Healthful plant-based diet and incidence of hypertension in Brazilian adults: A six-year follow-up of the CUME study

Background

Studies demonstrate that consuming plant-based diets has beneficial effects on several health outcomes. However, the evaluation of the healthiness of plant-based diets and the incidence of hypertension has still been little explored in the literature. Objectives: Thus, this study aimed to evaluate the association between plant-based diet indices and the incidence of hypertension in Brazilian adults and test whether the interaction between hPDI, sociodemographic, and lifestyle variables modifies this association. Methods: This longitudinal study included 3192 (F = 2125, average age 34 years) participants from the Cohort of Universities of Minas Gerais (CUME Study, Brazil, 2016-2022). Dietary intakes were assessed using a validated food frequency questionnaire. We measured three plant-based diet indices: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). Participants were classified as new cases of hypertension if they were free of this disease at baseline, had a systolic blood pressure ≥ 140 mmHg, a diastolic blood pressure ≥90 mmHg, were using antihypertensive medications, or had a diagnosis of hypertension by a physician in at least one of the follow-ups. Crude and adjusted Cox regression models were used to evaluate the relationship between plant-based diet indices and hypertension incidence and a multiplicative interaction was tested. Results: The incidence of hypertension was 19,8/1000 person-years total. The mean follow-up time was 3.36 years. There was an inverse association between the highest quintiles of hPDI (HR = 0.56, 95% CI = 0.37–0.86; HR = 0.55, 95% CI = 0.35–0.88) and hypertension. In subgroup analysis, inverse associations between hPDI and hypertension risk were stronger in participants who were insufficiently active and overweight (p-interaction < 0.05). Conclusion: Greater consumption of healthful plant foods, reduced consumption of animal-source foods, and less consumption of unhealthful plant foods are important for hypertension prevention in the Brazilian population.