Coronary atheroma regression and adverse cardiac events: A systematic review and meta-regression analysis

Background and aims: The relationship between plaque regression induced by dyslipidemia therapies and occurrence of major adverse cardiovascular events (MACE) is controversial. We performed a systematic review and meta-regression of dyslipidemia therapy studies reporting MACE and intravascular ultrasound (IVUS) measures of change in coronary atheroma. Methods: Prospective studies of dyslipidemia therapies reporting percent atheroma volume (PAV) measured by IVUS and reporting death, myocardial infarction, stroke, unstable angina or transient ischemic attack (MACE) were included. The association between mean change in PAV and MACE was examined using meta-regression via mixed-effects binomial logistic regression models, unadjusted and adjusted for mean age, baseline PAV, baseline low density lipoprotein-cholesterol and study duration. Results: The study included 17 prospective studies published between 2001 and 2018 totaling 6333 patients. Study duration varied from 11 to 104 weeks. Mean change in PAV, across the study arms, ranged from -5.6% to 3.1%. MACE ranged from 0 to 72 events per study arm: 13 study arms (38%) reported no events, 8 (24%) reported 1-2 events and 13 (38%) reported 3 or more events. Meta-regression demonstrated a decline in the odds of MACE associated with reduction in mean PAV: unadjusted odds ratio (OR): 0.78, 95% Confidence Interval (CI): [0.63, 0.96], p= 0.018; adjusted OR: 0.82, 95% CI: [0.70, 0.95], p= 0.011, per 1% decrease in mean PAV. Conclusions: A 1% reduction in mean PAV as induced by dyslipidemia therapies was associated with a 20% reduction in the odds of MACE.