Allopurinol use, dose escalation do not increase mortality in gout patients with CKD

In patients with gout and concurrent chronic kidney disease (CKD), the risk of mortality does not seem to increase with initiation of allopurinol, achieving target serum urate (SU) level with allopurinol, or treatment dose escalation, a study has shown.

A team of investigators conducted this cohort study to examine the association of allopurinol initiation, allopurinol dose escalation, and achieving target SU level after treatment initiation with all-cause mortality in patients with both gout and CKD.

Using the Health Improvement Network UK primary care database (2000 to 2019), the investigators identified patients aged ≥40 years who had gout and concurrent moderate-to-severe CKD. They assessed the relation between allopurinol initiation and all-cause mortality over 5-year follow-up in propensity score (PS)–matched cohorts.

Analysis of hypothetical trials were also emulated: achieving target SU level (<0.36 mmol/L) vs not achieving target SU level and dose escalation vs no dose escalation for mortality over 5-year follow-up in allopurinol initiators.

Mortality was 4.9 per 100 person-years in 5,277 allopurinol initiators and 5.8 per 100 person-years in 5,277 PS-matched noninitiators (hazard ratio [HR], 0.85, 95 percent confidence interval [CI], 0.77‒0.93).

In the target trial emulation analysis, mortality HR was 0.87 (95 percent CI, 0.75‒1.01) for the achieving target SU level group compared with the not achieving target SU level group and 0.88 (95 percent CI, 0.73‒1.07) for allopurinol in the dose escalation group vs the no dose escalation group.

Of note, the study was limited by possible residual confounding, according to the investigators.