[A cohort study on the influence of the chronic diseases on falls among middle-aged and older Chinese]

Objective: To analyze the influence of chronic diseases on falls among middle-aged and older Chinese. Methods: Baseline data of 13 670 middle-aged and older adults recruited from China Health and Retirement Longitudinal Study (CHARLS) in 2011 were used and followed up to 2018, among those were 7 443 (54.45%) middle-aged people aged 45-59 and 6 227 (45.55%) older adults aged 60 and above. The Cox proportional hazards model was used to analyze the effects of different types, the number of chronic diseases and the interaction between chronic illness and other factors on the fall risk of middle-aged and older people. Results: After adjusting for confounding factors, respiratory diseases increased the risk of falls by 21% (HR=1.21, 95%CI:1.02-1.45), and arthritis increased the risk of falls by 27% (HR=1.27,95%CI: 1.12-1.43) in the group aged 45-59, kidney disease increased the risk of falls by 26% (HR=1.26, 95%CI: 1.03-1.53) in the group aged 60 and above. A linear dose-response relationship between the number of chronic diseases and fall risk (χ2=133.61, P<0.001) was found in all the age groups. The interaction between having chronic diseases and the factors of females (HR=1.64, 95%CI: 1.43-1.89), impaired activities of daily living (ADL) (HR=1.66, 95%CI: 1.39-1.99), and having a fall history (HR=2.58, 95%CI: 2.24-2.97) increased the risk of falls. Conclusions: There is a positive linear relationship between the number of chronic diseases and the fall risk among Chinese aged 45 and above. The female middle-aged and elderly patients with chronic diseases and the middle-aged and elderly patients with impaired ADL or a history of falls are the high-risk groups for falls that need to be focused on intervention. The window of fall injury prevention should be moved forward to the middle-aged stage in time.