The Modified Healthy Ageing Index Is Associated with Mortality and Disability: The Rugao Longevity and Ageing Study

Introduction: The Healthy Ageing Index (HAI) has been shown not only to have wider applicability and predictive ability but also to adequately predict mortality in Western populations. There is still a lack of studies validating the applicability of the HAI in China. Objective: To evaluate the applicability of the HAI and validate whether the HAI is suitable for monitoring ageing in the elderly population in China. Methods: Data were obtained from the Rugao Longevity and Ageing Study. The modified HAI was constructed based on systolic blood pressure, chronic pulmonary diseases, cognitive function, fasting glucose, and kidney function. It was calculated in 1719 individuals aged 70-84 years at baseline. The adverse outcomes were mortality and disability. Demographic, physiologic, and clinical data were collected. Cox proportional hazards and logistic regression models were used to analyze the relationship between the modified HAI and adverse outcomes. Results: A total of 1,719 older adults were analyzed in our study. A total of 793 (46.13%) males were recruited. The mean age was 75.69 +/- 3.93 years. At the 5-year follow-up, there were 266 deaths and 275 individuals with disabilities. In the multivariable models, the modified HAI was associated with mortality (hazard ratio = 1.11, 95% confidence interval [CI]: 1.03-1.20) and disability (odds ratio = 1.11, 95% CI: 1.05-1.18). In the sensitivity analyses, similar associations remained after imputing missing data using multiple imputation and excluding participants with major cardiovascular disease at baseline. Conclusion: The modified HAI was a robust and independent predictor of adverse outcomes. It is a valid and feasible tool for monitoring ageing in older adults.