Portfolio Diet Score and Risk of Cardiovascular Disease: Findings From 3 Prospective Cohort Studies

BACKGROUND: The plant-based Portfolio dietary pattern includes recognized cholesterol-lowering foods (ie, plant protein, nuts, viscous fiber, phytosterols, and plant monounsaturated fats) shown to improve several cardiovascular disease (CVD) risk factors in randomized controlled trials. However, there is limited evidence on the role of long-term adherence to the diet and CVD risk. The primary objective was to examine the relationship between the Portfolio Diet Score (PDS) and the risk of total CVD, coronary heart disease (CHD), and stroke. METHODS: We prospectively followed 73 924 women in the Nurses’ Health Study (1984–2016), 92 346 women in the Nurses’ Health Study II (1991–2017), and 43 970 men in the Health Professionals Follow-up Study (1986–2016) without CVD or cancer at baseline. Diet was assessed using validated food frequency questionnaires at baseline and every 4 years using a PDS that positively ranks plant protein (legumes), nuts and seeds, viscous fiber sources, phytosterols (mg/day), and plant monounsaturated fat sources, and negatively ranks foods high in saturated fat and cholesterol. RESULTS: During up to 30 years of follow-up, 16 917 incident CVD cases, including 10 666 CHD cases and 6473 strokes, were documented. After multivariable adjustment for lifestyle factors and a modified Alternate Healthy Eating Index (excluding overlapping components), comparing the highest with the lowest quintile, participants with a higher PDS had a lower risk of total CVD (pooled hazard ratio [HR], 0.86 [95% CI, 0.81–0.92]; P trend <0.001), CHD (pooled HR, 0.86 [95% CI, 0.80–0.93]; P trend =0.0001), and stroke (pooled HR, 0.86 [95% CI, 0.78–0.95]; P trend =0.0003). In addition, a 25-percentile higher PDS was associated with a lower risk of total CVD (pooled HR, 0.92 [95% CI, 0.89–0.95]), CHD (pooled HR, 0.92 [95% CI, 0.88–0.95]), and stroke (pooled HR, 0.92 [95% CI, 0.87–0.96]). Results remained consistent across sensitivity and most subgroup analyses, and there was no evidence of departure from linearity for CVD, CHD, or stroke. In a subset of participants, a higher PDS was associated with a more favorable blood lipid and inflammatory profile. CONCLUSIONS: The PDS was associated with a lower risk of CVD, including CHD and stroke, and a more favorable blood lipid and inflammatory profile, in 3 large prospective cohorts.