Overweight men at risk of osteoarthritis of both hip and knee

People who are overweight are known to be more likely to get osteoarthritis of the knee, but this is the first study to show that being overweight is a risk factor for hip osteoarthritis in men but not women.

Researchers compared the body mass indexes of 1,473 Icelandic people who had undergone hip or knee replacement with those of 1,103 people who had not had joint replacement surgery. All were born between 1910 and 1939.

They found women who were overweight (BMI>25) were no more likely to have had a hip replacement than women of normal weight, but men were. Men who were obese (BMI>30) were 70 per cent more likely to have had hip replacement surgery.

People of both sexes who were overweight were much more likely to have had knee replacement surgery and the more overweight they were the more likely it was. Men who were obese were five times more likely to have had a replacement knee and women four times more likely.

The authors say: “The study supports a positive association between high BMI and total knee replacement in both sexes, but for total hip replacement the association with BMI seems to be weaker, and possibly negligible for women.”

Source: British Medical Journal