Impact of a Mediterranean Diet on Cardiovascular Disease Risk Factors

This approved and funded research project is part of a larger project titled "Algarve Active Ageing - Cardiac and Osteoarthritis Rehabilitation (A3-COR): personalized exercise protocol in the rehabilitation after acute myocardial infarction or at risk of cardiovascular disease and knee osteoarthritis, a multicenter clinical intervention study".

The main objective of this work is to quantify the effect of a nutritional and physical activity intervention in improving important risk factors for cardiovascular disease, such as body weight, body composition, and waist circumference.

Cardiovascular diseases are the leading cause of death worldwide and one of the main contributors to diminished quality of life. It is estimated that in the year 2019, approximately 17.9 million individuals died due to this non-communicable disease, accounting for 32% of all global deaths. It is considered that CVDs result from the interaction between genetic predisposition (non-modifiable risk factors) and environmental influences (modifiable risk factors). Environmental factors prevail over others and often lead to negative outcomes through the adoption of poor lifestyles, such as imbalanced nutrition, physical inactivity, smoking, and alcohol habits. These are considered risk factors with direct effects on the pathogenesis of CVDs, and indirectly contribute to increasing the risk for predisposition to chronic diseases such as hypertension, dyslipidemia, overweight, obesity, and diabetes mellitus.

Currently, scientific literature has demonstrated the importance of diet in preventing CVDs and how it can minimize their risk factors. The Dietary Approaches to Stop Hypertension, Mediterranean dietary pattern, vegetarian diet, EAT-Lancet diet, and other dietary strategies have been published in various scientific journals.

Parallel to health, another topic that has gained prominence in the scientific community is environmental degradation derived from current food production. With the projected population growth until 2050, reaching 10 billion, the effects of food production on greenhouse gas emissions, nitrogen and phosphorus pollution, biodiversity loss, and water and land use are predicted to reach such high values that they will lead to the destabilization of the Earth system.

Considering that diet holds both environmental value and promotes cardiovascular health, this study aims to explore more sustainable and health-promoting dietary adaptations. This intervention will be based on principles of the Mediterranean diet, integrating higher consumption of plant sources compared to other mentioned patterns, and also leveraging the benefits of chronobiology, which are important for weight and adiposity control.

RECRUITMENT PLAN Participants will be recruited from the Algarve Active Ageing - Cardiac and Osteoarthritis Rehabilitation (A3-COR) project, carried out under the Algarve Biomedical Center - Research Institute. After the participants are integrated into the A3-COR project, those who meet the requirement of never having suffered from AMI but have high cardiovascular disease risk criteria according to the SCORE2 or SCORE2 O.P. algorithm will be contacted by phone. At this point, the objective of the nutritional intervention and the necessary conditions for participation will be explained (assessment of the remaining inclusion and exclusion criteria). After verifying these criteria, they will be invited to voluntarily participate in the present study. Those who accept to join the study will be contacted again to schedule the initial evaluation, and must sign the informed consent form prior to that.

PARTICIPANTS ALLOCATION Participants of the A3-COR control group who agree to participate in the present study (RATE) undergo an initial evaluation, forming the group (NO DIET + NO EXERCISE). These participants were randomly selected using new computer-generated numbers until a sample of 30-35 participants was reached from the total of 74 participants in this group. Participants from the Exercise Group of the A3-COR project who express interest in participating in the RATE project undergo randomization by numbers into one of two groups: the (EXERCISE + NO DIET n=30-35) group, which continues the exercise sessions as planned in the A3-COR project, and the (EXERCISE + DIET n=30-35) group, which, in addition to the exercise sessions, also receives nutritional guidance. This randomization is conducted among the 74 participants in the Exercise Group of the A3-COR project.

STATISTICS The statistical analysis will be performed using the Statistical Package for the Social Sciences (SPSS), version 27.0. All normally distributed numerical variables will be presented in the format of mean ± standard deviation. The normality of the variables will be tested using the Kolmogorov-Smirnov test. Differences between groups will be determined using paired t-tests. Repeated measures ANOVA will be used to detect changes between and within groups. Results will be considered statistically significant for p\<0.05.

Eligibility Criteria:
Inclusion Criteria:

* Age equal to or greater than 50 years
* Individuals meeting the criteria for high cardiovascular disease risk in the SCORE2 or SCORE2 O.P algorithm
* Autonomy in activities of daily living
* Provide informed and clarified consent

Exclusion Criteria:

* Occurrence of Acute Myocardial Infarction (AMI)
* To receive nutritional counseling from a registered dietitian
* To follow a vegetarian or strict vegetarian dietary pattern
* To take nutritional supplementation