birth increased from 67·2 years (95% UI 66·8–67·6) in 2000 to 73·5 years (72·8–74·3) in 2019. The total number of deaths increased from 50·7 million (49·5–51·9) in 2000 to 56·5 million (53·7–59·2) in 2019. Under-5 deaths declined from 9·6 million (9·1–10·3) in 2000 to 5·0 million (4·3–6·0) in 2019. Global population increased by 25·7%, from 6·2 billion (6·0–6·3) in 2000 to 7·7 billion (7·5–8·0) 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 58·6 years (56·1–60·8) in 2000 to 63·5 years (60·8–66·1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. Interpretation: 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. Funding: Bill & Melinda Gates Foundation.</p

Mapping routine measles vaccination in low- and middle-income countries

The safe, highly effective measles vaccine has been recommended globally since 1974, yet in 2017 there were more than 17 million cases of measles and 83,400 deaths in children under 5 years old, and more than 99% of both occurred in low- and middle-income countries (LMICs)1,2,3,4. Globally comparable, annual, local estimates of routine first-dose measles-containing vaccine (MCV1) coverage are critical for understanding geographically precise immunity patterns, progress towards the targets of the Global Vaccine Action Plan (GVAP), and high-risk areas amid disruptions to vaccination programmes caused by coronavirus disease 2019 (COVID-19)5,6,7,8. Here we generated annual estimates of routine childhood MCV1 coverage at 5 × 5-km2 pixel and second administrative levels from 2000 to 2019 in 101 LMICs, quantified geographical inequality and assessed vaccination status by geographical remoteness. After widespread MCV1 gains from 2000 to 2010, coverage regressed in more than half of the districts between 2010 and 2019, leaving many LMICs far from the GVAP goal of 80% coverage in all districts by 2019. MCV1 coverage was lower in rural than in urban locations, although a larger proportion of unvaccinated children overall lived in urban locations; strategies to provide essential vaccination services should address both geographical contexts. These results provide a tool for decision-makers to strengthen routine MCV1 immunization programmes and provide equitable disease protection for all children

Diabetes, obesity, hypertension, and risk of severe COVID19: a protocol for systematic review and meta-analysis

Introduction Previous evidence from several countries, including China, Italy, Mexico, UK and the USA, indicates that among patients with confirmed COVID-19 who were hospitalised, diabetes, obesity and hypertension might be important risk factors for severe clinical outcomes. Several preliminary systematic reviews and meta-analyses have been conducted on one or more of these non-communicable diseases, but the findings have not been definitive, and recent evidence has become available from many more populations. Thus, we aim to conduct a systematic review and meta-analysis of observational studies to assess the relationship of diabetes, obesity and hypertension with severe clinical outcomes in patients with COVID-19. Method and analysis We will search 16 major databases (MEDLINE, Embase, Global Health, CAB Abstracts, PsycINFO, CINAHL, Academic Research Complete, Africa Wide Information, Scopus, PubMed Central, ProQuest Central, WHO Virtual Health Library, Homeland Security COVID-19 collection, SciFinder, Clinical Trials and Cochrane Library) for articles published between December 2019 and December 2020. We will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols 2016 guidelines for the design and reporting the results. We will include observational studies that assess the associations of pre-existing diabetes, obesity and hypertension in patients with COVID-19 with risk of severe clinical outcomes such as intensive care unit admission, receiving mechanical ventilation or death. Stata V.16.1 and R-Studio V.1.4.1103 statistical software will be used for statistical analysis. Meta-analysis will be used to estimate the pooled risks and to assess potential heterogeneities in risks. Ethics and dissemination The study was reviewed for human subjects concerns by the US CDC Center for Global Health and determined to not represent human subjects research because it uses data from published studies. We plan to publish results in a peer-reviewed journal and present at national and international conferences. PROSPERO registration number CRD42021204371

Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020

Background The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods For this analysis, we constructed burden-weighted dose–response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15–95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15–39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0–0) and 0·603 (0·400–1·00) standard drinks per day, and the NDE varied between 0·002 (0–0) and 1·75 (0·698–4·30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0·114 (0–0·403) to 1·87 (0·500–3·30) standard drinks per day and an NDE that ranged between 0·193 (0–0·900) and 6·94 (3·40–8·30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59·1% (54·3–65·4) were aged 15–39 years and 76·9% (73·0–81·3) were male. Interpretation There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Funding Bill & Melinda Gates Foundation

