title: Physical activity as a risk factor for osteoarthritis of the knee.
abstract: A case-control study was conducted to evaluate the association between knee osteoarthritis (OA) and physical activity (PA) among a community group aged 40 years and older. Case patients (85 males, 154 females) had radiologically confirmed knee OA with grade 2+ changes, according to Kellgren and Lawrence criteria. Control subjects (85 males, 154 females) had no radiologic evidence of knee OA. A statistically significant positive association between high PA level and knee OA was observed for women, with an age-adjusted odds ratio (OR) of 1.66 and 95% confidence interval (CI) of 1.01 to 2.72. In men no association was observed (OR = 0.95; 95% CI, 0.49 to 1.83). These associations persisted when controlling simultaneously for potential confounders including age, obesity, history of knee injury, and socioeconomic status, indicating that the OA-PA association is limited to women. One possible explanation is that risk factors for knee OA are influenced by hormones.
authors.affiliation: Department of Epidemiology and Biostatistics, College of Public Health, University of South Florida, Tampa 33612-3805.
authors.forename: R L
authors.initials: RL
authors.lastname: Imeokparia
authors.forename: J P
authors.initials: JP
authors.lastname: Barrett
authors.forename: M I
authors.initials: MI
authors.lastname: Arrieta
authors.forename: P E
authors.initials: PE
authors.lastname: Leaverton
authors.forename: A A
authors.initials: AA
authors.lastname: Wilson
authors.forename: B J
authors.initials: BJ
authors.lastname: Hall
authors.forename: S M
authors.initials: SM
authors.lastname: Marlowe
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015984:Causality; D003430:Cross-Sectional Studies; D005260:Female; D005431:Florida / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007719:Knee Joint / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology / Q000209:etiology; D016273:Occupational Exposure; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000209:etiology; D005082:Physical Exertion; D011859:Radiography; D012307:Risk Factors; D016474:Weight-Bearing