Colchicine in acute coronary syndromes: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND: Acute coronary syndrome (ACS) is a global leading cause of morbidity, with residual inflammation contributing to recurrent events. Colchicine has been proposed as an adjunct therapy, but its efficacy remains uncertain. METHODS: We performed a systematic review and meta-analysis. PubMed, Embase and Cochrane databases were searched for randomised controlled trials (RCTs) data comparing colchicine versus placebo in ACS. Risk ratio (RR) and mean difference with 95% CIs were computed for binary and continuous outcomes, respectively. Primary outcomes were adverse cardiovascular events (ACEs), mortality and safety. Random-effects models were used for pooled estimates. RESULTS: Seventeen RCTs comprising 14 794 patients were included, of whom 7390 (50%) were randomised to colchicine. The mean patient age across the studies ranged from 54 to 63 years, in a follow-up period ranging from 5 days to 12 months. Colchicine reduced the incidence of recurrent ACS (RR 0.41, 95% CI 0.19 to 0.92; p=0.03; I²=55%) and unstable angina (RR 0.27, 95% CI 0.11 to 0.63; p<0.01; I²=0%). No meaningful differences were observed in all-cause mortality (RR 0.95, 95% CI 0.79 to 1.14; I²=12%), cardiovascular death (RR 1.03, 95% CI 0.82 to 1.30; I²=0%) or ACE (RR 0.77, 95% CI 0.59 to 1.01; p=0.05; I²=58%). Subgroup analyses suggested a dose-dependent effect, with 0.5 mg/day potentially reducing ACE (RR 0.63, 95% CI 0.45 to 0.88; I²=41%), but higher doses increasing gastrointestinal symptoms. CONCLUSION: Low-dose colchicine may reduce recurrent ischaemic events in ACS, but evidence remains uncertain due to heterogeneity and limited long-term data. Safety and efficacy in women and optimal dosing require further investigation. TRIAL REGISTRATION NUMBER: CRD42024627348.