Little is known regarding the association between acute in-hospital exposures such as delirium and long-term cognitive outcomes in patients with ICH.

To explore the risk of mild cognitive impairment or dementia (MCID) among intracerebral hemorrhage (ICH) patients who experienced in-hospital delirium.

We utilized State Inpatient and Emergency Department Databases for NY (2006 – 2014), CA (2005 – 2011), and FL (2005 – 2014), and established a cohort by selecting MCID-free patients with a primary diagnosis of ICH (ICD-9: 431) during a 2yr period. Patients with concurrent diagnoses of head trauma, arteriovenous malformation or missing linkage information were excluded. Delirium during the initial ICH event was tagged using a validated algorithm with high specificity for the confusion assessment method. The cohort was followed for MCID diagnoses. Patients that died within 90 days of ICH were excluded. We conducted time-to-event analyses and report cumulative incidence, 95% confidence interval (CI) and hazard ratios (HR) for risk of MCID among ICH patients with and without delirium.

A total of 18,083 ICH patients (age: 67.2, female: 47.6%, white: 59.1%) were included and were followed for up to 8yrs, resulting in 42,100 person-years. Patients who experienced delirium had a significantly higher comorbidity index and intensity of in-hospital treatment. Cumulative incidence (95% CI) for development of MCID was significantly higher among delirium patients (6.07, 5.05 – 7.30) as compared to non-delirium patients (4.07, 3.87 – 4.27). Likewise, risk of MCID among delirium patients was significant higher in the fully adjusted Cox proportional hazard model (HR, 95% CI: 1.42, 1.17 – 1.73).