Abstract Background Recent trials have demonstrated that low-dose colchicine can reduce the risk of cardiovascular events in patients with coronary artery disease.(1) However, discontinuation rates of trial medication ranged from 10.1% to 25.9%, potentially reducing its effectiveness.(2,3) The role of side effects in this remains unclear. Purpose To evaluate the incidence and type of side effects that led to premature discontinuation of trial medication in participants with chronic coronary syndromes in the Low-Dose Colchicine 2 (LoDoCo2) trial. Methods We evaluated the incidence of side effects leading to discontinuation of trial medication in the LoDoCo2 trial, which consisted of a 30-day run-in phase during which all participants received colchicine 0.5 mg once daily, followed by randomization to colchicine or placebo. Side effects of colchicine were evaluated at the end of the run-in phase (early side effects, within 30 days) and during the randomization phase (late side effects, median follow-up: 29.5 months). Cumulative incidences of side effects are presented using Kaplan-Meier curves and compared by treatment arm using Cox proportional hazards modelling. Results Trial medication was discontinued by 997 of 6519 (15.3%) participants during the run-in phase, of whom 618 (9.5%) participants reported early side effects. After randomization, 273 (10.0%) participants in the colchicine group and 281 (10.3%) participants in the placebo group discontinued trial medication. Among those who stopped trial medication, 114 participants in the colchicine group reported side effects (4.2%, 1.6 events per 100 person-years), compared to 120 participants in the placebo group (4.4%, 1.7 events per 100 person-years, hazard ratio HR 0.95, 95% confidence interval CI 0.73–1.22). Gastrointestinal upset and myalgia were the most common side effects (2.0% and 1.2% in the colchicine group and 1.7% and 1.6% in the placebo group, respectively), with no differences between treatment groups. Female sex was independently associated with an increased risk of both early- and late side effects, irrespective of treatment allocation. Statin use was independently associated with lower rates of late side effects, with no difference between colchicine and placebo. Conclusion After the open-label run-in phase, the incidence of late side effects in participants with chronic coronary syndromes did not differ between patients randomized to low-dose colchicine or placebo.
Jannink et al. (Sat,) studied this question.