Epidemiological studies of OA in the general population have shown that old age, female gender, being overweight or obese, knee injury, repetitive use of joints, black race, muscle weakness, and genetics play a role in OA development (Clin. Geriatr. Med. 2010;26:355-69).
Meanwhile, no medications have proven effective in preventing OA, and research on cartilage repair is still developing.
Black race was also shown to be associated with higher incidence rate of OA, compared with white race and those in the "others" category.
A few studies, including several by Dr. Nelson’s group, have shown that blacks are more likely to have severe knee and hip OA. "This study confirms our findings," she said.
The authors cited several limitations, including potential for coding errors, potential for information bias due to misclassification of the outcome of interest, lack of incidence rates for specific sites, and definitions used for incident cases of OA (physician-diagnosed vs. patient self-report, radiographic criteria or combination of both.)
Despite its limitations, some experts believe that the study’s findings support those of previous reports on OA.
Dr. Thomas M. Link, professor of radiology and clinical director of musculoskeletal and quantitative imaging research at the University of California, San Francisco, said, "The key message is that prevention is more important than anything else."
Several programs such as RunSafe Healthy Runners Clinic at the University of California, San Francisco, try to reduce the odds of injury by making slight modifications in how the athletes run, and their work has proven effective, said Dr. Link.
"I think what we found in the study is consistent with what we expected. The next question is why that is, and what are the modifiable risk factors," said Dr. Cameron.
The authors reported no conflicts of interest.