Associations of occupational tasks with knee and hip osteoarthritis: the Johnston County Osteoarthritis Project.

OBJECTIVE: This cross-sectional study examined associations of occupational tasks with radiographic and symptomatic osteoarthritis (OA) in a community-based sample.
METHODS: Participants from the Johnston County Osteoarthritis Project (n = 2729) self-reported the frequency of performing 10 specific occupational tasks at the longest job ever held (never/seldom/sometimes vs often/always) and lifetime exposure to jobs that required spending > 50% of their time doing 5 specific tasks or lifting 22, 44, or 110 pounds 10 times weekly. Multivariable logistic regression models examined associations of each occupational task separately with radiographic and symptomatic knee and hip OA, controlling for age, race, gender, body mass index, prior knee or hip injury, and smoking.
RESULTS: Radiographic hip and knee OA were not significantly associated with any occupational tasks, but several occupational tasks were associated with increased odds of both symptomatic knee and hip OA: lifting > 10 pounds, crawling, and doing heavy work while standing (OR 1.4-2.1). More occupational walking and standing and less sitting were also associated with symptomatic knee OA, and more bending/twisting/reaching was associated with symptomatic hip OA. Exposure to a greater number of physically demanding occupational tasks at the longest job was associated with greater odds of both symptomatic knee and hip OA.
CONCLUSION: Our results confirm an association of physically demanding occupational tasks with both symptomatic knee and hip OA, including several specific activities that increased the odds of OA in both joint groups. These tasks represent possibilities for identifying and targeting at-risk individuals with preventive interventions.