Body-mass index, blood pressure and cause-specific mortality in India: Prospective study of 500 000 adults

Background The associations of cause-specific mortality with body-mass index (BMI) have been studied mainly in higher-income countries. We relate BMI and systolic blood pressure (SBP) to mortality in a South Asian population. Methods In 1998-2001, 500,810 men and women (age≥35) in Chennai city were interviewed, measured, then visited biennially from 2015, recording structured narratives of any deaths before 31.3.2015 for physician coding; in 2013-14, 10,161 participants were re-surveyed. After excluding all with missing data or chronic disease at recruitment or who died within 2 years (leaving 414,746 participants), Cox regressions (standardised for tobacco, alcohol and social factors) relate mortality rate ratios at ages 35-69 (RRs) to SBP, BMI, or BMI given usual SBP. Findings Mean SBP and BMI at recruitment were 127 mmHg (SD15) and 23 kg/m2 (SD4): correlations with re-survey measurements 14 years later were, respectively, 50% and 88%. Low BMI was strongly associated with poverty, tobacco, and alcohol. Of 29,519 deaths at ages 35-69, half were vascular (mainly cardiac). Cardiac and stroke mortality increased steeply with SBP: as in Western populations, 20 mmHg higher usual SBP approximately doubled vascular mortality, as did diabetes. But, although BMI strongly affected SBP (~1 mmHg/kg/m2) and diabetes prevalence, BMI was little related to cardiac or other vascular mortality, with only small excesses even at BMI≥30 kg/m2. After additionally allowing for the usual SBP, BMI was inversely related to cardiac and stroke mortality throughout 15-30 kg/m2; comparing under vs overweight (15-18.5 vs 25-30 kg/m2), cardiac mortality RR was 1.29 (95%CI 1.20-1.38) and stroke mortality RR was 1.47 (1.23-1.75). Interpretation In this South Asian population, BMI was little associated with vascular mortality, even though BMI increases SBP and SBP increases vascular mortality. Hence, there must be importantly adverse effects of some close correlates of below-average BMI, which could be of relevance in all populations.</p

Body-mass index, blood pressure, diabetes and cardiovascular mortality in Cuba: prospective cohort study of 146,665 participants

Background Cardiovascular disease (CVD) is a leading cause of premature death in Cuba, accounting for about one third of all deaths under age 70 years. Substantial uncertainty remains, however, about the relevance of major metabolic risk factors to CVD mortality in this population. Purpose To relate body-mass index (BMI), systolic blood pressure (SBP), and diabetes to risk of CVD death in Cuba. Methods In a prospective cohort study, 146,665 adults were recruited from the general population in five areas of Cuba between 1996 and 2002. Participants were interviewed, measured (height, weight and blood pressure) and followed up by electronic linkage to Cuban national death registries to Jan 1 2017; 24,345 participants were resurveyed between 2006 and 2008. After excluding all with missing data or chronic disease at recruitment or, to further limit reverse causality, those who died in the first 5 years, Cox regression (adjusted for age, sex, education, smoking, alcohol and, where appropriate, BMI) was used to relate mortality rate ratios (RRs) at ages 35–79 years to BMI, SBP and diabetes. Correlations of baseline and resurvey values were used to corrected RRs for regression dilution, and thereby estimate associations with long-term average (“usual”) levels of SBP and BMI. Results After exclusions, there were 117,008 participants age 35–79 (mean age 52 [SD 12]; 55% women). At recruitment, mean SBP was 124 mm Hg (SD 15), mean BMI was 24.2 kg/m2 (SD 3.6) and 5% had diabetes; mean SBP and diabetes prevalence were both strongly related to BMI. Correlations of resurvey and baseline measurements were 0.48 for SBP and 0.60 for BMI. At ages 35–79 years, there were 3780 CVD deaths (1871 ischaemic heart disease [IHD], 766 stroke, and 1143 other). CVD mortality was positively associated with BMI (down to about 22–23 kg/m2; figure), SBP and diabetes: 10 kg/m2 higher usual BMI approximately doubled CVD mortality (RR 1.90, 95% CI 1.61–2.24), as did 20 mmHg higher usual SBP (2.03, 1.88–2.20), and a prior diagnosis of diabetes (2.18, 1.97–2.42). The associations were similar in men and women. Given these associations, about one quarter (27%) of CVD deaths in this study were attributable to these metabolic risk factors combined. Conclusion These associations differ to those reported from other parts of Latin America, and are more consistent with studies in Europe and North America, highlighting the need for many more large-scale prospective studies in low and middle income countries. This study provides direct evidence for the expected benefit on CVD mortality of addressing major metabolic risk factors in Cuba. As the levels of these metabolic risk factors are increasing in Cuba, so too is their importance as determinants of premature CVD death

