Early Versus Late-Onset Acute Kidney Injury in Cardiogenic Shock: Differential Prognostic Implications

Background Acute kidney injury (AKI) is common in cardiogenic shock (CS) and increases mortality, but the prognostic impact of onset timing in infarct-related CS is unclear. We examined whether early versus late AKI onset is associated with differences in patient characteristics and outcomes. Methods In this retrospective cohort study, 369 patients with infarct-related CS were classified by AKI timing within the first 96 h of admission: early (≤ 48 h) or late (> 48 h), according to KDIGO criteria. Clinical, hemodynamic, and inflammatory parameters and outcomes were compared. Multivariable logistic regression identified independent predictors of early AKI and in-hospital mortality. Results AKI occurred in 143 patients (42.8%), with 56.6% early-onset. In-hospital mortality was higher with early AKI than late AKI (71.6% vs. 54.8%; absolute difference 16.8%, 95% CI 3.1–30.5; p = 0.018). Early AKI patients had higher lactate at admission (median 4.3 vs. 3.1 mmol/L; p = 0.028), greater norepinephrine requirements (0.34 vs. 0.21 µg/kg/min; p = 0.044), and more frequent mechanical ventilation (81.5% vs. 61.3%; p = 0.011). In multivariable analysis, early AKI independently predicted in-hospital mortality (adjusted OR 2.12, 95% CI 1.16–3.87; p = 0.015), and was associated with baseline creatinine (OR 5.68 per 1 mg/dL, p = 0.008) and 24-h lactate (OR 2.67 per mmol/L, p < 0.001). Conclusions In infarct-related CS, AKI within 48 h marks a high-risk hemodynamic phenotype with markedly increased mortality, driven by renal vulnerability and early hypoperfusion. Incorporating AKI timing into risk stratification may help target early renoprotective interventions.