Are serum albumin and cholesterol reliable outcome markers in elderly dialysis patients?

ABSTRACT

Albumin and cholesterol are considered reliable outcome markers in dialysis patients; their influence, however, may also be related to non-independent factors, such as age and presence of co-morbid conditions. The aim of the study was an analysis of four outcome markers, assessed at start of dialysis age, high risk conditions, cholesterol and albumin levels. Data were obtained from the Piedmont Dialysis and Transplantation Registry (northern Italy, about 4,400,000 inhabitants, 21 dialysis centres, open acceptance since mid-1970s, 5661 patients on file at 31 December 1992). Prevalence of albumin and cholesterol in the normal range increases with age; in each age group prevalence in the range is higher in patients at high risk. However, influence of these biochemical parameters is evident also in no-risk cohorts, thus identifying a subgroup with poorer prognosis also in the population without any identified classic risk factor. The influence of albumin, more evident in the population studied compared with cholesterol, is reflected by impaired survival of low-albumin patients (age > or = 65 high risk at 1 year 60.7% vs 76.6%, P = 0.0052; age > or = 65 non-high risk, at 1 year 76.5% vs 90.7%, P = 0.0001). In conclusion, albumin and cholesterol, assessed at start of dialysis, are reliable outcome markers even in elderly patients, identifying, in this high mortality cohort, a subgroup with poorer prognosis. If and how their effect may be reversed by dialysis therapy remains to be assessed.