RA Is on the Rise in Women
Researchers from the Mayo Clinic reported in 2008 that while RA appears to have been on the decline from 1955 and 1994 in the U.S., that no longer appears to be the case for women. The study found that from 1995 to 2005 the number of women who got RA increased by nearly 50% over the number that got it in the previous decade. RA rates among men remained stable.
Studies Show RA To Be More Severe in Women
In a large study released in 2009, researchers found that women with RA reported more symptoms — and more severe symptoms — even when they appeared to have the same level of the disease as men. Women also did not respond as well to the same treatment — both in terms of what their doctors could measure, like swollen joints, and in terms of how they described their symptoms.
Why the difference? Researchers aren’t sure. One theory is that women may have a more severe form of RA. Another is that that muscle mass may be a factor — men tend to have more muscle mass than women. Some scientists speculate that the medicines used to treat RA may affect women and men differently.
The Role of Hormones in RA
It’s likely that hormones play a large role in the differences in RA between men and women. Women often develop the disease at times when their sex hormones are changing, such as after pregnancy or around menopause. Rheumatoid arthritis also tends to go into remission during pregnancy and often flares again after delivery.
Breastfeeding lowers the risk of rheumatoid arthritis in women. A 2004 study showed that women who breastfed for two years or more cut their risk of rheumatoid arthritis in half.