UC San Diego

Objective

The interleukin-1 (IL-1) receptor antagonist anakinra is an effective, off-label option in acute gout flares, when conventional therapy options are narrowed. We performed a retrospective, randomized, case-controlled study to gain clinical insight on baseline factors for gout patients most likely to receive anakinra, and ultimate mortality of those who received anakinra.

Methods

Of 1451 gout patients seen between January 2003 and January 2015 in a Veterans Affairs (VA) rheumatology group practice, under stringent managed care principles, 13 (100% male), who received anakinra at least once for flares, were compared with 1:4 age- and sex-matched gout controls. Each patient's first rheumatology encounter was studied by factor analysis for variables associated with later anakinra.

Results

At baseline, patients that received anakinra had higher urate burden (palpable tophi [10/13] vs controls [16/52], P = .003), serum urate ([10.6 mg/dL] vs controls [7.6 mg/dL], P < .0001), and East Asian descent ([7/13] vs [16/52], P = .041). The anakinra group had higher ultimate all-cause mortality ([6/13] vs controls [7/52], relative risk [RR] = 3.43, 95% confidence interval [CI] = 1.39-8.48, P = .0076). Factor analysis showed baseline visit palpable tophus and statin use to be most strongly associated with later anakinra use. Increased mortality of anakinra users, as per a factorial analysis, was linked more strongly to comorbidities than to anakinra.

Conclusions

At baseline rheumatology gout encounter, higher urate, palpable tophi, statin prescription, and East Asian descent were associated with later anakinra use for flares. Mortality was more closely associated to the presence of comorbidities at baseline rheumatology visit than to anakinra prescription.