Beneficial short term effect of low protein diet on chronic kidney disease pro-gression in patients with chronic kidney disease stage G3a. A pilot study.

Introduction: The effectiveness of a low protein diet (LPD) to delay the progression of chronic kidney disease (CKD) remains controversial. The questions persist regarding which LPD for which CKD patients? Our study aimed to investigate the role of LPD in selected patients with CKD stage G3a.

Methods: Forty-seven selected patients (23 men, mean age 55 ± 12), in stage G3a of CKD (eGFR: 45-59 ml/min) were included in this prospective 12 months study with a recommended dietary protein intake (DPI) of 0.8 g/kg/day. The DPI was estimated from 24 h urinary urea nitrogen excretion (Maroni formula).  All patients were trained by dietitian-nutritionist and had one baseline control and three visits. The clinical data, blood pressure, diet-adherence, eGFR, albumin, cholesterol, hemoglobin, proteinuria, and BMI were analyzed.

Results: According to the adherence to LPD, the patients were divided into Adherent group (AG, n =24, 51 %) with DPI of 0.75 ± 0.25 g/kg/day and non-Adherent group (NAG, n =23, 49 %) with DPI of 1.3 ± 0.31 g/kg/day. During the follow up the eGFR decreased from 57.68 ± 4.0 to 56.11 ± 4.8, and from 55.45 ± 7.0 to 52.46 ± 7.2 for AG and NAG, respectively. The real drop of eGFR after 12 months was 1.57 for AG and 2.99 ml/min for NAG. The difference was statistically significant (p <0.01).

Conclusion: Despite the significant percentage of non-adherent patients, our pilot study confirms the beneficial effect of LPD on CKD progression. Adherent patients in G3a stage protect more successfully their GFR compared with non-adherent patients after 12 months. CKD stages with mild reduction of GFR are more challenging for further clinical studies. HIPPOKRATIA 2018, 22(4): 178-182.