Common biomarkers of physiologic stress and associations with delirium in patients with intracerebral hemorrhage

Purpose: To examine associations between physiologic stress and delirium in the setting of a direct neurologic injury. Materials and methods: We obtained initial neutrophil-to-lymphocyte ratio (NLR), glucose, and troponin in consecutive non-comatose patients with non-traumatic intracerebral hemorrhage (ICH) over 1 year, then used multivariable regression models to determine associations between each biomarker and incident delirium. Delirium diagnoses were established using DSM-5-based methods, with exploratory analyses further categorizing delirium as first occurring 24 h (early-onset) or 24 h after presentation (later-onset). Results: Of 284 patients, delirium occurred in 55% (early-onset: 39% [n = 111]; later-onset: 16% [n = 46]). Patients with delirium had higher NLR (mean 9.0 +/- 10.4 vs. 6.4 +/- 5.5; p = 0.01), glucose (mean 146.5 +/- 59.6 vs. 129.9 +/- 41.4 mg/dL; p = 0.008), and a higher frequency of elevated troponin (>0.05 ng/mL; 21% vs. 10%, p = 0.02). In adjusted models, elevated NLR (highest quartile: OR 3.4 [95% CI 1.5-7.8]), glucose (>180 mg/dL: OR 3.1 [95% CI 1.1-8.2]), and troponin (OR 3.0 [95% CI 1.2-7.2]) were each associated with delirium, but only initial NLR was specifically associated with later-onset delirium and with delirium in non-mechanically ventilated patients. Conclusions: Stress-related biomarkers corresponding to multiple organ systems are associated with ICH-related delirium. Early NLR elevation may also predict delayed-onset delirium, potentially implicating systemic inflam-mation as a contributory delirium mechanism. (c) 2021 Elsevier Inc. All rights reserved.

Automated summary

This study found that in the setting of non-traumatic intracerebral hemorrhage, elevated NLR, high glucose levels, and increased troponin levels were associated with delirium. Elevated NLR specifically predicted delayed-onset delirium and delirium in non-mechanically ventilated patients.