Body mass index, obesity, and prevalent gout in the United States in 1988-1994 and 2007-2010

Objective To determine the association and prevalence of gout among overweight, obese, and morbidly obese segments of the US population. Methods Among participants (age =20 years) of the National Health and Nutrition Examination Surveys in 19881994 and 20072010, gout status was ascertained by self-report of a physician diagnosis. Body mass index (BMI) was examined in categories of <18.5 kg/m2, 18.524.9 kg/m2, 2529.9 kg/m2, 3034.9 kg/m2, and =35 kg/m2 and as a continuous variable. The cross-sectional association of BMI category with gout status was adjusted for demographic and obesity-related medical disorders. Results In the US, the crude prevalence of gout was 12% among participants with a normal BMI (18.524.9 kg/m2), 3% among overweight participants, 45% with class I obesity, and 57% with class II or class III obesity. The adjusted prevalence ratio comparing the highest to a normal BMI category was 2.46 (95% confidence interval [95% CI] 1.444.21) in 19881994 and 2.21 (95% CI 1.503.26) in 20072010. Notably, there was a progressively greater prevalence ratio of gout associated with successively higher categories of BMI. In both survey periods, for an average American adult standing 1.76 meters (5 feet 9 inches), a 1-unit higher BMI, corresponding to 3.1 kg (similar to 6.8 pounds) greater weight, was associated with a 5% greater prevalence of gout, even after adjusting for serum uric acid (P < 0.001). Conclusion Health care providers should be aware of the elevated burden of gout among both overweight and obese adults, applicable to both women and men, and observed among non-Hispanic whites, non-Hispanic African Americans, and Mexican Americans in the US.