Serum leptin levels and malnutrition in patients with chronic renal failure.

OBJECTIVE: To investigate the correlation between serum leptin levels, body mass index, and triceps skin fold thickness, which are anthropometric measurements, as well as serum albumin levels in patients with chronic renal failure on hemodialysis. METHODS: We studied 75 patients (48 males, 27 females; ages between 18-82) at the Hemodialysis Unit, Cumhuriyet University Medical School; Private Sivas Dialysis Center; Hemodialysis Unit, Sultan Izzettin Keykavus Hospital; and the Hemodialysis Unit, SSK Sivas Hospital between January 2003 and February 2004. Patients were excluded if they had been on dialysis for less than one year, if they were anuric, or if they had been on dialysis with jugular or subclavian catheter and long-term permanent port catheter. Similarly, patients with diabetes mellitus, chronic pulmonary disorders, and hepatic cirrhosis or hepatitis B, hepatitis C carriers as well as those on active tuberculosis therapy were excluded. C-reactive protein was measured in all patients and those with above normal values were excluded. RESULTS: While the mean age for the males was 44.52 +/- 16.53 years (18-77), it was 48.29 +/- 14.32 years (22-82) for the females. The mean triceps skin fold thickness for males was 6 +/- 1.81 mm (3-11.3 mm), and for females, it was 14.07 +/- 8.79 mm (4.3-33.3 mm). The mean body mass index for males was 20.77 +/- 2.61 kg/m2 (14.8-26.6 kg/m2), and for females, it was 25.36 +/- 6.47 kg/m2 (17.3-42.2 kg/m2). The mean serum leptin level for males was 4.61 +/- 4.20 ngr/dl (0.1-18.7 ngr/dl), and for females, it was 52.06 +/- 61.67 ngr/dl (0.6-172.5 ngr/dl). A positive correlation was observed between triceps skin fold thickness and leptin, both in the male group (r=0.478; p<0.05), and in the female group (r=0.876; p<0.05). Body mass index and leptin were also correlated positively both in the male group (r=0.502; p<0.05) and in the female group (r=0.905; p<0.05). No correlation was established between serum albumin levels and leptin. Leptin did not correlate with other measured parameters CONCLUSION: Our study demonstrates that serum leptin levels positively correlated with body mass index and triceps skin fold thickness, which are malnutrition parameters. Therefore, the leptin hormone may be utilized in obtaining preliminary information regarding malnutrition.

Relationship between serum leptin levels and body composition and markers of malnutrition in nondiabetic patients on peritoneal dialysis or hemodialysis.

BACKGROUND: Leptin is a protein hormone secreted by adipocytes, regulating body fat and food intake. It has been reported that serum leptin levels are high in patients with chronic renal failure, and this fact has been associated with malnutrition and body composition changes in patients on hemodialysis. This present study investigated the relationship between plasma leptin concentrations and body composition and markers of malnutrition in nondiabetic patients diagnosed with end-stage chronic renal failure, treated with continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (HD). METHODS: A total of 152 HD and 32 CAPD patients were enrolled into the study. The body compositions of the patients were established by utilizing a Body Composition Analyzer. Triceps skinfold thickness (TSFT) was measured by using a Harpenden Skinfold Caliper. Serum leptin level was detected by radioimmunoassay in ng/mL through employing a DPC Gambyt-CR gamma counter. Standard laboratory methods were used for measuring the remaining parameters (total protein, albumin, blood urea nitrogen, creatinine, hemoglobin, hematocrit, high-sensitivity C-reactive protein [hsCRP]). RESULTS: No significant difference was observed between the HD and CAPD groups regarding leptin levels. Leptin levels of female patients in both groups were markedly higher when compared with those of men (p = 0.001). Plasma leptin levels in total, as well as for both male and female HD and CAPD patients, significantly correlated positively with age, percent fat, fat mass, body mass index and TSFT (p = 0.001). Serum leptin levels were not found to be correlated with length of time on dialysis, lean body mass, total body water, hsCRP, total protein and albumin levels (p > 0.05). CONCLUSION: The data obtained in this study indicated that serum leptin levels could be instrumental markers in establishing body fat ratio, as well as in determining metabolic and nutritional factors in patients with chronic renal failure.

Heart rate turbulence and heart rate variability in patients with mitral valve prolapse.

AIMS: Heart rate turbulence (HRT) and heart rate variability (HRV) have been shown to be independent and powerful predictors of mortality in a specific group of cardiac patients. However, the predictive values of HRV alone is modest and information on HRV in patients with mitral valve prolapse (MVP) has so far been conflicting. In addition, no studies have previously evaluated HRT in patients with MVP. To define better the effects of MVP on cardiac autonomic function, we assessed HRT and time-domain parameters of HRV in patients with MVP. METHODS AND RESULTS: Fifty patients with MVP and 70 controls without MVP were investigated. The diagnosis of MVP was confirmed by cross-sectional echocardiography in the parasternal long-axis view and apical 4-chamber view. The HRV and turbulence analysis were assessed from a 24-hour Holter recording. When HRT parameters were compared, the values of the HRT onset and slope were significantly lower in MVP patients than in the controls group (-0.109+/-0.207 vs. -0.289+/-0.170%, P=0.001 and 8.6+/-7.2 vs. 11.5+/-7.4 ms/RRI, P=0.043, respectively) and the number of patients who had abnormal HRT onset was significantly higher in the MVP group than in controls (15 vs. 8, P=0.011). In addition, HRV parameters were not statistically different between the two groups. CONCLUSION: Although we found that the decrease in HRV parameters was not significantly different between MVP patients and controls, HRT variables (especially HRT onset) were significantly lower in MVP patients. Therefore, in our opinion, HRT is an attractive, easily applicable, and better way of non-invasive risk prediction compared with another non-invasive risk predictor, HRV.