Articles
Epidemiological and demographic trends and projections in global health from 1970 to 2050: a descriptive analysis from the third Lancet Commission on Investing in Health, Global Health 2050
Angela Y Chang, Sarah Bolongaita SM, Bochen Cao, et al
Lancet 2025; 406: 940-949
https://doi.org/10.1016/S0140-6736(25)00902-X
Summary
Background
Systematic analyses of global health trends can provide an accurate narrative of progress and challenges. We analysed the impact of changing age-specific mortality (epidemiology) and age structure (demography) on crude death rates (CDRs) and causes of death with large or rising mortality to inform the third Lancet Commission on Investing in Health.
Methods
Data from the World Population Prospects 2024 and Global Health Estimates 2021 were used to assess epidemiological and demographic trends, including CDR (defined as the total number of deaths divided by the total mid-year population, reported per 1000 population), all-cause age-specific mortality rates for 1970–2050, and selected cause-specific mortality rates from 2000–19. We excluded data for 2020–23 to avoid effects of the COVID-19 pandemic. For estimating decadal changes in cause-specific mortality rates, we combined the estimates into the following age groups: 0–14, 15–49, 50–69, and 70 years and older.
Findings
Mortality rates declined substantially across age groups in most regions, with rapid improvements observed in recent decades. Between the 2000s (ie, 2000–10) and 2010s (ie, 2010–19), the mortality decline accelerated in China, central and eastern Europe, India, and Latin America and the Caribbean in ages 0–14 years and 15–49 years, but decelerated in the north Atlantic, the USA, and western Pacific and southeast Asia. For ages 50–69 years, mortality decline decelerated in all regions except sub-Saharan Africa. The USA experienced not only deceleration but increase in mortality rates in those aged 15–49 years and 50–69 years. Globally, the lowest CDR was reported in 2019. In the past, CDR has declined primarily because of decreasing age-specific mortality rates. Future trends suggest that changing population age structure will drive a large increase in CDR. Age-specific mortality rates from major diseases declined once population changes were accounted for. The exception was diabetes, with accelerating increase in age-specific death rates in all regions, with especially high rates in central and eastern Europe and India.
Table. Global decomposition of I-8 and NCDI-7 deaths into component (changes in population size, population structure, and age-specific mortality rates) contributions in 2000–10 and 2010–19
| Empty Cell | Empty Cell | Deaths, year 1* | Change in deaths | Number of deaths contributed by component (N) and share of total component effects (%) over the decade | ||
|---|---|---|---|---|---|---|
| Empty Cell | Empty Cell | Empty Cell | Empty Cell | Population size | Population structure | Age-specific mortality rates |
| I-8 deaths | ||||||
| 2000–10 | ||||||
| Childhood-cluster diseases | 1080 | −593 | +103 (13%) | −51 (6%) | −644 (81%) | |
| Diarrhoeal diseases | 2300 | −574 | +264 (21%) | +66 (5%) | −904 (73%) | |
| HIV/AIDS | 1630 | −384 | +189 (23%) | +35 (4%) | −608 (73%) | |
| Lower respiratory tract infections | 2870 | −266 | +355 (29%) | +128 (10%) | −749 (61%) | |
| Malaria | 867 | −153 | +103 (29%) | −39 (11%) | −217 (60%) | |
| Maternal conditions | 410 | −101 | +47 (24%) | 0 | −148 (76%) | |
| Neonatal conditions | 3300 | −685 | +384 (26%) | −175 (12%) | −894 (62%) | |
| Tuberculosis | 2520 | −586 | +293 (19%) | +185 (12%) | −1060 (69%) | |
| I-8 | 15 000 | −3340 | +1740 (24%) | +148 (2%) | −5230 (74%) | |
| 2010–19 | ||||||
| Childhood-cluster diseases | 485 | −193 | +42 (15%) | −26 (9%) | −209 (76%) | |
| Diarrhoeal diseases | 1730 | −406 | +165 (19%) | +58 (7%) | −628 (74%) | |
| HIV/AIDS | 1250 | −534 | +107 (14%) | +5 (1%) | −646 (85%) | |
| Lower respiratory tract infections | 2600 | +29 | +279 (33%) | +158 (19%) | −408 (48%) | |
| Malaria | 713 | −135 | +69 (25%) | −44 (16%) | −160 (58%) | |
| Maternal conditions | 310 | −70 | +30 (23%) | −10 (8%) | −89 (69%) | |
| Neonatal conditions | 2610 | −553 | +250 (24%) | −291 (28%) | −512 (49%) | |
| Tuberculosis | 1930 | −606 | +177 (15%) | +125 (10%) | −909 (75%) | |
| I-8 | 11 600 | −2470 | +1120 (24%) | −25 (1%) | −3560 (76%) | |
| NCDI-7 deaths | ||||||
| 2000–10 | ||||||
| Atherosclerotic CVD | 8990 | +1600 | +1270 (30%) | +1660 (39%) | −1330 (31%) | |
| Diabetes | 1080 | +392 | +164 (42%) | +180 (46%) | +48 (12%) | |
| Haemorrhagic stroke | 3060 | +261 | +414 (28%) | +457 (31%) | −611 (41%) | |
| Infection-associated NCDs | 2310 | +146 | +309 (29%) | +296 (28%) | −460 (43%) | |
| Road injury | 1180 | +67 | +157 (47%) | +45 (13%) | −136 (40%) | |
| Strongly tobacco-associated NCDs | 4530 | +526 | +621 (28%) | +757 (34%) | −851 (38%) | |
| Suicide | 771 | −22 | +99 (31%) | +48 (15%) | −168 (53%) | |
| NCDI-7 | 21 900 | +2970 | +3030 (30%) | +3440 (34%) | −3510 (35%) | |
| 2010–19 | ||||||
| Atherosclerotic CVD | 10 600 | +1470 | +1210 (26%) | +1870 (40%) | −1610 (34%) | |
| Diabetes | 1470 | +533 | +184 (35%) | +258 (48%) | +91 (17%) | |
| Haemorrhagic stroke | 3330 | +161 | +365 (23%) | +503 (32%) | −708 (45%) | |
| Infection-associated NCDs | 2460 | +119 | +270 (26%) | +311 (30%) | −462 (44%) | |
| Road injury | 1250 | −54 | +131 (34%) | +32 (8%) | −217 (57%) | |
| Strongly tobacco-associated NCDs | 5050 | +758 | +580 (27%) | +874 (41%) | −696 (32%) | |
| Suicide | 749 | −14 | +80 (34%) | +30 (13%) | −123 (53%) | |
| NCDI-7 | 24 900 | +2970 | +2820 (27%) | +3880 (37%) | −3720 (36%) | |
CVD=cardiovascular disease. I-8=eight infections and neonatal and maternal health conditions. NCDs=non-communicable diseases. NCDI-7=seven NCDs and injuries.*
The first year of the decadal period (2000 for 2000s, 2010 for 2010s). Deaths in thousands.
Interpretation
There is reason for optimism regarding global health progress, but disparities and emerging challenges persist. Falling age-specific mortality rates show progress; however, rapid ageing brings new challenges. Slowing mortality declines in some regions require enhanced efforts. Rising mortality among middle-aged Americans emphasises that continuous improvements require concerted efforts. Key recommendations include prioritising interventions to address specific health challenges and adapting health-care systems to demographic transitions.
Funding
The Norwegian Agency for Development Cooperation and the Bill & Melinda Gates Foundation.
