Mortality in Patients With Gout Treated With Allopurinol: A Systematic Review and Meta-Analysis.

Objective: Urate-lowering therapy (predominantly allopurinol) is highly effective as a treatment for gout, but its wider long-term effects remain unclear. This systematic review and meta-analysis aimed to ascertain the association between mortality and the use of allopurinol in patients with gout.

Method: Medline, Embase, CINAHL, and the Cochrane Library were searched from inception to August 2018. Articles eligible for inclusion used a cohort design and examined cardiovascular or all-cause mortality in patients diagnosed with gout and prescribed allopurinol. Information on study characteristics, design, sample size, and mortality risk estimates were extracted. Article quality was assessed using the Newcastle-Ottawa Scale. Included articles were described in a narrative synthesis and, where possible, risk estimate data were pooled.

Results: Four articles reported a hazard ratio (HR) risk estimate for all-cause mortality in patients with gout using allopurinol, and 2 of these also reported cardiovascular mortality. Two articles found allopurinol to be protective in patients with gout, 1 found no statistically significant association, and 1 found no statistically significant effect of escalation of allopurinol dosage on all-cause or cardiovascular-related mortality. Data pooling was possible for all-cause mortality and found no association between allopurinol use in patients with gout and all-cause mortality compared to patients with gout not using allopurinol (adjusted HR 0.80 [95% confidence interval 0.60-1.05]).

Conclusion: There was no significant association between all-cause mortality and allopurinol use in people with gout. However, the number of included studies was small, suggesting that further studies are needed.