Mortality risk, life expectancy loss, and economic burden attributable to modifiable risk factors: Evidence from a large prospective cohort study in China

Despite the health impacts of socioeconomic status, physical inactivity, and air pollution being well-documented, fewer studies have quantified their combined effects on mortality, life expectancy, and economic burden. This prospective cohort study used data from the China Health and Retirement Longitudinal Study (CHARLS, 2011 - 2020). Cox proportional hazards regression estimated HRs and population attributable fractions (PAF) for eight modifiable risk factors. Flexible Cox models assessed life expectancy changes using a risk score. Economic burden was estimated using the Value of a Statistical Life (VSL). This study included 19,846 participants aged 45 and older from 28 provinces. The Combined PAF of mortality due to the eight modifiable risk factors was 71.64%, with major contributions by low socioeconomic status (37.01%), low physical activity (27.64%), and high PM 2.5 exposure (13.87%). Life expectancy losses were 4.48 years for current smokers and 3.19 years for current drinkers; former smokers and drinkers lost 4.49 and 4.64 years, respectively. Each one-point increase in the risk score was associated with an average loss of approximately 2 years in life expectancy at age 45. Participants with a score of zero were expected to live 18.37 years longer than those scoring nine. The average economic loss attributable to these risk factors was 1,833.95 million US dollars per 100,000 population. Subgroup analyses revealed greater impacts in rural and northern regions. Modifiable risk factors contribute substantially to mortality, reduced life expectancy, and economic losses among middle-aged and older adults, highlighting the need for targeted public health strategies. • We assess mortality, life expectancy loss, and economic burden from modifiable risk factors in China. • The combined impact of multiple modifiable risk factors was evaluated, rather than individual exposures alone. • Rural and Northern regions exhibited greater health and economic burdens. • Targeted public health strategies are urgently needed to reduce preventable deaths and support healthy aging.