We aimed to examine different acute kidney injury (AKI) recovery patterns in elderly patients and assess their association with long-term outcomes after AKI. This retrospective study included elderly patients admitted to the Chinese PLA General Hospital between 2007 and 2022. Early recovery was defined as renal function recovery documented a week after AKI diagnosis. Recovery of AKI was defined as being alive for over 7 days and when the patient's serum creatinine level returned to below 1.2 times, the baseline value for at least 2 days post-AKI. A total of 1395 elderly patients were enrolled for eventual analysis; their median age was 88 years. Using the Kidney Disease Improving Global Outcomes stage, 51.7%, 25.9%, 22.4% were in stages 1, 2, and 3, respectively. Four patterns are observed. The most common (423; 30.3%) patients showed late recovery after day 7. The remaining patients (337; 24.2%) had never fully recovered; early recovery was sustained (230; 16.5%) during follow-up, but almost as many patients with early recovery had one or more recurrences (255; 18.3%). Patients with different phenotypes had distinct outcomes, and the 1-year survival rates were 79% for early sustained recovery, 64% for recurrent AKI, and less than 41% for patients who had never recovered. Relative to early sustained recovery, late recovery was related to a 2-fold increase in the 1-year mortality. Four different recovery phenotypes were detected based on the clinical course seven days after AKI diagnosis. These phenotypes contribute to the identification of patients suitable for treatment.
Li et al. (Wed,) studied this question.