More Weight, More Gout

Gout rates higher among those with higher BMI

(RxWiki News) As rates of obesity continue to increase, more and more Americans are developing diseases tied to their excess weight. According to a recent study, gout appears to be one of those diseases.

Researchers set out to study the relationship between gout and body mass index (BMI) - a measure of body fat using height and weight.

Results showed that overweight and obese adults had higher rates of gout than their normal weight counterparts. As BMI increased so, too, did rates of gout.

According to the authors, "Healthcare providers should be aware of the elevated burden of gout among both overweight and obese adults."

"Control your weight to lower risk of gout."

The study was conducted by Allan Gelber, MD, PhD, MPH, and fellow researchers at Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland.

The researchers used information from the National Health and Nutrition Examination Survey (NHANES) in 1988 to 1994 and 2007 to 2010. The study included 16,521 adults in the 1988 to 1994 survey and 11,589 adults in the 2007 to 2010 survey who responded to questions about gout status and had their BMI measured.

Participants were split into groups according to BMI: underweight (BMI of 18.5 or less), normal weight (BMI of 18.5 to 24.9), overweight (BMI of 25 to 29.9), obesity class I (BMI of 30 to 34.9) and obesity classes II or III (BMI of 35 or more).

Results showed gout rates of:

  • 1 to 2 percent among normal weight participants
  • 3 percent among overweight participants
  • 4 to 5 percent with class I obesity
  • 5 to 7 percent with class II or class III obesity

The ratio of gout rates between participants with the highest BMI and those with normal BMI was 2.46 in 1988 to 1994 and 2.21 in 2007 to 2010.

In both survey periods, for an average American adult standing 5 feet 9 inches, a one unit increase in BMI (about 6.8 pounds) was associated with a 5 percent greater rate of gout.

Gout is a type of arthritis that happens when uric acid builds up in the blood. This buildup can cause joints to become inflamed.

According to the authors, obesity is often though to increase gout risk by boosting levels of uric acid in the blood. In addition, obesity has been shown to increase molecules that contribute to inflammation.

The current study further showed that excess weight and obesity can impact the rate of gout, even after the researchers accounted for differences in uric acid levels.

"In conclusion, successive categories of BMI are associated in a dose-response fashion with a higher prevalence of gout," the authors wrote.

In other words, for every level increase in BMI, there was a corresponding increase in gout rates.

The associations between BMI and gout were "observed among women and men, as well as among non-Hispanic whites, non-Hispanic African Americans and Mexican Americans," the authors wrote.

"Healthcare providers treating obese or even overweight patients should be cognizant of the elevated burden of gout among these segments of the US population," they concluded.

The study was published December 27 in Arthritis Care & Research. The work was funded by the National Institutes of Health and the Donald B. and Dorothy Stabler Foundation. Information on potential conflicts of interest was not available.

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Review Date: 
January 17, 2013
Last Updated:
January 30, 2013