Survival and factors predicting mortality in hemodialysis patients over 75 years old.

BACKGROUND: Patients starting dialysis treatments are increasingly elderly and with high morbidity and mortality. Survival and factors influencing mortality are discussed.

METHODS: We studied 2,601 patients who started hemodialysis in Andalucía (Spain) between 2004 and 2007. Of these, 71 patients died in the first 90 days of hemodialysis treatment and were excluded. Three groups were considered: group A, 694 patients aged less than 60 years; group B, 1,203 patients between 60 and 75 years; and group C, 704 patients aged over 75. Survival and factors associated with mortality were studied.

RESULTS: Mean survival was 46 months in group A, 41.6 in group B and 35 in the very elderly group. In univariate analysis using the Cox proportional hazards model, survival in the very elderly patients was significantly influenced by low body mass index (BMI), venous catheter as initial vascular access, arterial hypertension, congestive heart failure (CHF), late referral to nephrologist (<6 months), C-reactive protein (CRP) >10 mg/dL, serum albumin <3.5 g/dL, Kt/V (Daugirdas) <1.2 and time of dialysis session <180 minutes. In multivariate analysis, BMI, CHF, CRP, low serum albumin, Kt/V and time of dialysis session remained as independent predictors of mortality.

CONCLUSIONS: Survival of the very elderly patients who remained on hemodialysis more than 90 consecutive days was poor (about 3 years). Heart failure and malnutrition/inflammation are prognostic factors related to mortality in these patients on chronic hemodialysis.