Introduction: Delirium, a disorder of attention and arousal, poses a large public health burden. Inattention and fluctuating cognitive status, two primary delirium symptoms, also occur when specialized right brain systems are impaired. Although right hemisphere stroke may predispose to delirium, systematic assessment methods and management of these patients are not yet available. We sought to characterize the incidence of delirium in right hemisphere stroke patients and explore whether stroke localization was associated with delirium.
Methods: We identified consecutive patients admitted to our stroke service with acute right hemisphere stroke over a 6-month period from our prospective stroke registry. We reviewed the medical record for core delirium symptoms: inattention, cognitive fluctuation, and either disorganized thinking, or altered level of consciousness. Delirium was assessed by systematically screening for trigger words. We compared baseline characteristics with Fisher’s exact and t-tests and assessed relation of stroke localization to delirium with logistic regression.
Results: Of 105 patients with acute right hemisphere stroke, 27 (26%) had delirium. Delirium patients were older (mean age 78 vs. 68, p<0.01), more likely to have dementia (30% vs. 5%, p<0.01) and prior stroke (52% vs. 28%, p=0.03). Median length of stay was longer (5 vs. 3 days, p<0.01), and discharge home less likely (37% vs. 64%, p=0.01) in those with delirium. Delirium patients more often had strokes involving the parietal lobe (44% vs. 17%, p<0.01). In a multivariable model, parietal localization strongly predicted incident delirium (OR 3.6 95%CI 1.1-11.3, p=0.03) adjusting for age, baseline NIHSS, and premorbid dementia.
Conclusion: The high delirium incidence we found supports routine delirium screening in acute stroke patients. Stroke localization may be one factor to incorporate into screening tools. Studies to prospectively identify and treat delirium in both right and left hemisphere stroke patients are warranted.