Sepsis-Associated Acute Kidney Disease and Long-term Kidney Outcomes

Rationale & Objective: Sepsis-associated acute kidney injury often leads to acute kidney disease (AKD), predisposing patients to long-term complications such as chronic kidney disease (CKD), kidney failure with replacement therapy (KFRT), or mortality. Risk stratification of patients with AKD represents an opportunity to assist with prognostication of long-term kidney complications. Study Design: Single-center retrospective cohort. Setting & Participants: 6,290 critically ill patients admitted to the intensive care unit with severe sepsis or septic shock. Patients were separated into cohorts based on incident acute kidney injury or not, and survivors identified who were alive and free of KFRT up to 90 days. Predictors: AKD stage (0A, 0C, or >= 1) using the last serum creatinine concentration available by discharge or up to 90 days postdischarge. Outcome: Time to development of incident CKD, progression of CKD, KFRT, or death. Analytical Approach: Multivariable Cox proportional hazards models. Results: Patients surviving kidney injury associated with sepsis often fail to return to baseline kidney function by discharge: 577/1,231 (46.9%) with stage 0C or 1 or greater AKD. AKD stage was significantly associated with the composite primary outcome. Stages 0C AKD and 1 or greater AKD were significantly and progressively associated with the primary outcome when compared with stage 0A AKD (adjusted HR [aHR], 1.74; 95% CI, 1.32-2.29, and aHR, 3.25; 95% CI, 2.52-4.20, respectively). Additionally, stage 1 or greater AKD conferred higher risk above stage 0C AKD (aHR, 1.87; 95% CI, 1.44-2.43). CKD incidence or progression and KFRT, more so than mortality, occurred with greater frequency in higher stages of AKD. Limitations: Retrospective design, single center, exclusion of patients with KFRT within 90 days of discharge, potential ascertainment bias, and inability to subclassify above AKD stage 1. Conclusions: Risk stratification using recommended AKD stages at hospital discharge or shortly thereafter associates with the development of long-term kidney outcomes following sepsis-associated acute kidney injury.

Automated summary

Risk stratification of patients with sepsis-associated acute kidney injury, using AKD stages, is significantly associated with long-term kidney outcomes. AKD stage 0C and stage 1 or greater are significantly associated with the primary outcome. Stage 1 or greater AKD presents higher risk than stage 0C AKD, with CKD incidence, progression, and KFRT occurring more frequently in higher AKD stages than mortality.