ABSTRACT
BACKGROUND: Investigation on epidemiologic features of knee osteoarthritis in many areas of China has been much reported. However, multicenter studies with large samples have been rarely reported. The published papers cannot give a good description about the epidemiologic features of knee osteoarthritis. OBJECTIVE: To evaluate the epidemiologic features of knee osteoarthritis in the patients aged over 40 years in China. METHODS: Meta-analysis was used to evaluate the data extracted from papers published 2001-2016 on the epidemiology of knee osteoarthritis in the middle-aged and elderly in China. The prevalence rate of knee osteoarthritis in the patients over 40 years of age was summarized, with every 10 years as group, and then analyzed on Stata 12.0 software. RESULTS AND CONCLUSION: Twenty-six articles were included, involving 42 199 people aged more than 40 years old. The total prevalence rate of knee osteoarthritis at the age above 40 years old in China was 17.0% (95% CI:16.7%-17.4%),the prevalence rate was 12.3% in male and 22.2% in female(P<0.05).Noticeably,the prevalence rate increased with age.The total prevalence rate in northern China was 16.1%(95% CI:15.6%-16.6%),12.2% in male and 21.4% in female;the total prevalence in southern China was 18.0%(95%CI:17.5%-18.5%), 12.3% in male and 23.1% in female. There was no significant difference in the prevalence rate between northern and southern China(P>0.05).The total prevalence rate in rural China was 23.6%(95%CI:16.7%-30.4%),with 15.4% in male and 28.1% in female;and the total prevalence in urban China was 20.0%(95% CI:16.2%-23.9%),with 13.7% in male and 24.3% in female. There was no significant difference in the prevalence rate between rural and urban China (P > 0.05). These results suggest that knee osteoarthritis in China is a common disease, characterized by increased prevalence with age, relatively significant difference between male and female, but no difference between northern and southern China as well as between rural and urban China. It is of great significance to timely propagate and perform interventional strategies for prevention and treatment of knee osteoarthritis in China.