The relationship between plasma leptin and nutritional status in chronic hemodialysis patients

Leptin serves an important role in suppressing appetite in mice and is know n to be elevated in chronic renal failure (CRF) patients. But clinical sign ificance of leptin as an appetite-reducing uremic toxin, remains to be dete rmined. So we studied the relationship between plasma leptin and nutritiona l status in 46 chronic hemodialysis (HD) patients. Pre HD leptin was measur ed and divided by body mass index (BMI) to give adjusted leptin levels. KT/ V-urea (K, dialyzer urea clearance; T, duration of HD; V, volume of distrib ution of urea), C-reactive protein (CRP), plasma insulin and nutritional pa rameters such as serum albumin, normalized protein catabolic rate (nPCR), s ubjective global assessment (SGA), BMI and mid-arm muscle circumference (MA MC) were also measured. Mean plasma leptin levels were 8.13+/-2.91 ng/mL(ma le 3.15+/-0.70; female 14.07+/- 6.14, p<0.05). Adjusted leptin levels were positively correlated with nPCR (male r=0.47, p<0.05; female r=0.46, p<0.05 ), SGA (male r=0.43, p<0.05; female r=0.51, p<0.05) and MAMC (male r=0.60, p<0.005; female r=0.61, p<0.05). They did not correlate with KT/V-urea, ser um albumin, hematocrit, bicarbonate, insulin and CRP. Presence of DM and er ythropoietin therapy had no effect on leptin levels. These results suggest that leptin is a marker of good nutritional status rather than a cause of p rotein energy malnutrition in chronic HD patients.