Patients with gout initiating urate-lowering therapy who were prescribed colchicine for flare prophylaxis had a lower risk of cardiovascular events compared with those who did not receive prophylaxis, according to a recent retrospective cohort study.
Published in The Lancet Rheumatology, researchers analyzed 99,800 patients with gout who started ULT between 1997 and 2021. Of these, 16,028 (16.1%) received colchicine prophylaxis for at least 21 days, while 83,772 (83.9%) did not. Researchers used data from the Clinical Practice Research Datalink Aurum, an English primary-care database linked to hospitalization and mortality records.
The weighted incidence rate of cardiovascular events—including fatal and non-fatal myocardial infarction and stroke—was 28.8 per 1,000 person-years (95% CI, 25.2-33.2) in the colchicine group, compared with 35.3 per 1,000 person-years (95% CI, 33.0-37.9) in the no-prophylaxis group. The weighted hazard ratio was 0.82 (95% CI, 0.69-0.94), indicating an 18% relative risk reduction. The weighted risk difference was -6.5 events per 1,000 person-years (95% CI, -9.4 to -3.6), with a number needed to treat of 154 (95% CI, 94 to 425).
"In patients with gout initiating urate-lowering therapy, the risk of cardiovascular events was reduced in those prescribed colchicine prophylaxis compared with no prophylaxis," said Edoardo Cipolletta from the University of Nottingham. "These findings provide an additional argument for using colchicine for gout flare prophylaxis."
The risk of first-ever cardiovascular events was also lower in the colchicine group (HR, 0.80; 95% CI, 0.62-0.97), though no significant differences were observed for fatal cardiovascular events, myocardial infarction, or stroke as separate outcomes. As expected, diarrhea was more common in the colchicine group, particularly in the per-protocol analysis.
Patients receiving colchicine prophylaxis had a mean age of 63.5 years, and 76.8% were male. The majority (85.1%) were White. Baseline cardiovascular risk factors, such as arterial hypertension (57.2%), hypercholesterolemia (11.1%), and diabetes (16.3%), were similar between groups after propensity score weighting.
Colchicine was prescribed at a mean daily dose of 0.97 mg for a mean duration of 47.3 days. The authors noted that only 16.1% of patients received gout flare prophylaxis, despite international guidelines recommending colchicine during the first 3-6 months of ULT initiation.
Although the study was observational, it used robust statistical methods, including inverse probability of censoring weighting, to balance covariates across groups. The E-value analysis indicated that an unmeasured confounder would need to be associated with both cardiovascular events and flare prophylaxis by hazard ratios of 1.74 and 1.85 to nullify the findings in the intention-to-treat and per-protocol analyses, respectively.
The authors acknowledged limitations, including potential residual confounding and the inability to verify medication adherence beyond prescription records.
The findings align with prior research on colchicine's cardiovascular benefits, but randomized controlled trials are needed to confirm a causal relationship. The study was funded by the Foundation for Research in Rheumatology. Disclosures can be found in the study.
