Kt/V, nutritional parameters, serum cortisol, and insulin growth factor-1 levels and patient outcome in hemodialysis

Despite many technical advances in dialysis care, morbidity and mortality in chronic hemodialysis patients in the United States remains high. In this study, we analyzed the effects of Kt/V, nutritional parameters (serum albumin level, triceps skin-fold thickness, mid-arm muscle circumference, and normalized protein catabolic rate), and predialysis serum cortisol and insulin growth factor-1 levels on predicting morbidity and mortality. The cohort studied consisted of 52 patients recruited from a single outpatient dialysis facility. Cox proportional hazards modeling indicated that only Kt/V predicted subsequent mortality (P = 0.02), while both predialysis cortisol levels (P = 0.03) and Kt/V (P = 0.03) predicted hospitalization. Kaplan-Meier analysis demonstrated that the ability of cortisol levels to predict hospitalization was largely confined to the group with values greater than 22 micrograms/dL predialysis. High serum cortisol levels were correlated with low serum albumin levels and a trend toward low triceps skin-fold thickness and higher normalized protein catabolic rate, suggesting a catabolic state. Both predialysis serum cortisol and insulin growth factor-1 levels were higher than those in age- and sex-matched normal human controls. These results demonstrate the importance role of Kt/V in predicting subsequent hospitalization rates and mortality, and that high predialysis serum cortisol levels correlate with a high hospitalization rate.