March 30, 2010 -- Women have a lower risk of developing gout than men, even when they have the same blood levels of the chemical that causes the painful, inflammatory arthritis, new research shows.
Gout has traditionally been thought of as a disease of older men, but older women get it, too. A recent national health survey found that about 4% of women in their 60s and 6% of those in their 80s had gout.
In one of the first large studies to examine gout by gender, researchers found that in women, just as in men, older age, obesity, high blood pressure, alcohol use, and use of diuretics are all risk factors for gout.
Gout occurs when elevated blood levels of uric acid form crystals in the joints and surrounding tissue, leading to excruciatingly painful inflammation and swelling.
The big toe, knee, and ankle joints are the most common sites for gout, and attacks frequently start during the night. The painful swelling typically goes away in a few days, but more than half of people who have one attack will have others.
In an effort to better understand the impact of gender on gout, researchers from Boston University School of Medicine examined data on 2,476 female and 1,951 male participants in the ongoing Framingham Heart Study, which has followed residents of Framingham, Mass., since the late 1940s.
Over an average of three decades of follow-up, 304 cases of gout were reported, with one-third of those cases occurring in women.
For both sexes, gout incidence rose with increasing uric acid levels. But the association was stronger for men than for women.
Women with serum uric acid levels over 5 milligrams/deciliter had a significantly lower risk of developing gout than men with identical uric acid levels.
Other gender differences identified by the researcher include:
A higher proportion of women than men had high blood pressure and were being treated with diuretics. This finding suggests these two risk factors may be more important for women than men, the researchers say.
Drinking 7 or more ounces of spirits a week -- roughly five drinks -- doubled the gout risk in men and tripled it in women. Heavy beer drinking was associated with a doubling of risk among men and a sevenfold increase in risk among women.