Abstract MP36: Association Between The Quality Of Plant-based Diets And Risk Of Frailty

Importance: The Mediterranean diet, and other dietary patterns rich in fruits and vegetables, have been linked to lower risk of frailty in older adults. However, not all plant-based diets are necessarily healthful, and no previous study has evaluated the role of the quality of plant-based dietary patterns in frailty risk. Objective: To assess the association between plant-based diet quality and risk of frailty. Design, setting, and participants: Prospective cohort with 82,234 women aged ≥60y from the Nurses’ Health Study, who were followed from 1990 through 2014. The dates of analysis were April 14 to -June 23, 2021. Exposures: Dietary data were collected every 4-y using a validated semi-quantitative food frequency questionnaire. The plant-based diet quality was assessed with 2 indices (range 18 - 90 points).: a) Healthful Plant-Based Diet Index (hPDI), where healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea/coffee) received positive scores, while less healthy plant foods (fruit juices, sweetened beverages, refined grains, potatoes, sweets/desserts) and animal foods received reverse scores; and b) Unhealthful Plant-Based Diet Index (uPDI) where positive scores were given to less healthy plant foods and reverse scores to healthy plant foods and animal foods. Main outcomes: Frailty incidence was assessed every 4 years, being defined as having ≥3 of the following 5 criteria from the FRAIL scale: fatigue, low strength, reduced aerobic capacity, having ≥5 illnesses, and weight loss ≥5%. Methods: Multivariable-adjusted Cox proportional-hazards models were used to estimate hazard ratios (HRs), and their 95% confidence interval (CI). Results: We identified 12,910 incident cases of frailty over 1,176,401 person-year follow-up. In the multivariable analysis, the hPDI was inversely associated with the risk of frailty (HR for the highest vs. lowest quintile: 0.69, 95% CI: 0.65-0.73; p-trend<0.001). In addition, a 10-unit increment in the hPDI was associated with a relative 20% lower risk of frailty. Conversely, a direct association was found between the uPDI and risk of frailty (HR highest vs. lowest quintile: 1.41, 95% CI: 1.32-1.49]; p-trend<0.001). These associations were consistent for each frailty criterion, among participants with no frailty criteria at baseline, after excluding participants with diabetes, cancer, and CVD at baseline, for alternative versions of the PDIs, in subgroup analysis by categories of potential confounders, and in latency analysis. Conclusions and relevance: A healthful plant-based diet was associated with lower risk of frailty whereas an unhealthful plant-based diet was associated with higher risk.