An updated systematic review and meta-analysis of randomised controlled trials on the effects of urate-lowering therapy initiation during a gout flare.

Background: There is uncertainty about the optimal time to start urate-lowering therapy (ULT) in the setting of a gout flare. The aim was to perform a systematic review and meta-analysis of randomised controlled trials (RCTs) assessing the effects of ULT initiation during a gout flare.

Methods: This systematic review was conducted in accordance with PRISMA methodology. MEDLINE, EMBASE and The Cochrane Library were searched for studies published between database inception to 1 March 2023. RCTs published in English that examined ULT initiation during a gout flare in adults ≥18 years were included. The quality of included studies was assessed using the revised Cochrane Risk of Bias tool 2.0. Data were extracted for the following outcomes: patient-rated pain score, duration of gout flare, recurrent gout flares, time to achieve target serum urate, adherence to ULT, patient satisfaction with treatment and adverse events. Meta-analyses were performed using Review Manager v5.4. This study is registered on PROSPERO, number CRD42023404680.

Results: A total of 972 studies were identified and of these, six RCTs met the criteria for inclusion in the analysis. Three studies were assessed as having high risk of bias, one study as having some concerns, and two studies as having low risk of bias. In total, there were 445 pooled participants; 226 participants randomised to early initiation of ULT and 219 to placebo or delayed initiation of ULT. Allopurinol was used in three studies, febuxostat in two studies and probenecid in one study. Few participants (n = 62, 13.9 %) had tophaceous gout. Participants with renal impairment were excluded from most studies. There were no differences in patient-rated pain scores at baseline, days 3-4, days 7-8, day 10 or days 14-15 (p ≥ 0.42). Additionally, there was no significant difference in time to resolution of gout flare (standardised mean difference 0.77 days; 95 % CI -0.26 to 1.79; p = 0.14) or the risk of recurrent gout flare in the subsequent 28 to 30 days (RR 1.06; 95 % CI 0.59 to 1.92; p = 0.84). Adverse events were similar between groups. The included studies did not report time to achieve target serum urate, long-term adherence to ULT, or patient satisfaction with treatment.

Conclusion: There appears to be no evidence for harm or for benefit to initiating ULT during a gout flare. These findings have limited applicability to patients with tophaceous gout, or those with renal impairment.