Five insights from the Global Burden of Disease Study 2019

The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a rules-based synthesis of the available evidence on levels and trends in health outcomes, a diverse set of risk factors, and health system responses. GBD 2019 covered 204 countries and territories, as well as first administrative level disaggregations for 22 countries, from 1990 to 2019. Because GBD is highly standardised and comprehensive, spanning both fatal and non-fatal outcomes, and uses a mutually exclusive and collectively exhaustive list of hierarchical disease and injury causes, the study provides a powerful basis for detailed and broad insights on global health trends and emerging challenges. GBD 2019 incorporates data from 281&#x2008;586 sources and provides more than 3&#xB7;5 billion estimates of health outcome and health system measures of interest for global, national, and subnational policy dialogue. All GBD estimates are publicly available and adhere to the Guidelines on Accurate and Transparent Health Estimate Reporting. From this vast amount of information, five key insights that are important for health, social, and economic development strategies have been distilled. These insights are subject to the many limitations outlined in each of the component GBD capstone papers

Body-mass index, blood pressure and cause-specific mortality in India: Prospective study of 500 000 adults

Background The associations of cause-specific mortality with body-mass index (BMI) have been studied mainly in higher-income countries. We relate BMI and systolic blood pressure (SBP) to mortality in a South Asian population. Methods In 1998-2001, 500,810 men and women (age≥35) in Chennai city were interviewed, measured, then visited biennially from 2015, recording structured narratives of any deaths before 31.3.2015 for physician coding; in 2013-14, 10,161 participants were re-surveyed. After excluding all with missing data or chronic disease at recruitment or who died within 2 years (leaving 414,746 participants), Cox regressions (standardised for tobacco, alcohol and social factors) relate mortality rate ratios at ages 35-69 (RRs) to SBP, BMI, or BMI given usual SBP. Findings Mean SBP and BMI at recruitment were 127 mmHg (SD15) and 23 kg/m2 (SD4): correlations with re-survey measurements 14 years later were, respectively, 50% and 88%. Low BMI was strongly associated with poverty, tobacco, and alcohol. Of 29,519 deaths at ages 35-69, half were vascular (mainly cardiac). Cardiac and stroke mortality increased steeply with SBP: as in Western populations, 20 mmHg higher usual SBP approximately doubled vascular mortality, as did diabetes. But, although BMI strongly affected SBP (~1 mmHg/kg/m2) and diabetes prevalence, BMI was little related to cardiac or other vascular mortality, with only small excesses even at BMI≥30 kg/m2. After additionally allowing for the usual SBP, BMI was inversely related to cardiac and stroke mortality throughout 15-30 kg/m2; comparing under vs overweight (15-18.5 vs 25-30 kg/m2), cardiac mortality RR was 1.29 (95%CI 1.20-1.38) and stroke mortality RR was 1.47 (1.23-1.75). Interpretation In this South Asian population, BMI was little associated with vascular mortality, even though BMI increases SBP and SBP increases vascular mortality. Hence, there must be importantly adverse effects of some close correlates of below-average BMI, which could be of relevance in all populations.</p

P6258 Burden of hypertension and associated risks for cardiovascular mortality in Cuba: prospective cohort study of 150,000 men and women

Cardiovascular disease (CVD) is a leading cause of premature death in Cuba. Although raised blood pressure (BP) is an established risk factor for CVD, there is limited evidence on the prevalence and management of hypertension in Cuba

P6258 Burden of hypertension and associated risks for cardiovascular mortality in Cuba: prospective cohort study of 150,000 men and women

Cardiovascular disease (CVD) is a leading cause of premature death in Cuba. Although raised blood pressure (BP) is an established risk factor for CVD, there is limited evidence on the prevalence and management of hypertension in Cuba