Colchicine Use in Acute Coronary Syndrome: A Systematic Review and Meta-Analysis

Background: This study aimed to assess the efficacy, optimal dosing, and timing of colchicine therapy in reducing major adverse cardiovascular events (MACE), its impact on inflammatory markers, and safety concerns in patients following acute coronary syndrome (ACS) through a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods: A comprehensive search of PubMed, Embase, and the Cochrane Library was conducted in accordance with PRISMA guidelines to identify RCTs comparing colchicine versus placebo or standard treatment in ACS patients. The primary outcome was MACE and secondary outcomes included all-cause and cardiovascular mortality, non-fatal MI, stroke, revascularization, heart failure, CRP/hs-CRP changes, and adverse effects. Fifteen RCTs involving 19,131 patients were analyzed. Results: The benefit of colchicine in reducing MACE risk was marginally significant (RR = 0.79, 95% CI: 0.63-0.99, p = 0.04, I² = 59%). No significant reduction was observed for all-cause mortality, cardiovascular mortality, other cardiovascular outcomes, early initiation of colchicine (≤3 days), or choice of dosage (≤0.5 mg/day vs. >0.5 mg/day). The findings pertaining to the delayed time-to-initiation (>3 days) and changes in CRP or hs-CRP levels were inconclusive. Gastrointestinal side effects, especially diarrhea (RR = 1.76, 95% CI: 1.16-2.66, p = 0.001), were most common. No increase in hematologic events or infections was observed. Conclusions: Colchicine potentially reduces MACE in ACS patients, without evidence of benefit in improving all-cause mortality or other cardiovascular outcomes. Gastrointestinal intolerance is the most common side effect. This result is consistent with current clinical guidelines: a Class IIb recommendation for colchicine use in ACS. There is a need for further high-quality trials to refine patient selection and optimize treatment regimens.