Impact on the Proteolysis of Obesity in Dialysis

In hemodialysis patients, the risk of death decreases almost linearly as BMI increases, including in obese patients. Experimental data suggest that obesity may be associated with a reduction of muscle proteolysis during fasting. In the hemodialysis patients, after an overnight fast an increased use of endogenous energy stores has been reported. The objective of the study is to evaluate the potentially "protective" effect of obesity on protein catabolism during short fasting periods. Twenty non diabetic patients (men and women) on maintenance hemodialysis for more than six months, aged of 30 to 70 years, will be included: 10 obese (BMI ≥ 30) and 10 non obese patients (18.5 \<BMI \<25) will be compared with 20 healthy volunteers (men and women) aged 30 to 70 years, obese and non obese, according to the same criteria. On the investigation day, tracer kinetic studies will be associated with resting energy expenditure measurements and body composition analysis (using dual energy x-ray absorptiometry (DXA).