The Effect of Continuous Ambulatory Peritoneal Dialysis on Change in Serum Leptin

Abstract

Objective Elevated serum leptin can contribute to anorexia and poor nutrition in patients with chronic renal failure, because leptin is elevated in chronic renal failure patients with or without dialysis, especially in chronic ambulatory peritoneal dialysis (CAPO) patients. The aim of this study was to find whether leptin can be removed by peritoneal dialysis (PO) and to analyze factors that can affect serum leptin after start of CAPO by observing the change in serum leptin shortly after start of CAPO and its correlation with body mass index (BMI), with serum insulin, and with residual renal function. Design Twenty patients who started CAPO during the observation period were studied. Serum leptin was measured by radioimmunoassay before start of CAPO, 3 5 days after start of CAPO, and 1 month and 3 months after start of CAPO. Simultaneously, body weight, serum insulin, and residual renal function were measured. To compensate for the circardian rhythm of leptin, removal of leptin was assessed by measuring dialysate leptin divided by average serum leptin before and after a peritoneal equilibration test (PET). Results Leptin was eliminated by PO with a dialysateto-serum ratio of 0.16 ± 0.07, which was comparable to removal of β2-microglobulin (0.14 ± 0.06). The mean serum leptin concentrations did not decrease after 3 5 days of CAPO (8.4 ± 13.1 ng/mL → 11.9 ± 18.0 ng/mL) despite its removal by PO, and levels increased markedly to 189% of basal serum leptin 1 month after start of PO and to 260% of basal serum leptin 3 months after start of PO. Correlation coefficients (Spearman's p) between change of serum leptin and change of BMI, of serum insulin, of glomerular filtration rate (average of urine creatinine clearance and urine urea clearance) were 0.267 (p > 0.05, n = 20),0.441 (p > 0.05, n = 16),0.706 (p > 0.05, n = 8) respectively. Conclusion Leptin is removed by peritoneal dialysis. Serum leptin did not decrease in 5 days after the start of PO despite its removal by PO, but increased markedly thereafter, within 3 months after start of PO. We could not find a significant correlation between the change in leptin and the change in BMI. Factors other than fat-mass gain can stimulate leptin increase shortly after start of PO.

Adipokines and parameters of peritoneal membrane transport in newly started peritoneal dialysis patients.

“…Nanayakkara et al presented negative linear association between eGFR and plasma leptin in patients with CKD (Nanayakkara et al, 2009). It has been reported that the start of PD treatment is associated with a marked increase in serum leptin levels (Kim et al, 1999;Teta et al, 2008). What is interesting is that leptin can be eliminated by PD.…”

Glucose-containing peritoneal dialysis fluids regulate leptin secretion from 3T3-L1 adipocytes

“…Among patients undergoing renal replacement therapy, those treated by peritoneal dialysis (PD) have extraordinarily raised serum leptin, clearly out of proportion to the fat accumulation observed in these patients [2]. In addition, serum leptin increases by 189% within 1 month after starting PD treatment, in spite of significant leptin removal by the peritoneal route [3]. It is therefore probable that factors other than fat mass stimulate leptin production in PD.…”

Left Ventricular Diastolic Dysfunction in Peritoneal Dialysis

“…Increase in adiposity is reported to be a source of inflammatory cytokines or adipokines, for example, leptin, which is increased in PD patients. 28 Leptin is also reported to have strong interaction with proinflammatory cytokines including interleukin-1 and tissue necrosis factor-α. 29 Finally, there are studies about persistent release of proinflammatory mediators in PD patients with maintenance or after an episode of peritonitis.…”