Outcomes of very elderly treated with dialysis for acute kidney injury


The factors that determine prognosis in elderly patients with dialysis-requiring acute kidney injury (AKI-D) is uncertain. The purpose of this study was to examine predictors of in-hospital mortality in these patients.

A retrospective, single-center study of hospitalized patients ≥ 70 years old with AKI-D. Clinical and demographic variables were compared between survivors and non-survivors, independent predictors of hospital mortality were identified by logistic regression.

Among 137 eligible patients, hospital mortality was 66%; 59% of survivors were dialysis dependent at hospital discharge and 43% of initial survivors died within 1 year post discharge. There was no significant difference in age between survivors (80.2) and non-survivors (80.5) (p = 0.829). Non-survivors had higher rates of altered mental status (68.2 vs. 22.2%, p < 0.001), hypotension (29.5 vs. 13.6%, p = 0.048), leucopenia/leukocytosis (62.6 vs. 42.2%, p = 0.024), ICU admission (59.3 vs. 34.8%, p = 0.007), mechanical ventilation (64 vs. 21.7% p < 0.001), hepatic dysfunction (46.2 vs. 21.7%, p = 0.005), a diagnosis of sepsis (64.8 vs. 26.3%, p = 0.04), and treatment with vasopressors (69.8 vs. 35.6%, p < 0.001). The presence of ≥ 5 of these conditions was associated with > 90% mortality. Logistic regression showed altered mental status (OR = 7.4, 95% CI = 3.0 - 18.2) and mechanical ventilation (OR = 6.0; 95% CI = 2.5 - 14.6, p < 0.001) to independently predict hospital mortality.

Elderly patients with AKI-D have a very high rate of hospital mortality or dialysis-dependent survival. Acute illness severity predicts poor outcome despite dialysis. The decision to dialyze patients in this setting should not be based on age alone but consider prognosis and expected quality of life.
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