Measurement and projection of the burden of disease attributable to population aging in 188 countries, 1990-2050: A population-based study

Quantitative attribution of the burden of disease due to population aging is an important part of setting meaningful global health priorities. This study comprehensively examines the burden of disease attributable to population aging in 188 countries from 1990 to 2019, incorporates a comprehensive range of diseases, and projects the burden of disease due to population aging till 2050.We extracted data from 1990 to 2019 for 188 countries from the Global Burden of Disease Study 2019. We decomposed the change in disease burden into the contribution of the age structure of the population, population size, and age-specific disability-adjusted life years (DALYs) rates due to all other reasons. We used the Bayesian age-period-cohort model to evaluate the effects of age on temporal trends, and then to predict the possible disease burden in 2050.At the global level, the change in total DALYs associated with age structure, population size, and all other reasons is 27.4%, 16.8%, and 89.4% (absolute level of DALYs attributable to age structure: -15.20 million, 9.32 million, and -49.58 million) of the absolute level of DALYs gap between 2019 and 1990. The absolute level of DALYs changes attributable to age structure for communicable, maternal, neonatal, and nutritional diseases were negative in all income groups from 1990 to 2019. For non-communicable diseases, the contribution was positive except in the low-income group. For injuries, the contribution was positive in lower-middle-income groups and low-income groups. By 2050, DALY rates decreased in all income groups, if compared to 2019. However, a total of 132 countries may see a gradual increase of all-cause DALYs attributable to population aging.The direction and intensity of the effects of population aging on the burden of disease vary by region and disease, with huge implications for global health in the future.