THE HEMODIALYSIS PRESCRIPTION AND QUALITY-ADJUSTED LIFE EXPECTANCY

What comprises an optimal prescription for uremic-toxin clearance in t he chronic hemodialysis setting is a much disputed issue. The dispute is underscored by the rise in mortality of the U.S. dialysis populatio n during the 1980s and reports of significant noncompliance with minim al treatment standards recommended from the National Cooperative Dialy sis Study. A decision model was developed to summarize and test assump tions about the effect of various dialytic-treatment options on patien t outcomes. Treatment options included delivered fractional urea clear ance (Kt/V), dialysis-treatment duration, dialysis membrane (high flux versus conventional), dialysate (bicarbonate versus acetate), and ult rafiltration (controlled versus uncontrolled). The expected outcome fo r any set of treatment options was calculated as a function of a repre sentative patient's life expectancy, adjusted for the probability and assumed importance of avoiding uremia- and treatment-related complicat ions, referred to as quality-adjusted life expectancy (QALE). QALE inc reased by 59 days for each 0.1-U increase in Kt/V and by 187 days with high-flux dialysis. Controlled ultrafiltration with bicarbonate dialy sis increased QALE by 30 days compared with uncontrolled ultrafiltrati on with acetate dialysis. Sensitivity analyses showed that, under cons ervative assumptions, QALE increased 11 days for every 0.1 increment i n Kt/V. The model afforded a framework for reviewing the literature an d testing assumptions about the expected benefits of dialytic-treatmen t options for the development of a clinical guideline on the adequacy of dialysis.