Is OA linked to cancer?
In a new Swedish study by Lund University on comorbidities in osteoarthritis, researchers studied if people with osteoarthritis are at an increased risk for cancer compared to people without osteoarthritis.
The study focused on the four most common cancer types, lung, colon, breast, and prostate cancer. Researchers found no differences in the risk of being diagnosed with colon cancer if you had osteoarthritis compared to if you didn't. However, there was a 12-17% increase in the risk of being diagnosed with breast cancer for women with osteoarthritis and prostate cancer for men with osteoarthritis. Therefore, the linkage between osteoarthritis and cancer was less ambiguous than the linkage between osteoarthritis and certain other diseases.
An interesting find was that in people with knee osteoarthritis there was a 25% reduced risk of lung cancer. However, this reduced risk was not noted in patients with hip osteoarthritis. The reduced risk for people with knee OA could be due to the fact that many people with knee OA are former athletes. Smoking is the number one risk factor for lung cancer and athletes generally smoke less than people who do not play sports. Thus, the results of the study do not necessarily signalize that people with knee osteoarthritis do not get lung cancer, as data on tobacco smoking was not taken into account in the analysis.
Overall, the study suggests that there are no strong links between osteoarthritis and cancer, but that people with osteoarthritis may have other risk factors for cancer such as smoking. It may also be that cancer is detected earlier or to a greater extent in people with osteoarthritis, during a so-called "screening" or X-ray at the doctors.
There is thereby no reason for a person with osteoarthritis to worry that they are at greater risk of cancer than others. The most important thing you can do to reduce your risk of cancer is to avoid smoking and live a healthy lifestyle with a good diet and regular physical activity.