Prognostic value of dynamic KDIGO staging in acute kidney injury after acute heart failure: a doubly robust analysis

Acute kidney injury (AKI) is a frequent complication in acute heart failure (AHF) patients, yet few studies have examined the prognostic implications of different dynamic KDIGO AKI stages in this population. This retrospective cohort study aimed to rigorously investigate the impact of dynamic KDIGO AKI staging on outcomes in ICU patients with AHF using robust statistical methods like propensity score matching and doubly robust analysis. Utilizing the MIMIC-IV database of 5136 adult AHF patients from 2008 to 2022, doubly robust analysis revealed no significant differences in 28-day, 180-day, and 1-year mortality between non-AKI and mild AKI groups. However, moderate-to-severe AKI had significantly higher mortality at all timepoints compared to normal or mild AKI. Patients exhibiting mild AKI, termed "subclinical AKI" as their prognosis often parallels non-AKI, face a markedly worsened outlook if their condition progresses to moderate-to-severe AKI during hospitalization. However, it is worth noting that further sensitivity analysis showed that in patients with AHF as the first diagnosis, transient AKI caused by intensive decongestion therapy and other interventions did not have a significant impact on long-term outcomes.