Acute Kidney Injury in a Chinese Hospitalized Population

Objectives: This study's objective was to determine the incidence and mortality rate of acute kidney injury (AKI) among hospitalized adult patients in a tertiary metropolitan hospital of China, and to evaluate the impact of AKI on in-hospital mortality, cost and length of stay (LOS). Methods: Patients who were admitted to Zhongshan Hospital, Fudan University, Shanghai, China between September 1st, 2004 and June 30th, 2008 were involved. The presence and severity of AKI were assessed using absolute and relative increases from baseline to peak serum creatinine concentration during hospitalization. AKI was defined as a relative 50% increase or an absolute increment of 0.3 mg/dl (26.5 mu mol/l) in serum creatinine within 48 h. After screening the computer-based data on kidney function, patients with AKI were identified and further history reviews were performed to obtain information regarding patients' demography, prognosis, severity of kidney injury and causes of AKI. Results: There were 176,155 admissions during the study period and 5,619 met the diagnostic criteria of AKI. The overall incidence rate of AKI was 3.19%. Cardiovascular diseases followed by urogenital diseases and malignancy were the most common admission diagnoses. In-hospital mortality rate was 2.84% in all discharges and 19.68% in patients with AKI. Of AKI patients, old age, intensive care unit admission, Acute Kidney Injury Network score, need for renal replacement therapy and organ system failure number were independent predictors of hospital mortality according to forward conditional logistic regression. Conclusions: AKI is prevalent in the Chinese hospitalized patients. Slight elevations of serum creatinine are associated with significantly increased mortality, LOS and hospital cost. Moreover, outcomes are related directly to the severity of AKI characterized by percent changes in serum creatinine. Copyright (C) 2010 S. Karger AG, Basel