Quantifying the loss of healthy life expectancy due to population ageing: health benefit estimation from a global perspective.

STUDY OBJECTIVE

Investing in health to improve healthy life expectancy (HLE) is fundamental to create a demographic dividend. However, how dramatic population ageing affects HLE remains unknown. This study aims to quantify and project the major diseases and injuries attributed to changes in population size and age structure that contributed to substantial losses in HLE.

METHODS

Using data from 188 countries in the Global Burden of Disease Study 2021 and World Population Prospects 2024, we assessed the correlation between HLE and total dependency ratios. Furthermore, we decomposed the mortality and disability burden attributable to changes in population size as well as age structure for 22 disease and injury categories and then quantified the loss of HLE due to the attributable burden. Additionally, we projected the loss of HLE due to priority diseases in 2030, while considering the impact of population ageing.

RESULTS

From 2010 to 2019, globally, the mortality and disability burden attributable to age structure caused 0.40 years and 0.71 years of HLE loss, while for population size, these two estimates were 1.18 years and 1.00 years. By 2030, the mortality and disability burden attributable to age structure may lead to 0.76 years and 0.89 years of HLE loss, while for population size, these two predictions will be 1.21 years and 1.17 years.

DISCUSSION

Population size growth is a consistent and crucial contributor to HLE losses. Reaping the second demographic dividend requires eliminating the double burden of premature death caused by infectious and chronic diseases, whereas gaining the sustainable third demographic dividend requires investments in healthy and successful ageing.