Dietary carbohydrate quality, fibre-rich food intake, and left ventricular structure and function: the CARDIA study.

Identifying lifestyle risk factors related to abnormal cardiac phenotypes, including structure and function, will be essential to prevent or slow down the progression to heart failure. Little is known about intakes of macronutrients and food groups, particularly carbohydrate (CHO) quality and fibre-rich foods, relative to cardiac phenotypes. Therefore, the association between CHO quality and cardiac phenotypes was examined in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Trained interviewers conducted the CARDIA Diet History to gather dietary intake at exam years 0, 7, and 20. Cardiac phenotype measures were collected at exam years 25 and 30 via echocardiography. Linear mixed effects regression models were used to evaluate the association of CHO quality and fibre-rich food score averaged across years 0, 7, and 20 with cardiac phenotype measures at years 25 and 30. Among the 3171 CARDIA participants, quartiles of CHO quality (defined using CHO:fibre ratio) were favourably associated with left ventricular (LV) mass index (Ptrend < .001) and global longitudinal strain (Ptrend < .001) after adjusting for demographic and lifestyle factors. Similarly, quartiles of fibre-rich food score (created based on daily intakes of whole grains, fruit, vegetables, nuts, and legumes) were favourably associated with LV mass index (Ptrend < .001), LV ejection fraction (Ptrend = .008), global longitudinal strain (Ptrend < .001), E/e' ratio (Ptrend = .02), and left atrial volume index (Ptrend = .02). Cardiac phenotype effect sizes between 10% and 26% of their respective standard deviations. Higher quality of CHO and intake of fibre-rich foods were favourably associated with LV structure and function.