Inflammation and malnutrition as predictors of mortality in patients on hemodialysis.

BACKGROUND

Low albumin and high C-reactive protein (CRP) are significant predictors of mortality in hemodialysis (HD) patients. Although, classically, hypoalbuminemia has been attributed to malnutrition, inflammation can also predict the serum albumin concentration in dialysis patients.

OBJECTIVE

To establish the influence of nutritional status and inflammation on mortality in HD patients.

METHODS

A cross-sectional study was conducted in 64 patients (35 males; 9 diabetics; mean age 64 +/- 12 years), who had been on HD for 64 +/- 58 months. Nutritional status was assessed from estimated protein caloric intake, dietary recall, anthropometric and biochemical parameters, and serum levels of insulin-like growth factor-1 (IGF-1). CRP was used as a marker of inflammation. Comorbidity was measured using a modified M. Charlson index. The dialysis doses (Kt/V) and protein catabolic rate (PCR) were measured and standardized for actual and ideal body weight. The incidence and causes of death were recorded during the two-year follow-up.

RESULTS

During the follow-up period, 18 patients died and 11 were withdrawn from the study after receiving a renal transplant. In multivariante analysis (Cox proportional hazards model), total comorbidity and the levels of CRP and hematocrit (increased) and IGF-1 (decreased) were independent predictors of mortality.

CONCLUSIONS

Inflammation, as measured by CRP, and malnutrition, as measured by IGF-1 levels, are associated with mid-term mortality in HD patients. High hematocrit was an independent risk factor for mortality. Comorbidity, measured by disease and the degree of functional impairment, was a good predictor of mortality.