Urban health advantage or urban health penalty? Urban-rural disparities in age trajectories of physiological health among Chinese middle-aged and older women and men.

During the past decades, China has experienced rapid urbanization and aging. This study investigated sex-stratified urban-rural disparities in age trajectories of physiological health in China. We obtained data from 21686 individuals aged 45 years or above from 2011 baseline survey of the China Health and Retirement Longitudinal Study (CHARLS) and the 2015 follow-up. It examined 11 biomarkers of physiological health classified into four summary indices: cardiovascular index, metabolic index, inflammation index, and allostatic load. This study found that the "urban health penalty" approach dominates the "urban health advantage" approach in middle and early old age, but the dominance of the "urban health penalty" approach is offset or even reversed by the "urban health advantage" approach in older age.