Pollock et al.
Total body nitrogen as a prognostic marker in maintenance dialysis patients

J Am Soc Nephrol (Jul) 6:82-88 1995

Pollock et al compare nutritional parameters in 154 dialysis patients [82 PD and 74 HD] in a single centre, predominantly cross-sectional, study of prevalent patients. As well as standard nutritional indices, they measure total body nitrogen [TBN] using prompt neutron activation analysis, a technique they have studied before. They also calculate nitrogen index [NI] which is a ratio of actual:predicted TBN.

They show that, compared to their HD patients, their PD patients have been less time on dialysis, are larger, have greater percentage body fat and lean body mass, have higher NI, have similar protein and caloric intake, but have lower serum albumin. They show NI to be a good predictor of survival with a value less than 80% associated with a more than fourfold increase in one year mortality. In HD, but not in PD, NI correlates with serum albumin and caloric intake but not protein intake. Surprisingly, in two year follow-up studies of 36 HD and 26 PD patients still on the same modality, there was no change in NI on HD but a significant improvement on PD.

Comment: Notable points in this study are high PD usage [>50%] and a low proportion of diabetics [8%]. Problems with the study are the somewhat confusing methodology, the difficulty distinguishing between those differences that preceded modality selection and those that resulted from it, and the usual problems with case mix in any modality comparison study. Compared with the recent Cianciaruso paper [AJKD 1995; 26:475] which emphasized subjective global nutritional assessment, the Pollock study is more favourable to PD. This may reflect the different case mix or perhaps the different techniques used. (Blake)

To go back use the BACK button on your browser.
Otherwise click on the desired link to this article below:
CRF by organ system : Nutrition
CRF: Problem Areas : Outcomes (Morbidity, Mortality)