Trajectories of healthy aging and their association with the Mediterranean diet: The HELIAD Study

Abstract

Background: The aim of the present study was to investigate the association of adherence to the Mediterranean diet with trajectories of healthy aging. Methods: The dataset of the Hellenic Longitudinal Investigation of Aging and Diet was the basis for the present longitudinal analysis. In a sample of 1226 older (> 65 years) adults (704 women), adherence to the Mediterranean diet was assessed through the calculation of the MedDietScore. A healthy aging metric was introduced using an item response theory (IRT) approach based on information from validated questionnaires assessing functionality and cognition. Four trajectories of healthy aging were created based on whether the healthy aging status of participants was above or below the median at baseline and follow-up: High-High, High-Low, Low-High and Low-Low. The association of adherence to the Mediterranean diet with the trajectories was investigated using a multinomial logistic regression with the Low-Low group set as reference, while adjusting for potential confounders. Results: 34.3% of participants belonged to the High-High group, 15.7% to the High-Low, 18.6% to the Low-High and 31.4% to the Low-Low group. Greater adherence to the Mediterranean diet was significantly associated with the probability of having one of the healthier trajectories (i.e., Low-High or High-High). Substitution analysis revealed that substituting energy intake from proteins and lipids with carbohydrates was associated with a lower probability of having one of the favorable trajectories. Conclusion: Greater adherence to the Mediterranean diet was associated with more favorable trajectories of aging and policies to raise awareness about its significance should be implemented. © 2022