Weight Loss and Exercise for Communities With Arthritis in North Carolina

Obesity is a modifiable risk factor for knee osteoarthritis (OA), and weight loss is an effective non-pharmacologic treatment to reduce pain. Recently, the investigators determined that under ideal, highly controlled circumstances, a diet-induced weight loss of 10% combined with exercise was significantly better at reducing pain than either intervention alone. Compared to the investigators previous longterm weight loss and exercise trials of knee OA, the diet-induced weight loss and exercise group was twice as effective at relieving pain. Whether the investigators results can be generalized to less rigorously monitored patient cohorts is unknown. Thus the challenge the investigators now face is to provide the practical means to implement this proven treatment in the community setting. This study aims to develop and demonstrate the effectiveness of a systematic, practical, cost-effective diet-induced weight loss and exercise intervention in both urban and rural communities that can reduce pain and improve other clinical outcomes in knee OA patients. This pragmatic community-based trial will determine if the investigators previous findings translate to real-world settings and will address common concerns about barriers to effectiveness/ implementation.

Participants will be 820 ambulatory, community-dwelling, overweight and obese men and women who meet the American College of Rheumatology clinical criteria for knee OA. The primary aim is to determine whether a pragmatic, community-based 18-month diet-induced weight loss and exercise intervention implemented in three North Carolina counties with diverse residential (from urban to rural) and socioeconomic composition significantly decreases knee pain in overweight and obese adults with knee OA relative to an attention control group. Secondary aims will determine whether this intervention improves self-reported function, health-related quality of life, and mobility. The investigators will also establish the cost-effectiveness of this pragmatic, community-based, multimodal diet-induced weight-loss and exercise program by conducting cost-effectiveness and budgetary impact analyses using data from the current trial in a validated computer-simulated model of knee OA.

Many physicians who treat people with knee OA have no practical means to implement weight loss and exercise treatments. This study is significant in that it will test the effectiveness of a long-awaited and much needed community-based program that will serve as a blueprint for clinicians and public health officials in both urban and rural communities to implement a weight loss and exercise program designed to reduce knee pain and improve other clinical outcomes in overweight and obese people with knee OA that can be sustained long-term and at a reasonable cost.

Inclusion criteria

• age ≥ 50
• Knee Pain plus American College of Rheumatology (ACR) Criteria for Knee Osteoarthritis
• BMI = 27 ≥ kg/m2

Exclusion criteria

• Significant co-morbid disease that would threaten safety or impair ability to participate in interventions or testing (Blindness; Type 1 diabetes; Severe coronary artery disease)
• Not sufficiently overweight or obese, BMI < 27 kg/m2
• Not having knee pain
• Inability to finish 18-month study or unlikely to be compliant (Planning to leave area > 2 month during the next 18 months; Unwilling to change eating or physical activity habits; Unwilling to discontinue pain medication use for 3 days prior to testing visit)
• Age, age < 50
• Other conditions that may prohibit the effective delivery of the intervention (Unable to provide own transportation to exercise center; Unable to read or write)