Individualized Dynamic Assessment of Mean Arterial Pressure in Hospitalized Older Patients with Acute Kidney Injury:...

Acute kidney injury (AKI) carries a high burden in hospitalized older adults. While mean arterial pressure (MAP) is a key modifiable factor, the prognostic value of its dynamic, individualized assessment beyond static thresholds remains poorly defined in this population.

In this retrospective cohort of 1248 hospitalized patients aged ≥65 years with AKI, we proposed and validated a three-dimensional hemodynamic assessment framework, evaluating: (1) the absolute MAP value at AKI onset (MAP_onset); (2) the relative change from patient-specific baseline (MAP change rate); and (3) the time of recovery to baseline. We defined distinct hemodynamic phenotypes and assessed their association with major adverse kidney events within 90 days (MAKE-90) using Cox regression. The incremental predictive value was evaluated with random forest models.

Both MAP_onset ≤65 mmHg (HR 1.33, 95% CI 1.05-1.69) and a decline in MAP of ≥10% from baseline (HR 1.26, 95% CI 1.03-1.54) independently predicted MAKE-90. Crucially, failure to recover within 72 hours was associated with a higher risk (HR 1.71, 95% CI 1.37-2.15). The integrated phenotype of severe initial hypotension with delayed recovery identified patients with the poorest prognosis (HR 1.72, 95% CI 1.36-2.17). Incorporating these dynamic parameters significantly improved the prediction of MAKE-90 (AUC increased from 0.71 to 0.76).

This study suggests that a dynamic, individualized MAP assessment might refine risk stratification beyond static thresholds in hospitalized older adults with AKI. Internal evaluation of the integrated dynamic phenotype showed improved predictive performance for adverse outcomes. However, given the retrospective design and substantial potential for confounding, these findings are exploratory. They require rigorous external validation in prospective cohorts before any consideration for clinical application.