Hospital-acquired acute kidney injury: an analysis of baseline estimated glomerular filtration rate and in-hospital mortality

Aim The objective of this study was to determine whether the baseline estimated glomerular filtration rate (eGFR) level was independently associated with in-hospital mortality in generalized patients with hospital-acquired acute kidney injury (HA-AKI) in China. Methods All of the patients admitted to a tertiary medical center of Nanjing, China, between January 1, 2013, and December 31, 2013, were involved. Through the use of an electronic database and the Acute Kidney Injury Network (AKIN) classification, the patients with HA-AKI were indentified. We included the hospitalized adult patients with HA-AKI. Epidemiological information and in-hospital outcomes were collected and were analyzed according to different baseline eGFR strata of the included individual patients. Results Of the 42,664 admissions during the study period, 1327 patients were identified as AKI. The incidence of HA-AKI was 3.1 %. HA-AKI patients with a compromised baseline eGFR tended to be older and had a higher prevalence of various comorbid conditions. With the gradual deterioration of the baseline eGFR, the odds ratio of in-hospital mortality increased incrementally and a graded independent association between the baseline eGFR and in-hospital mortality was observed when the baseline eGFR dropped below 60 ml/min per 1.73 m(2). Conclusion Baseline eGFR was a potential risk factor for in-hospital mortality in HA-AKI. Serum Creatinine (SCr)-based definition of AKI needs to incorporate baseline eGFR to optimize or refine risk stratification.