Hyperleptinemia in uremic patients undergoing conservative management, peritoneal dialysis, and hemodialysis: A comparative analysis

We performed a cross-sectional study in a wide sample of patients with chro nic renal failure undergoing conservative therapy (CTh) (n = 79), peritonea l dialysis (PD) (n = 75), and hemodialysis (HD) (n = 51), with the aim of a nalyzing the impact of the different modes of therapy on serum leptin level s, We used a multivariate approach, taking into consideration the potential effects of other epidemiological, dialysis-related, nutritional, and hormo nal factors on serum leptin. Leptin levels were higher in patients treated with PD (median, 36 ng/mL) than in those undergoing CTh (10.8 ng/mL) or HD( 5.4 ng/mL) (P < 0.0005), This difference persisted after controlling for ge nder, body mass index, and fasting insulin levels, suggesting that imbalanc es in these factors may only partially explain the differences found betwee n the three modes of therapy. Leptin levels showed a significant negative c orrelation with peritoneal protein losses in PD patients but were poorly as sociated with factors such as proteinuria, daily peritoneal glucose absorpt ion (PD), renal function, or adequacy of dialysis, Leptin and insulin-like growth factor-I (IGF-I) were significantly correlated in PD patients, but t he study design did not allow for establishing a meaning for this correlati on, In conclusion, serum leptin levels are increased in PD patients when co mpared with CTh or HD patients. Differences in gender distribution, fat mas s, and insulin levels may partially explain these findings, but other undef ined factors also may have a role in producing these results, (C) 1999 by t he National Kidney Foundation, Inc.