Long-term effect of a dietary intervention with two-healthy dietary approaches on food intake and nutrient density in coronary patients: results from the CORDIOPREV trial

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of disease burden in the world by non-communicable diseases. Nutritional interventions promoting high-quality dietary patterns with low caloric intake value and high nutrient density (ND) could be linked to a better control of CVD risk and recurrence of coronary disease. This study aims to assess the effects of a dietary intervention based on MedDiet or Low-Fat dietary intervention over changes in ND and food intake after 1 and 7 years of follow-up of the CORDIOPREV study. METHODS: We prospectively analyzed the results of the 802 coronary patients randomized to two healthy dietary patterns (MedDiet = 425, Low-Fat Diet = 377) who completed the 7 years of follow-up and had all the dietary data need. Dietary intake information obtained from a validated 137-item Food Frequency Questionnaire was used to calculate 1- and 7-year changes in dietary intake and ND (measured as nutrient intake per 1000 kcal). T test was used to ascertain differences in food intake and ND between groups across follow-up time. Within-subject (dietary allocation group) differences were analyzed with ANOVA repeated measures. RESULTS: From baseline to 7 years of follow-up, significant increases of vegetables, fruits, and whole cereals within groups (p < 0.001) was found. We found a higher increase in dietary intake of certain food groups with MedDiet in comparison with Low-Fat Diet for vegetables (46.1 g/day vs. 18.1 g/day, p < 00.1), fruits (121.3 g/day vs. 72.9 g/day), legumes (4.3 g/day vs. 0.16 g/day) and nuts (7.3 g/day vs. − 3.7 g/day). There was a decrease in energy intake over time in both groups, slightly higher in Low-Fat Diet compared to MedDiet group (− 427.6 kcal/day vs. − 279.8 kcal/day at 1st year, and − 544.6 kcal/day vs. − 215.3 kcal/day after 7 years of follow-up). ND of all the nutrients increased within group across follow-up time, except for Saturated Fatty Acids (SFA), cholesterol and sodium (p < 0.001). CONCLUSIONS: A comprehensive dietary intervention improved quality of diet, reducing total energy intake and increasing the intake of healthy food groups and overall ND after 1 year and maintaining this trend after 7 years of follow-up. Our results reinforce the idea of the participation in trials, enhance nutrition literacy and produces better nutritional outcomes in adult patients with established CVD. CLINICAL TRIAL REGISTRY: The trial was registered in 2009 at ClinicalTrials.gov (number NCT00924937).