[Relation between serum leptin levels and selected nutritional parameters in hemodialyzed patients]

Leptin is a protein hormone produced predominantly by adipocytes. Its serum concentrations positively correlate with body fat content and body mass index (BMI) i.e. they are lower in lean than obese subjects. The aim of our study was to compare serum levels of leptin, selected nutritional parameters and serum lipids in hemodialysed patients (n = 46) and healthy subjects (n = 24) and to explore the relationship between serum leptin levels and the rest of nutritional parameters in both groups. The tendency towards higher serum leptin levels in hemodialysed patients compared to control group was found, but the difference did not reach the statistical significance (24.31 +/- 24.06 ng/ml vs. 7.97 +/- 4.4 ng/ml). The leptin/body fat content ratio was significantly higher in hemodialysed patients compared to control subjects (0.85 +/- 0.74 vs. 0.27 +/- 0.11, p plain 0.01). The serum total protein, transpherine, albumin and cholesterol levels were significantly lower in hemodialysed patients compared to control group (68.14 +/- 5.56 g/l vs. 75.53 +/- 3.43 g/l; 2.04 +/- 0.49 g/l vs. 2.5 +/- 0.23 g/l; 33.65 +/- 2.86 g/l vs. 48.38 +/- 3.5 g/l; 4.56 +/- 1.19 mmol/l vs. 5.82 +/- 0.98 mmol/l; p = 0.001). Serum triglyceride levels were significantly lower in hemodialysed patients compared to controls (1.29 +/- 0.5 mmol/l vs. 2.31 +/- 1.23 mmol/l, p < 0.0001). Serum leptin levels in hemodialysed patients correlated positively with body fat content, serum cholesterol and triglyceride levels. In the control group only the significant positive correlation with body fat content was found. In conclusion, this study demonstrated relatively higher serum leptin levels in hemodialysed patients compared to healthy subjects, although their nutritional status expressed by serum protein nutritional parameters and body fat content is significantly impaired. Except of the positive correlation with serum lipids levels no statistically significant relationships between serum leptin levels and biochemical nutritional parameters were found in our study.