Acute Kidney Injury Overlying Chronic Kidney Disease: Clinical Features and Predictors for Renal Recovery of Patients and Inpatient Outcome

Abstract

Background: The combination of acute kidney injury (AKI) with chronic kidney disease (CKD) has been found to have negative implications for renal as well as overall prognosis. However, there is little evidence available on renal recovery and factors influencing it in patients of AKI-on-CKD admitted in Indian hospitals. Aims: The aims of this study were to describe the clinical profile of patients with AKI-on-CKD, determine the factors associated with renal recovery, and their in-hospital outcomes. Materials and Methods: A retrospective cohort study was done on adult patients having existing CKD complicated by AKI, admitted to the hospital during the year 2025. Data on demographic, clinical, biochemical, and treatment variables were collected through the electronic medical record system. Renal recovery at discharge served as the primary outcome measure. Results: A total of 312 patients were recruited, of whom slightly more than half achieved renal recovery. Mortality in-hospital was 17.3% and 41.0% of patients needed renal replacement therapy (RRT). Diabetic nephropathy was the commonest etiology of the underlying CKD, while sepsis was the commonest trigger of AKI. Baseline better renal function was associated with higher chances of renal recovery. However, the presence of severe AKI, sepsis-related AKI, RRT, hypoalbuminemia, and high comorbidities burden were independent predictors of renal non-recovery. Conclusion: AKI-on-CKD was associated with significant mortality and incomplete renal recovery. The following variables have been identified as independent predictors of recovery from renal failure: Baseline renal function, AKI severity, sepsis, nutrition, burden of comorbidity, and RRT. Identifying such characteristics might assist in early identification of patients with high-risk renal complications.