The 3-Year Incidence of Gout in Elderly Patients with CKD.

BACKGROUND AND OBJECTIVES: The risk of gout across CKD stages is not well described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We performed a retrospective cohort study using linked health care databases from Ontario, Canada from 2002 to 2010. The primary outcome was the 3-year cumulative incidence of gout, on the basis of diagnostic codes. We presented our results by level of kidney function (eGFR≥90 ml/min per 1.73 m2 , 60-89, 45-59, 30-44, 15-29, and chronic dialysis) and by sex. Additional analyses examined the risk of gout adjusting for clinical characteristics, incidence of gout defined by the receipt of allopurinol or colchicine, and gout risk in a subpopulation stratified by the level of eGFR and albuminuria.

RESULTS: Of the 282,925 adults aged ≥66 years, the mean age was 75 years and 57.9% were women. The 3-year cumulative incidence of gout was higher in older adults with a lower level of eGFR. In women, the 3-year cumulative incidence of gout was 0.6%, 0.7%, 1.3%, 2.2%, and 3.4%, and in men the values were 0.8%, 1.2%, 2.5%, 3.7%, and 4.6%, respectively. However, patients on chronic dialysis had a lower 3-year cumulative incidence of gout (women 2.0%, men 2.9%) than those with more moderate reductions in kidney function ( i.e. , eGFR 15-44 ml/min per 1.73 m2 ). The association between a greater loss of kidney function and a higher risk of diagnosed gout was also evident after adjustment for clinical characteristics and in all additional analyses.

CONCLUSIONS: Patients with a lower level of eGFR had a higher 3-year cumulative incidence of gout, with the exception of patients receiving dialysis. Results can be used for risk stratification.