Prevalence and risk factors of arthritis in a middle-aged and older Chinese population: The China health and retirement longitudinal study

Objectives. The aims of this study were to estimate the prevalence of arthritis and to identify risk factors of arthritis in a middle-aged and older Chinese adult population. Methods. The China Health and Retirement Longitudinal Study (CHARLS) national survey data were used to estimate overall arthritis prevalence and prevalence by age and gender groups taking into account the complex survey design and response rate. The PROC SURVEYLOGISTIC procedure (SAS 9.3; SAS Institute, Cary, NC, USA) was applied to identify factors associated with arthritis using the CHARLS national survey data. Significant factors were further evaluated in the longitudinal CHARLS pilot study. Results. The overall prevalence of arthritis among middle-aged and older Chinese adults was 31.4% (95% CI 30.3, 32.4). Prevalence increased with age. Females had a higher prevalence of arthritis than males in each age group. In the cross-sectional analysis, age, gender, education, BMI, sleep duration, vigorous physical activity and self-reported doctor-diagnosed chronic lung disease, hypertension, chronic liver disease, cardiovascular disease, stroke, chronic kidney disease and chronic digestive disease were associated with arthritis. Age, gender, vigorous physical activity and cardiovascular disease were confirmed to be risk factors of arthritis in the longitudinal analysis. Participants with cardiovascular disease were 1.67 times (95% CI 1.02, 2.74) more likely to have self-reported arthritis in a 4-year period of follow-up in the CHARLS pilot study. Conclusion. Middle-aged and older Chinese adults had a high prevalence of arthritis. Cardiovascular disease is a novel risk factor for arthritis in this population.