Prevalence and risk factors of hip fracture in a middle-aged and older Chinese population

The prevalence of hip fracture and associated risk factors in China were evaluated in a Health and Retirement Longitudinal Study. There is an apparent geographic variation in the prevalence of hip fracture in China. Advanced age, West region, lower education, under-weight, having self-reported history of chronic lung diseases, heart diseases, stroke, and arthritis appear to be associated with risk of hip fracture. Introduction: The aim of this study is to estimate the prevalence of hip fracture and to identify its risk factors in China. Methods: Using the national survey data collected from the China Health and Retirement Longitudinal Study (CHARLS), we estimated the prevalence of hip fracture, considering the complex survey design and response rate. We applied the weighted logistic regression analysis to identify risk factors associated with hip fracture employing cross-sectional study designs. Results: Among 20,110 respondents included in the analysis, there were 431 hip fractures. The overall prevalence of hip fracture among middle-aged and older Chinese adults was 2.36%. From those aged < 50 years to 60-69 years, the prevalence of hip fracture did not increase with age, but significantly increased after the age of 70; 1.62% for those aged < 50 years and a 42% for those aged >= 70 years. East, South-Central, South-West, and North-West region had a higher prevalence of hip fracture than North and North-East region. Compared with underweight, obesity (OR 0.37 [95% CI 0.20-0.69]) was associated with a lower likelihood of hip fracture. A self-reported history of chronic lung diseases (OR 2.11 [95% CI 1.51-2.96]), heart diseases (OR 1.36 [95% CI 1.00-1.85]), stroke (OR 2.30 [95% CI 1.08-4.92]), and arthritis (OR 2.30 [95% CI 1.08-4.92]) were significantly correlated with hip fracture. Conclusions: There is an apparent geographic variation in the prevalence of hip fracture in China. Advanced age, West region, lower education, under-weight, having self-reported history of chronic lung diseases, heart diseases, stroke, and arthritis appear to be associated with risk of hip fracture. Understanding the geographic variations in hip fracture prevalence is important for allocation of healthcare resources. Knowing the reasons for hip fracture is necessary to implement a comprehensive policy for hip fracture prevention in China.