Visceral protein status and caloric intake in exercising versus nonexercising individuals with end-stage renal disease.
OBJECTIVE
To determine if differences exist in kilocalorie and protein intake and visceral protein levels for patients with End-Stage Renal Disease (ESRD) exercising during dialysis versus not exercising.


DESIGN
Prospective study of 11 patients with ESRD over a study period of 12 weeks.


SETTING
Outpatient renal dialysis clinic.


PATIENTS
Patients with ESRD undergoing hemodialysis (HD) three times weekly who met the following criteria were selected: aged 25 to 65 years, nondiabetic, no current physical activity, blood pressure of 160/95 mm Hg or less at the second hour of HD, no unstable angina pectoris. Eleven patients who met the criteria were randomized into two groups; five patients with exercise (E) and six patients without exercise (NE).


INTERVENTIONS
From weeks 5 to 8, E patients began exercise during HD three times a week. Exercise gradually increased by 3 minutes each dialysis day, maintaining 60% to 80% maximal heart rate (HR). By the end of week 8, all E patients reached 45 minutes of exercise, including 5 minutes each of warm-up and cooldown. Patients continued 45 minutes of exercise each dialysis day during HD at 60% to 80% maximal HR during weeks 9 through 12. NE patients remained sedentary throughout the study.


MAIN OUTCOME MEASURE
Twenty-four-hour dietary recalls were obtained weekly for the 12 weeks from all patients for kilocalorie and protein intake. Serum levels of prealbumin, transferrin, and predialysis and postdialysis albumin were obtained immediately before the study onset and at weeks 4, 8, and 12. Comments related to patients' feelings and exercise were recorded but not analyzed statistically.


RESULTS
Analysis of covariance for repeated measures for kilocalories yielded no significance by group or over time. Mean intakes for E patients for weeks 9 through 12 were clinically greater than weeks 1 through 8 by approximately 200 kilocalories. The mean protein intake for E patients at weeks 9 through 12 (79 +/- 41 g) appeared clinically greater than NE patients at weeks 9 through 12 (58 +/- 11 g), although not statistically different. Adequacy of dialysis (Kt/V) and initial levels of each serum protein were covariates for analysis of variance. No statistical differences were found for prealbumin levels. Transferrin levels were within normal ranges but differed (P <.05) by group (E or NE) and time periods. Prealbumin and postalbumin concentrations ranged from slightly low to adequate levels and were different over time (P <. 05).


CONCLUSION
Kilocalorie and protein intakes appeared to increase for E patients during the exercise program. No consistent increases of visceral proteins were found for E patients. A majority of E patients expressed feelings of improved health, better exercise tolerance, and improved appetite and viewed exercise as enjoyable.