Why Is Osteoarthritis in Women More Common Than in Men?

Osteoarthritis (OA) is a leading cause of disability in the United States, and individuals with the disease experience a great amount of pain and loss of function. Interestingly, studies show that rates of Osteoarthritis in women are higher than in men. Overall, of the 27 million people diagnosed with OA in the US, roughly 60 percent of those suffering from the disease are women.

Some Interesting Facts:

• OA tends to be more prevalent in men prior to the age of 55, the number of women with the condition exceeds that of men for individuals older than 55.
• The joints themselves affected by OA also seem to vary by sex. While men are more likely to have arthritis of the hip, women are generally at greater risk for experiencing the disease in the knee or hand.

A number of reasons have been proposed for why this is, and it appears as if biology is a leading factor.

Because a woman’s body is built in a manner suited for childbearing, her lower body tendons are usually more elastic than a man’s. Due to this increased elasticity, the joints are able to move more and are therefore slightly less stable, making them more prone to injury and osteoarthritis in women. A woman’s hips are also wider than their knees, often causing knee joints to be misaligned. This alignment leads to higher rate of injury, especially in women who are physically active. For example, studies have shown that female soccer players have experienced three to four times the number of knee injuries than male soccer players.

An increased risk of injury is directly correlated to an increased risk of osteoarthritis later on in life.

It has also been shown that OA is genetic, meaning that it often runs in particular families. More specifically, there seems to be a female genetic link for the disease that is passed on through generations of women, especially in OA of hands and knees. Chances are, if a woman’s mother has OA, she is likely to develop OA in the same joint around the same age that her mother developed the disease.

Furthermore, researchers believe that female hormones, particularly estrogen, effect joint cartilage by protecting it from inflammation. This is important because inflammation is one of the leading causes of OA. Because women’s estrogen levels drop significantly following menopause, they often lose this protection, which places them at a higher risk of developing OA.

In addition, it is well understood that obesity plays a significant role in OA because it places additional stress on the joint. For every additional pound of gained weight, three pounds of pressure load are placed on the knees. Because statistics have shown that more women are more likely to be obese than men, this again puts women at greater risk of OA.