Mortality Predictors in Elderly Intensive Care Unit Patients with Acute Kidney Injury Requiring Hemodialysis

Abstract

Introduction: The incidence of acute kidney injury is increasing in the elderly. This condition is especially serious during the course of critical illness, and the rate of mortality rises with the condition’s increasing severity. We aimed to identify the risk factors for in-hospital, 28-day, and 90-day mortality among elderly patients admitted to the intensive care unit with acute kidney injury requiring dialysis. Materials and Method: We conducted a retrospective study between January 2011 and December 2019 of patients 65 years of age and older who were hospitalized with acute kidney injury requiring dialysis in the intensive care unit of an internal medicine department. Results: A total of 144 patients were evaluated, 63 male (43.75%) and 81 female (56.25%). The in-hospital, 28-day, and 90-day mortality rates were 40.9%, 47.2%, and 56.2%, respectively. Sepsis etiology was associated with poor prognosis. In univariate Cox regression analysis, we identified use of inotropes, final C-reactive protein, neutrophil to lymphocyte ratio as mortality predictors at all three time points. Use of inotropes, final C-reactive protein continued to be predictors of mortality in multivariate analysis. Age was not found to be a factor affecting mortality. Conclusions: Data are limited on the outcomes of elderly patients with acute kidney injury requiring dialysis, but routinely evaluated laboratory parameters in intensive care practice may be predictive of mortality. Our results provide deeper understanding of how these variables interact and contribute to the risk of mortality. Chronological age alone should not be a consideration for hemodialysis. Keywords: Aged; Critical Care; Hemodialysis; Acute Kidney Injury; Mortality.