Oral protein-energy supplements in peritoneal dialysis: a multicenter study

Protein-energy malnutrition is prevalent in peritoneal dialysis (PD) patients and is associated with increased morbidity and mortality.

To evaluate the impact of prophylactic treatment with an oral protein-energy supplement (Protenplus; Fresenius AG, Bad Homburg, Germany) on nutritional parameters in patients starting PD.

Prospective, multicenter, randomized study of group A patients (Protenplus, n = 35) and group B (controls, n = 30), with evaluations at baseline and at 6 and 12 months.

Efficacy of factors by linear mixed model analysis for repeated measurements, chi-square, t-test, and Mann-Whitney test.

Patient compliance, serum albumin, and other nutritional parameters.

No significant differences were found at baseline evaluation. During follow-up, a significant number of group A patients abandoned intake of the supplement due to non-compliance (n = 7) or side effects (n = 8) (chi2 p < 0.01). Patients with lower residual renal function were less likely to comply. The mixed model in the "intention to treat" analysis showed a significant increase related to supplement intake only in total lymphocyte count in group A. The "as treated" analysis of the 29 patients who fulfilled the study (9 in group A, 20 in group B) disclosed that belonging to group A constituted an independent factor for increased lymphocyte count (p < 0.001), body weight (p < 0.03), tricipital skinfold thickness (p < 0.01), middle-arm muscle circumference (p < 0.025), lean body mass (LBM) (p < 0.002), creatinine LBM related to body surface area (p < 0.001), and creatinine generation rate (p < 0.002). However, these data may have been biased by the high rate of noncompliance in group A.

Protenplus proved to be unsuitable as a long term, oral protein-energy supplement in PD patients due to a high rate of noncompliance and intolerance, primarily among patients with lower residual renal function. The question of whether other products, better-tolerated as nutritional supplements, could compensate for daily protein peritoneal losses in long-term PD remains open.