Long-Term Mortality among Hospitalized Non-ICU Patients with Acute Kidney Injury Referred to Nephrology

Nephron. 2015;131(1):23-33. doi: 10.1159/000437340. Epub 2015 Aug 12.

Abstract

Background: Epidemiological studies of acute kidney injury (AKI) have focused on patients admitted to intensive care units (ICUs), and several have studied hospitalized non-ICU patients, but analysis of patients referred to Nephrology is sparse. We analyzed factors associated with short- and long-term morbimortality among hospitalized non-ICU patients with AKI who were referred to Nephrology.

Methods: A retrospective study with data prospectively collected from 170 non-ICU patients, with referral to the Nephrology Unit, recruited over a 4-year period, was performed. AKI was classified according to the criteria based on risk, injury, failure, loss of kidney function and end-stage kidney disease (RIFLE). Risk factors that could influence prognosis of AKI and long-term mortality were analyzed at admission. Early on, 1- and 10-year mortalities were correlated with AKI RIFLE class, clinical and demographic characteristics.

Results: Most patients were >65 years, with multiple comorbidities and frequent drug intake history. Median Charlson score was 6. Twenty-five percent of patients with previously unknown chronic kidney disease (CKD) were diagnosed with CKD during the study. Dialysis was required in 13.5% of patients. Hospital deaths were 22.4% and significantly associated with older age, RIFLE class L, higher peak serum creatinine, oliguria and decreased serum albumin levels. One-year (38.8%) and 10-year (68.8%) mortalities were significantly associated with age, prior cardiovascular disease, prior CKD and RIFLE class L. According to the Cox proportional hazard model, age, prior CKD and RIFLE class L were independent risk factors of death at 1 and 10 years.

Conclusions: AKI in hospitalized non-ICU patients is associated with high early and late mortality. This study increases our understanding of AKI among this specific population and can improve their management.

MeSH terms

  • Acute Kidney Injury / mortality*
  • Aged
  • Comorbidity
  • Creatinine / blood
  • Female
  • Hospital Mortality
  • Humans
  • Kidney Failure, Chronic / mortality
  • Kidney Failure, Chronic / physiopathology
  • Kidney Function Tests
  • Male
  • Nephrology
  • Prospective Studies
  • Renal Insufficiency / mortality
  • Renal Insufficiency / physiopathology
  • Renal Insufficiency, Chronic / mortality
  • Renal Insufficiency, Chronic / physiopathology
  • Retrospective Studies
  • Risk Factors
  • Serum Albumin / metabolism
  • Survival Analysis

Substances

  • Serum Albumin
  • Creatinine