Background
Studies reporting renal and overall survival after acute kidney injury (AKI) treated exclusively with intermittent modalities of renal replacement therapy (IRRT) are rare. This study focused on outcomes of AKI patients treated with IRRT both in intensive care units (ICUs) and non‐ICU dialysis units.

Methods
This prospective observational study was carried on during a 5‐month period in 17 ICUs and 17 non‐ICUs. ICU and non‐ICU patients (total n = 138; 65 ICU, 73 non‐ICU) requiring RRT for AKI and chosen to receive IRRT were included. Patient and RRT characteristics as well as outcomes at 90 days, 1 year, and 3 years were registered.

Results
Characteristics of ICU and non‐ICU patients differed markedly. Pre‐existing chronic kidney disease (CKD) and chronic heart failure were significantly more common among non‐ICU patients. At 1 year, RRT dependence was significantly more common in the non‐ICU group. At 3 years, there was no significant difference between the groups either in RRT dependence or mortality.

Conclusion
Outcome of AKI patients treated with IRRT is dismal with regard to 3‐year kidney function and mortality. Although pre‐existing CKD emerged as a major risk factor for end‐stage renal disease after AKI, the poor kidney survival was also seen in patients without prior CKD.