# Time for Change: A 3-Year Prospective Study on Mediterranean Diet Adherence and Body Composition in Kidney Transplant Recipients

## TL;DR

This study found that kidney transplant recipients' adherence to the Mediterranean diet and muscle mass declined over three years, with dietary and clinical factors linked to mortality.

## Contribution

The study provides new insights into the long-term dietary adherence and body composition changes in kidney transplant recipients and their clinical associations.

## Key findings

- Mediterranean diet adherence significantly decreased over three years, particularly in vegetable, fruit, and fish intake.
- Skeletal muscle mass declined significantly, while fat mass and kidney function remained stable.
- Cereal intake, blood glucose, cholesterol, and diabetes were predictive of muscle mass loss.

## Abstract

Background: The aim of this prospective follow-up study was to evaluate changes in body composition parameters and Mediterranean diet (MeDi) adherence among kidney transplant recipients (KTRs) over a three-year period. Additionally, this study sought to investigate the associations between these changes and clinical parameters, including laboratory parameters, new onset of diseases, and death outcome. Methods: A total of 116 KTRs were initially assessed in 2019 and subsequently re-evaluated in 2022. The Mediterranean Diet Serving Score (MDSS) was used to assess dietary adherence to the MeDi at baseline and follow-up assessments. Bioelectrical impedance analysis was used to assess body composition and clinical outcomes were assessed by the data available from medical charts. Results: After three years, MeDi adherence significantly decreased (p = 0.028) from 15 (18.29%) to 5 (6%), with dominantly lower adherence for vegetable, fruit, legume, red meat, olive oil and fish intake. Regarding body composition parameters, the most prominent change was seen in muscle mass, which deteriorated from 41.77% (IQR 6.46) to 39% (IQR 6.14; p = 0.004). However, changes in fat mass level were not significant in the follow-up period. Furthermore, cereal intake, fasting blood glucose (FBG), cholesterol level, level of low-density lipoprotein cholesterol (LDL), triglyceride leve and presence of diabetes mellitus lwere shown to be predictive for the decline of skeletal muscle mass. There were no significant changes in the estimated glomerular filtration rate (eGFR) or albuminuria level during the follow-up period. Associations with the death outcome were found for the MeDi-advised intake of eggs (β = −1.06, HR = 0.35, CI (0.14–0.87), p = 0.023), phase angle (PhA) (β = −2.68, HR = 0.07, CI (0.01–0.43), p = 0.004), cholesterol level (β = 0.95, HR = 2.60, CI (1.40–4.70), p = 0.001) and calcium level (β = −7.21, HR = 0.00, CI (0.00–1.50), p = 0.063). Conclusions: This study highlights a significant decline in MeDi adherence and skeletal muscle mass among KTRs over a three-year follow-up period, with no notable changes in fat mass or kidney function. The predictors of muscle mass loss and associations with mortality underscore the importance of dietary and clinical management in this population.