Outcomes Following Acute Kidney Injury Requiring Dialysis: A Cohort Study.

Objective: Retrospective study to examine the outcomes of acute kidney injury requiring dialysis (AKI-D) patients that received outpatient hemodialysis as part of continued AKI-D care and explore factors associated with recovery of kidney function and discontinuation of dialysis.

Methods: Records of all admissions to Emory Dialysis centers between January 2010 to December 2021 were reviewed to include patients with confirmed diagnosis of AKI-D. Basic demographics, comorbidities, duration of hospitalization and cause of AKI were extracted from hospital records and cross-referenced with the dialysis center electronic health record. Patients were followed starting from the day of the first outpatient hemodialysis up to 180 days. All hemodialysis sessions and laboratory data were analyzed. Logistic regression models were used to examine factors associated with recovery of kidney function, defined as survival free of dialysis.

Results: 132 patients were analyzed, corresponding to 12,662 patient-day of outpatient AKI-D care. Among those, 19 (14%) patients died during the observation period. 54% of patients were male and 70% were Black. Median Age was 64 years (IQR 49-79). 42 patients (32%) recovered enough kidney function to discontinue dialysis. Median time to kidney recovery was 31 days (IQR: 19-75), and the cumulative probability of kidney recovery at 6 months was 39%. Patients who discontinued dialysis were younger (58 vs 66 years), had higher estimated glomerular filtration rate (eGFR) at time of admission (69 vs 46 ml/min/1.73m²) to the hospital, and were less likely to have a history of hypertension (61% vs 82%). Intra-dialytic hypotension was more common in patients who did not recover kidney function.

Conclusions: 39% of patients with AKI-D recovered kidney function within 180 days of outpatient HD start. The median time to recovery was 31 days. Younger age, higher e-GFR at time of hospital admission, and absence of hypertension were predictors of kidney recovery. Patients who recover kidney function experienced episodes of intradialytic hypotension less frequently.