Methods: We studied the incidence and prevalence of gout in white older adults using the Atherosclerosis Risk in Communities Study, a prospective US population-based cohort study of middle-aged adults enrolled between 1987-1989 with ongoing follow-up. A genetic urate score (GUS) was formed from common urate-associated single nucleotide polymorphisms for eight genes. The adjusted hazard ratio (HR) and 95% confidence intervals (CI) of incident gout by traditional and genetic risk factors in middle age were estimated using a Cox Proportional Hazards model.

Results: Of the 9,526 participants, 46.2% were male and the mean (SD) age at cohort enrollment was 54.0 (5.7). The overall prevalence of gout was 8.9%; 31.9% of those with a history of gout reported a physician diagnosis of this inflammatory arthritis at age 65 or older. By age 65 the prevalence of gout was 9.0% for men and 3.3% for women, conditioned on survival to age 65. The cumulative incidence from middle age to age 65 was 8.6% in men and 2.5% in women as well as 8.0% for those in the 4^th quartile of GUS, 5.0% for those in the 3^rd quartile, 3.8% for those in the 2^nd quartile and 3.3% for those in the 1^st quartile, conditioned on survival to age 65 (Figure). In middle age, increased adiposity, beer intake, protein intake, smoking status, hypertension, diuretic use, and kidney function (but not sex) were associated with an increased risk of gout in older age. In addition, high genetic risk (100 μmol/L increase in GUS) was associated with a 3.29-fold (95% CI: 1.63, 6.63) increased risk of gout in older age.

Conclusion: In this US population-based cohort, traditional risk factors that were present in middle-age were associated with the development of gout in older age.

Figure: Cumulative incidence of gout by quartile of genetic urate score. The incidence of gout for participants of ARIC was estimated using a Kaplan-Meier approach. All cumulative incidences (%) should be interpreted as the percentage of participants with gout, conditioned on survival to that age. The genetic urate score is measured in μmol/L. Quartile 1 of the genetic urate score ranges from -59.1 to -13.1; quartile 2 from -13.2 to 0.3; quartile 3 from -.4 to 12.0 and quartile 4 from 12.1 to 60.8.