Long-term dietary adherence and changes in dietary intake in coronary patients after intervention with a Mediterranean diet or a low-fat diet: the CORDIOPREV randomized trial

Adherence to a healthy dietary pattern positively influences clinical outcomes in cardiovascular prevention, but long-term adherence is difficult to maintain. We evaluated 5-year changes in dietary habits, adherence achieved, and its maintenance in a cohort of coronary patients from the CORDIOPREV study. 1002 coronary patients were randomized to a Mediterranean diet (n = 502) or a low-fat diet (n = 500) and received individual-group-telephone visits and personalized dietary advice. A validated food-frequency questionnaire, a 14-point Mediterranean diet adherence screener, and a 9-point low-fat diet adherence score were used. Dietary adherence was categorized into Low, Medium, and High Adherence. Changes in nutrient intake, food consumption, and adherence were analyzed on a yearly basis. The maintenance of long-term dietary adherence was evaluated using data after the first year and fifth year. From baseline to 5 years, significant increases were observed in overall dietary adherence (Mediterranean diet from 8.9 to 11.4; low-fat diet from 3.9 to 7.1) and in the percentage of patients considered High Adherence (Mediterranean diet from 41 to 89%; low-fat diet from 4 to 67%). When we evaluated the maintenance of adherence, patients considered Low and Medium Adherence at 1 year increased their adherence at the 5 years with both diets and patients considered High Adherence maintained their adherence with a Mediterranean diet, but decreased their adherence with a low-fat diet. A comprehensive dietary intervention results in an overall long-term improvement and maintenance of adherence to the Mediterranean and low-fat diets. In our population, the Mediterranean diet group achieved a high level of adherence in the short term which was maintained in the long term.