However, Dr. Callahan urges rheumatologists to encourage physical activity for their patients.
The ACR published recommendations in 2012 for healthcare providers on counseling patients with arthritis on physical activity.5 Strong recommendations for patients with knee OA included:
- Participation in cardiovascular (aerobic) and/or resistance land-based exercise;
- Participation in aquatic exercise; and
- Weight loss (for overweight patients).
“Although the evidence supporting the use of physical activity for primary prevention of OA is not established, the evidence is solid that once someone has OA, physical activity has positive benefits,” Dr. Callahan says. “There is also overwhelming evidence that physical activity is good for overall health, and the evidence to date appears to indicate it does not cause OA, so appropriate activity should be recommended.”
Is Knee OA Preventable?
According to Dr. Wallace, thinking about physical activity as a potential risk factor suggests knee OA may be preventable. “From a clinical perspective, the real message is that the disease does seem to be more preventable than clinicians commonly acknowledge,” he says. “To develop robust preventative strategies, however, we have to start exploring different candidates for what the causes are for this disease.”
Dr. Felson agrees. “I’d say weight is part of the picture, and physical activity is part of the picture, and probably other factors that we have not well identified are part of the picture, too.” He thinks diet is one of those factors.
We need a better understanding of all the risk factors that may make knee OA a preventable disease. Looking back to earlier times to track disease prevalence is one way in which the risk factors may emerge, drawing from a better understanding of the conditions from which humans evolve and adapt to their changing environments.
Mary Beth Nierengarten is a freelance medical journalist based in Minneapolis.
References
- Murray CJ, Vos T, Lozano R, et al. Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990–2010: A systematic analysis for the Global Burden of Disease Study 2010. Lancet. 2012 Dec 15;380(9859):2197–2223.
- Deshpande BR, Katz JN, Solomon DH, et al. The number of persons with symptomatic knee osteoarthritis in the United States: Impact of race/ethnicity, age, sex, and obesity. Arthritis Care Res (Hoboken). 2016 Dec;68(12):1743–1750.
- Wallace IJ, Worthington S, Felson DT, et al. Knee osteoarthritis has doubled in prevalence since the mid-20th century. Proc Natl Acad Sci USA. 2017 Aug 29;114(35):9332–9336.
- Callahan LF, Ambrose KR. Physical activity and osteoarthritis – considerations at the population and clinical level. Osteoarthritis Cartilage. 2015 Jan;23(1):31–33.
- Hochberg MC, Altman RD, April KT, et al. American College of Rheumatology 2012 recommendations for the use of nonpharmacologic and pharmacologic therapies in osteoarthritis of the hand, hip, and knee. Arthritis Care Res (Hoboken). 2012;64(4):465–474.
