Prevalence and risk factors of knee osteoarthritis in Huang-Pu District, Shanghai, China.
OBJECTIVE
A community-based survey on the prevalence of knee osteoarthritis (OA) and associated factors was carried out in Shanghai, People's Republic of China.


METHODS
Of 2,305 registered residents >or=40 years of age, 2,093 were examined by interview and questionnaire. One hundred ninety knee pain-positive and 510 knee pain-negative subjects received radiography.


RESULTS
Radiographic knee OA (RKOA) was found in 72.1% (137/190) of symptomatic and 41.6% (212/510) of asymptomatic subjects (SKOA and AsKOA, respectively). The estimated prevalences of symptomatic and asymptomatic knee OA in the community were 7.2% and 37.4%, respectively. Women had higher SKOA prevalence than men (9.8% vs 3.7%, P<0.01). Compared with Caucasians, the urban Shanghai population had a higher prevalence of tibiofemoral joint OA.


CONCLUSIONS
There was a higher proportion of SKOA than AsKOA (72.1% vs 41.6%), and SKOA was significantly more associated with disability (81.0% vs 26.9%, P<0.01). The prevalence of SKOA increased with age, from 1.3% in the 40-49-year-old age group to 13.2% in the 70+ group. Age, body mass index, and female gender were associated risk factors for knee OA.
Du
Hui
H
Department of Rheumatology and Clinical Immunology, Ren Ji Hospital, No. 2 Medical University, Shanghai, China 200001.
Chen
Shun-Le
SL
Bao
Chun-De
CD
Wang
Xiao-Dong
XD
Lu
Yu
Y
Gu
Yue-Ying
YY
Xu
Jian-Rong
JR
Chai
Wei-Min
WM
Chen
Jie
J
Nakamura
Hiroshi
H
Nishioka
Kusuki
K
D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors