Patients on peritoneal dialysis have a rise in total body weight; hemodialysis patients lose weight.
SAN DIEGO—Body composition tends to change significantly during the first year of dialysis, but the changes depend on which type of dialysis is administered, researchers reported here during Renal Week 2006.
Peritoneal dialysis (PD) patients experience a rise in total body weight compared with hemodialysis (HD) patients, who lose weight. Glucose absorption from the dialysate in PD may be contributing to changes in total body weight, lean body mass, truncal fat, and percentage of body fat, explains Carla Avesani, PhD, a nutritionist at the Federal University of São Paulo in Brazil, who was the lead investigator in a study of 164 patients in Sweden.
Aid to clinical decision-making
“If you are a nephrologist you may want to know which modality is best for patients who need to gain weight or lose weight,” Dr. Avesani said. “This study might help with the decision by the nephrologist when deciding which dialysis modality he will put the patient on.”
Dr. Avesani and collaborators at the Karolinska Institutet in Stockholm, Sweden, prospectively studied 90 PD patients and 74 HD patients. They compared several changes in body composition between the groups before dialysis and after 12 months of dialysis. Body composition was determined by dual energy X-ray absorptiometry. The mean age of the patients was 52 years and 64% were men. Body weight for PD patients at baseline was 69.8 kg, which increased to 71.2 kg a year after starting dialysis. In the HD patients, the mean body weight was 76.7 kg at baseline and 75.1 at 12 months. The two groups had no significant change in BMI.
The total percentage of body fat rose from a mean 29.8% at baseline to 32.9% at 12 months for the PD group. For those on HD, the mean percentage of body fat was 29.1% at baseline and 30.5% at 12 months.
In terms of truncal fat, the mean percentage rose from 30.4% at baseline to 33.7% at 12 months in the PD patients and from 30% to 31.7% in the HD group. Lean body mass decreased from 70.2% at baseline to 67.1% in the PD group and from 70.9% to 69.5% in the HD group.
“Nutritional status is very important,” Dr. Avesani said. “You will see an improvement in terms of survival and quality of life if you can improve nutritional status. We now hope to do follow-up studies to better understand what is happening with these patients in terms of glucose load and other factors that may be contributing to changes in body composition.”