How lifestyle factors influence the development and progression of OA
The worldwide obesity epidemic in older adults is fueling an increase in many chronic diseases, including osteoarthritis (OA). The OARSI recommendations for the management of hip and knee osteoarthritis recognize lifestyle factors, including weight loss and physical activity, as primary non-pharmacologic therapies. Obesity has long been a recognized risk factor for the development of knee OA and influences disease progression. Physical activity is a more recent addition to non-pharmaceutical interventions. Recent randomized clinical trials provide insight into the synergy between weight loss and physical activity in knee OA. Exercise alone and weight loss alone were each effective to improve function; however weight loss plus exercise had the greatest benefit. Current evidence supports physical activity interventions which increase moderate intensity activity. However, many adults are not candidates to engage in moderate intensity activities due to health limitations. What strategies are available to these adults? Recent work demonstrated sedentary behavior is a significant risk factor for functional loss in adults including adults with knee OA. Taken as a whole, lifestyle interventions provide important strategies to prevent knee OA and its consequences. For overweight adults with knee OA, weight loss plus engaging in physical activity of moderate intensity can improve function and reduce disability. Reducing time spent in sedentary behavior such as sitting may be beneficial for adults with mobility limiting chronic conditions. Effective nonpharmacologic strategies for adults with OA will control weight, promote physical activity, and reduce sedentary activities such as sitting.