Nutritional Status in Continuous Ambulatory Peritoneal Dialysis Patients

Abstract

Many studies have documented the poor nutritional status of long-term dialysis patients (14). This has been attributed to a number of factors, including the hormonal and metabolic alterations of uremia (5). Whilst on hemodialysis (HD), patients are also subjected to the catabolic stress of the dialysis process itself (6). It is now known that catabolic factors including protease, interleukin, and tumor necrosis factor are released during HD (7). Metabolic acidosis may also contribute to depletion of nutritional status in this patient group (8). In addition, amino acids are lost during the dialysis process losses have been estimated at 1 -2 g per hour of dialysis (9).

Continuous ambulatory peritoneal dialysis (CAPD) has become increasingly popular as a form of maintenance dialysis for patients with chronic renal failure. Whilst these patients are not exposed to the regular catabolic stress of hemodialysis sessions and tend to be less acidotic than HD patients, they do, however, have the nutritional disadvantage of large losses of protein through the peritoneum, often exacerbated by bouts of peritonitis. It has been estimated that 0.5 2 g protein are lost per liter of dialysate (10).

Other factors contributing to malnutrition in dialysis patients include catabolic illnesses and poor dietary intake. The latter may be a result of psychological or social factors, concurrent illness, or possibly inadequate dialysis. Malnutrition is widely documented to be a contributing factor in the morbidity and mortality of these patients (11–13). We undertook a study to compare the nutritional status of patients treated with both modes of dialysis to each other and to a control group, using anthropometric and biochemical markers of nutrition.