BOSTON, July 28 (UPI) -- The prevalence of gout has increased in the past 20 years, and it now affects 8.3 million Americans, or 4 percent of the population, researchers say.
The study, published in the journal Arthritis & Rheumatism, says the greater frequency of obesity and hypertension in the past 20 years may be associated with the increase in gout.
Senior investigator Dr. Hyon Choi of Boston University School of Medicine says gout, an inflammatory arthritis triggered by crystallization of uric acid within the joints, causes severe pain and swelling.
Medical evidence suggests gout is strongly associated with metabolic syndrome -- a group of health conditions characterized by central obesity, insulin resistance, high-blood pressure and blood lipid issues -- and may lead to heart attack, diabetes and premature death, Choir says.
The researchers compared data from the latest U.S. National Health and Nutrition Examination Survey in 2007 and 2008, with those from previous surveys in 1988 to 1994.
Researchers defined hyperuricemia -- a level of uric acid in the blood that is abnormally high -- as serum urate level greater than 7.0 milligrams per liter in men and 5.7 mg/dL in women.
The study finds increased hyperuricemia, also rose, affecting 43.3 million, or 21 percent of U.S. adults.
