Impact of dietary counseling on Mediterranean diet principles on dietary fiber intake and serum uremic toxins in patients treated with peritoneal dialysis: A pilot study.

INTRODUCTION: The Mediterranean diet (MD) offers numerous health benefits, including improvements in cardiovascular health, cognitive function, and reduced inflammation. Its role in patients with chronic kidney disease (CKD), particularly those undergoing peritoneal dialysis (PD), remains understudied, but attractive. This study evaluated achieved adherence to the MD, impact on dietary fiber intake, and serum uremic toxins in PD patients.

MATERIALS AND METHODS: An interventional randomized pilot study was conducted on 21 PD patients, randomized into intervention (MD diet counseling) and control groups (standard diet). Dietary intake, fiber consumption, serum potassium, phosphate and serum uremic toxins (trimethylamine-N-oxide (TMAO), p-cresyl sulfate (pCS), and indoxyl sulfate (IS)) were measured before and after a 4-week intervention. Dietary adherence was assessed using the Mediterranean Diet Adherence Screener (MEDAS). Statistical analyses compared the changes between groups.

RESULTS: Adherence to the principles of MD significantly improved in the intervention group (MEDAS: 6.6 ± 1.0 to 8.8 ± 1.2, p < 0.001). Dietary fiber intake increased modestly but not significantly (16.7 ± 6.7 g/day to 19.8 ± 7.5 g/day, p = 0.374). Serum levels of uremic toxins showed no significant change, while potassium and phosphate levels remained stable.

CONCLUSION: The MD counseling improved dietary adherence to the goals of MD without negatively affecting serum electrolyte and phosphate control in PD patients. No significant changes were observed in serum uremic toxin levels or dietary fiber intake.