Delirium Risk Factors and Associated Outcomes in a Neurosurgical Cohort: A Case-Control Study

Abstract

Objective: There are limited reports examining delirium in cohorts of neurosurgical patients across inpatient settings without separation based on subspecialty distinction. It is of interest to identify consistent delirium risk factors across various cranial pathologies and inpatient settings that will inform future interventional studies.

Methods: Delirium rates, patient and hospitalization risk factors, and clinical outcomes in 235 patients undergoing a cranial procedure were examined in a retrospective fashion.

Results: Fifty-two (22.1%) patients experienced delirium during their hospital stay. Patient factors predictive of delirium on univariate logistic regression were older age, a diagnosis of hydrocephalus or intracranial infection, transfer from an outside hospital, and admission through the emergency department. Hospitalization factors predictive of delirium included longer length of intensive care unit (ICU) stay, abnormal sodium values preceding delirium, a new postoperative infection, and the presence of a neurologic deficit. Using recursive partitioning, age ≥72.56 years and ICU length of stay ≥5 days were identified as critical thresholds for predicting delirium (odds ratio [OR] 4.61 and 18.2, respectively). On multivariate logistic regression analysis, age (unit OR 1.05), length of ICU stay (unit OR 1.2), and a neurologic deficit (OR 5.4) were predictive of delirium. Furthermore, delirium was also significantly associated with a longer length of admission as well as decreased likelihood for discharge home.

Conclusions: Delirium is a frequent occurrence after neurosurgery with older age, longer ICU stay, and a neurologic deficit being consistent risk factors across inpatient settings. These results help identify at-risk patients for delirium on a neurosurgical service to enact interventions preemptively.

Keywords: Cranial; Craniotomy; Delirium; Neurosurgery.