Risk factors for community-acquired acute kidney injury in patients with and without chronic kidney injury and impact of its initial management on prognosis: a prospective observational study

Background: We aimed to describe clinical characteristics of patients with community-acquired acute kidney injury (CA-AKI), the effectiveness of initial management of CA-AKI, its prognosis and the impact of medication on its occurrence in patients with previous chronic kidney injury (CKI). Methods: We undertook a prospective observational study within the Emergency Department (ED) of a University Hospital, screening for any patient >16 years admitted with an eGFR <60 ml/mn/1.73 m(2) and a rise in serum creatinine as compared to previous values. Patients' medical files were reviewed by a panel of nephrologists in the subsequent days and at one and three-years follow-up. Results: From May 1st to June 21st 2013, there were 8464 admissions in the ED, of which 653 had an eGFR <60 ml/mn/1.73 m(2). Of these, 352 had previous CKI, 341 had CA-AKI, and 104 had CA-ACKI (community-acquired acute on chronic kidney injury). Occurrence of superimposed CA-AKI in CKI patients was associated with male gender and with use of diuretics, but not with use of ARBs or ACEIs. Adequate management of CA-AKI defined as identification, diagnostic procedures and therapeutic intervention within 24 h, was recorded in 45% of the cases and was not associated with improved outcomes. Three-year mortality was 21 and 48% in CKI and CA-ACKI patients respectively, and 40% in patients with only CA-AKI (p < 0.001). Mortality was significantly associated with age, hypertension, ischemic heart disease and CA-AKI. Progression of renal insufficiency was associated with male gender and age. Conclusions: CA-AKI is more frequently encountered in male patients and those treated with diuretics and is an independent risk factor for long-term mortality. Its initial adequate management failed to improve outcomes.