Prognostic value and organ-specific correlations of admission MR-proADM in critically ill patients: a retrospective exploratory study

Background: Acute organ dysfunction is a primary driver of ICU mortality. As clinical scores often act as lagging indicators, early recognition of subclinical endothelial stress may be essential for timely intervention. This exploratory study investigated the association of mid-regional pro-adrenomedullin (MR-proADM)-a stable surrogate of the hormone adrenomedullin-as a potential early indicator of early organ failure. Methods: This retrospective, single-center study analyzed a heterogeneous cohort of 26 critically ill patients. Plasma MR-proADM levels were assessed at admission (t0) and daily for 5 days. The primary outcome was the correlation between admission MR-proADM and the 24-h SOFA score. Secondary outcomes included comparisons between septic and non-septic patients and between survivors and non-survivors. Results: Admission MR-proADM showed a moderate correlation with the 24-h SOFA score (rho = 0.488; p = 0.021), with the most prominent associations observed within the cardiovascular and renal SOFA domains. In the septic subgroup, MR-proADM levels were higher than in non-septic patients (10.90 [IQR 5.91-19.00] vs. 1.30 [IQR 0.74-2.53] nmol/L, p < 0.001); ROC analysis yielded an AUC of 0.88 (95% CI 0.73-1.00; p < 0.001), although this estimate should be interpreted descriptively given the small number of septic cases. Despite the low number of mortality events (n = 4), higher admission MR-proADM values were observed in non-survivors than in survivors, although this finding remains preliminary. Furthermore, admission MR-proADM levels showed positive correlations with procalcitonin at each individual timepoint during the first five ICU days (p < 0.001 at each timepoint). Conclusions: Within the limits of this small cohort, MR-proADM might provide a biological window into incipient organ dysfunction. Its possible role in supporting clinical assessment of sepsis and risk stratification-particularly regarding hemodynamic and renal dysfunction-remains strictly hypothesis-generating and requires validation in larger, prospective multicenter studies.