Inflammatory Indices and Clinical Indication for Hospitalization in Patients Presenting with Acute Psychosis

Objective: Growing evidence suggests that inflammatory mechanisms may contribute to psychotic disorders, and hematologic indices derived from routine complete blood count parameters may offer practical biomarkers in emergency settings. This retrospective, single-center, observational study evaluated the relationship of the systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and pan-immune-inflammation value (PIV) with clinical outcomes in adults presenting to the emergency department with acute psychosis.
Material and Methods: Adult patients presenting between January 1, 2021, and December 31, 2023, were included. The primary outcome was the clinical indication for hospitalization after emergency department assessment, defined as either completed admission or refusal of a recommended admission. Patients discharged with-out a recommendation for admission constituted the no-indication group. Secondary outcomes were inpatient length of stay, emergency department length of stay, and 12-month revisits.
Results: A total of 260 patients were analyzed (mean age, 36.89±12.29 years; 43.1% female). A clinical indication for hospitalization was documented in 201 pa-tients (77.3%): 176 were admitted, and 25 declined the recommended admission. SII was higher in the indication group in the unadjusted analysis (1084.57±828.79 vs 884.53±590.99; p=0.045), but this association was not retained after multivariable adjustment. SIRI and PIV were not associated with the clinical indication for hospitali-zation. ROC analysis showed limited discriminative performance for SII (AUC, 0.586; 95% CI, 0.523–0.646; p=0.041). No significant associations were found between the inflammatory indices and inpatient length of stay or revisit frequency.
Conclusion: Although SII showed a modest unadjusted association with the clinical indication for hospitalization, its limited discrimination and lack of an independent association after adjustment do not support its clinical use. These exploratory findings do not support SII, SIRI, or PIV as triage biomarkers in acute psychosis at present.

Keywords: Acute psychosis, biomarkers, clinical indication for hospitalization, disposition, emergency department, inflammatory indices