Association of the Mediterranean Diet, Physical Activity and Related Lifestyle Factors on the Mortality and Major Adverse Cardiovascular Events in Patients with Coronary Heart Disease: A Systematic Review and Meta-Analysis

Introduction: Evidence linking Mediterranean dietary patterns and physical activity to mortality and major adverse cardiovascular events (MACEs) after coronary heart disease (CHD) diagnosis remains inconclusive. Methods: The search covered PubMed, MEDLINE, Scopus, Embase, and CENTRAL from January 2015 through 15 June 2026. Comparable hazard ratios (HRs) were pooled using random-effects models; non-equivalent estimands were reported separately. Risk of bias was evaluated with design-appropriate tools and certainty with GRADE. Results: The 40 reports represented 34 data sources and at least 260,354 unique patients, comprising six randomized trials, 30 observational reports, and four comparative nonrandomized studies. In one randomized comparison of Mediterranean and low-fat diets, the HR for MACE was 0.72 (95% CI 0.54 to 0.96; moderate certainty). Observational findings supported inverse associations of closer dietary adherence with all-cause mortality (HR 0.74, 95% CI 0.60 to 0.90; I2 = 44%) and MACE, whereas cardiovascular mortality remained uncertain. HRs for maintained or continued physical activity relative to persistent inactivity were 0.64 for all-cause mortality (95% CI 0.55 to 0.74; I2 = 29%) and 0.42 for cardiovascular mortality (95% CI 0.28 to 0.64; I2 = 72%). MACE findings for diet adherence and habitual physical activity generally favored lower risk. Randomized evidence on exercise or combined dietary and activity programs was sparse. Conclusions: Greater Mediterranean diet adherence and habitual physical activity were associated with more favorable CHD outcomes. Standardized, adequately powered trials are needed, especially for exercise and combined strategies.