may 2024

Long-term impact of mediterranean diet on cardiovascular disease prevention: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND: Dietary modification plays a pivotal role in the prevention of cardiovascular disease (CVD), with particular emphasis on the potential benefits associated with adopting a Mediterranean diet (MedDiet). Numerous observational studies have explored the impact of the MedDiet on CVD prevention, addressing both primary and secondary prevention. However, a substantial portion of the primary evidence comes from specific Randomized Controlled Trials (RCTs), such as the Lyon Diet Heart Study, the Indo-Mediterranean Diet Heart Study, the PREDIMEDThe PREDIMED study is one of the few randomized controlled trials about the Mediterranean Diet. More... Study, and the recent CORDIOPREV Study. To provide a comprehensive assessment of the long-term clinical effects, we conducted a meta-analysis, systematically synthesizing findings from RCTs to better understand the preventive impact of MedDiet on cardiovascular health.

METHODS: We searched for RCTs exploring the efficacy of MedDiet on CVD prevention from inception until January 2024, utilizing databases such as MEDLINE (via PubMed), Google Scholar, the CochraneCochrane is a global independent network of health practitioners researchers patient advocates and o... Library,, and the ScienceDirect portal. Statistical analysis used RevMan 5.4 with a random-effects model, presenting dichotomous outcomes as odds ratios (OR) with a 95 % confidence interval (CI) and assessing heterogeneity using the I(2) test.

RESULTS: Our analysis incorporated four RCTs involving a total of 10,054 participants, with an average age of 57 years and a mean follow-up duration ranging from 2 to 7 years. In our pooled analysis, the composite endpoint of major adverse cardiovascular events (MACE) demonstrated a statistically significant reduction in incidence in participants on MedDiet versus control diet with an OR of 0.52 (95 % CI: 0.32 to 0.84, p = 0.008; I(2) = 87 %). Additionally, our study revealed a notable decrease in the incidence of cardiovascular events, both myocardial infarction (MI) and stroke in the the MedDiet group, with an OR of 0.62 (95 % CI: 0.41 to 0.92, p = 0.02; I(2) = 56 %) and 0.63 (95 % CI: 0.48 to 0.87, p = 0.002; I(2) = 0 %), respectively. However, no statistically significant change in the rate of revascularization was observed, with an OR of 0.74 (95 % CI: 0.30 to 1.27, p = 0.06; I(2) = 16 %). Concerning mortality rates, MedDiet significantly reduced the risk of cardiovascular death with an OR of 0.54 (95 % CI: 0.31 to 0.94, p = 0.03; I(2) = 55 %), while no significant change was noted in all-cause mortality, with an OR of 0.77 (95 % CI: 0.51 to 1.15, p = 0.20; I(2) = 58 %).

CONCLUSION: MedDiet serves as an effective intervention for both primary and secondary prevention of CVD, demonstrating a substantial and long-term impact in reducing the incidence of MACE, MI, stroke, and cardiovascular-related mortality while showing no observed effect on all-cause mortality. Nevertheless, it is essential to acknowledge the current limitations in available clinical trial evidence, emphasizing the need for additional trials to substantiate and strengthen these findings.

Additional Info

  • Authors

    Sebastian S. A.; Padda I.; Johal G.
  • Issue

    Periodical: Curr Probl Cardiol - Volume: 49 - Number: 5 - Edition: 20240301
  • Published Date

    may 2024