Abstract P311: Lifestyle Factors Substantially Contributed to Urban-Rural Disparity in All-Cause Mortality Among Chinese Adults 65 or Older

Background: Studies on whether lifestyle factors could explain urban-rural differences in mortality risks among Chinese adults 65 years or older are limited. We aim to assess whether and to what extent individual-level lifestyle factors contribute to urban-rural disparity in mortality among older Chinese adults. Methods: Our study included a total of 37,083 adults 65 years or older residents (8,522 city, 8,022 urban and 20,539 rural) from seven waves of the Chinese Longitudinal Healthy Longevity Survey (1998-2014), with follow-up to the latest wave (2018). Five lifestyle factors were examined: smoking, drinking, physical activity, diet and leisure activities. All-cause mortality was ascertained through death registry and information from next of kin. We conducted multivariable Cox proportional hazard models to examine mortality risks and used two measures to estimate the contributions to urban-rural mortality disparity from lifestyle factors, PERM (percentage excess risk mediated) calculated by the change of hazard ratio of the different models divided by the hazard ratio of the adjusted demographics model and AUC (area under the receiver-operating curve). Results: During a median follow-up of 3.24 years, 23,576 death cases were recorded. Report crude differences (death rates by the 3 groups city, town, rural) before adjusting for any vars. After adjusting for demographics, the hazards for town and rural residents were 8.8% and 17.2% higher than city residents, respectively (Table 1, Model 1). Adjustment for leisure activities made the largest difference in explaining the urban-rural disparities (Model 6). Adjustment for all five lifestyle factors explained 36.6% of city-town and 26.1% of city-rural differences (Model 7). AUCs for all models were > 0.7. Conclusion: Lifestyle factors, especially leisure activities, physical activities and diet, contributed substantially to the urban-rural disparity in all-cause mortality of adults aged 65 years or older in China.