Why are more women affected by arthritis than men?

Arthritis affects more women than men, period: women account for nearly 60% of suffers, with more than 26 million American women suffering from the condition. It's also the leading chronic condition among women.

It's likely that physical and hormonal differences factor into this gender discrepancy. For instance, women have less knee cartilage than men, making their knees more prone to damage and the development of arthritis. The ligaments and muscles in women's joints also are typically smaller and not as strong as they are in men, which increases the risk of injuries that can lead to osteoarthritis.

Hormones also may be involved, specifically where rheumatoid arthritis (RA) is concerned. RA is an immune condition, unlike osteoarthritis, which develops due to wear and tear on the joint. Sex hormones such as estrogen and progesterone play a critical role in the inflammatory response and in the overall regulation of the immune system. Estrogen levels have been found to be higher in arthritic cartilage than in normal cartilage, suggesting that the hormone may be significant to the development of RA in women.