Gout and chronic pain in older adults: a Medicare claims study.

Abstract

To assess if gout is associated with a higher risk of incident chronic pain. This study used the 2006-2012 Medicare claims data. We used multivariable-adjusted Cox regression analyses to examine the association of pre-existing diagnosis of gout with incident (new) diagnosis of chronic pain, adjusting for demographics, medical comorbidity, and use of common medications for cardiovascular disease and gout. Sensitivity analyses substituted Charlson-Romano score with a categorical variable or each Charlson-Romano comorbidity. There were 1,321,521 eligible people, of whom 424,518 developed incident chronic pain. Crude incidence rates of chronic pain were as follows: gout, 158.1 per 1000 person-years and no gout, 64.5 per 1000 person-years. In multivariable-adjusted Cox regression analyses, gout was associated with higher hazard ratio of chronic pain, 2.02 (95% CI, 1.98, 2.05), confirmed in sensitivity analyses 1.96 (95% CI, 1.93, 1.99) (model 2) and 1.77 (95% CI, 1.74, 1.80) (model 3). No meaningful differences were found by gender and race in subgroup analyses; slightly lower hazard of chronic pain with gout was seen in oldest people. Use of allopurinol or febuxostat was associated with lower risk of chronic pain, 0.79 (95% CI, 0.77, 0.82; model 1) and 0.72 (95% CI, 0.56, 0.92; model 1). Gout was associated with a doubling of the risk of chronic pain and gout treatments with reduction in the risk. Efforts must be made to optimize gout control, so that chronic pain can be avoided as a long-term sequalae of gout and when present, treated early and appropriately. Key points • Gout was associated with twofold higher risk of incident (or new) diagnosis of chronic pain. • Gout treatments were associated with a lower chronic pain risk. • Increased risk of chronic pain with gout was similar across age, race, and sex. • Studies should examine if optimal gout control with treat-to-target approach can reduce the risk of chronic pain in people with gout.