LAUSR

Background: While the prevalence of gout and hyperuricemia is believed to be increasing worldwide, there is little population-based data in the US after 2008. We evaluated the prevalence of gout and hyperuricemia in the US National Health and Nutrition Examination survey (NHANES) from 2007-08 to 2015-16, and compared these to previously published estimates to study whether the time-trends continue to show an increase in these rates. Objectives: To study the prevalence of gout and hyperuricemia in the US population from 2007-08 to 2015-16. Methods: We studied adults 20 years and older from the National Health and Nutrition Examination Survey (NHANES), beginning with the continuous NHANES 2-year survey cycles from 2007-08 to 2015-2016. The samples in each cycle were selected using a stratified, multistage, clustered probability sampling design. Persons with gout were identified from the home interview question “Has a doctor or other health professional ever told you that you had gout?” Hyperuricemia was defined as a serum urate level of greater than 6.8 mg/dl (supersaturation levels at physiological temperatures and pH), with alternate definitions of greater than 6.0 mg/dl (defined as the treat-to-target level in some treatment guidelines)(1). All statistical analyses were performed with appropriate survey procedures in SAS v9.4 (SAS Institute Inc., Cary, NC). Survey design variables and weight variables were used to account for the complexity of the NHANES survey design with stratification and clustering. Age-adjusted rates were calculated using 2010 US population numbers (direct standardization). Results: In 2015-16, the overall prevalence of gout among US adults was 3.9%, corresponding to a total affected population of 9.2 million US adults. Gout was significantly more prevalent in men (5.2%) compared to women (2.7%), and the prevalence increased with age. Hyperuricemia (above 6.8 mg/dl) was seen in 14.6% of US population (estimated 32.5 million individuals), and was much more common in men (24.7%) compared to women (5.2%). The alternative definition of hyperuricemia (more than 6.0 mg/dl) was seen in 29.9% of individuals (estimated 66.6 million adults). Both hyperuricemia and gout were less prevalent in Mexican-Americans compared to Whites and African-Americans. No significant trends were identified in the age-adjusted prevalence of gout and hyperuricemia. Statistical comparisons between 2007-08 and 2015-16 age-adjusted rates were not significant. Conclusion: While the age-adjusted prevalence of gout and hyperuricemia has remained unchanged in the most recent decade from 2007-08 to 2015-16, the estimated total number of persons with self-reported gout has gone up from 8.3 million to 9.2 million, reflecting the growth and increased aging of the US population. The age-adjusted prevalence of hyperuricemia has declined slightly but the total number of affected individuals is virtually identical (32.5 million in 2015-16 compared to 32.1 million in 2007-08). While the stabilization of gout and hyperuricemia prevalence rates is encouraging, our study highlights the still considerable burden of gout and hyperuricemia in the increasingly aging US population. Reference [1] Ruoff G, Edwards NL. Overview of Serum Uric Acid Treatment Targets in Gout: Why Less Than 6 mg/dL? Postgraduate medicine. Sep 2016;128(7):706-715. Disclosure of Interests: Gurkirpal Singh Shareholder of: Merck, Pfizer, Grant/research support from: Horizon, Acorda, UCB, Consultant for: Horizon, Acorda, Sancilio, Unipharm, Bharathi Lingala: None declared, Alka Mithal: None declared