Pre-stroke dementia and in-hospital outcomes in the Chinese Stroke Center Alliance.

Abstract

Little is known about the impact of prevalent dementia on in-hospital outcomes of patients with incident stroke in China. Using data from the Chinese Stroke Center Alliance (CSCA), we aim to quantify the prevalence of pre-stroke dementia and whether this group is at higher risk of adverse in-hospital outcomes compared to those without pre-stroke dementia. We used multivariable logistic regression models to assess the associations between pre-stroke dementia and ambulation by day 2, in-hospital mortality, in-hospital complications, and being discharged home. Covariates included age, sex, comorbidities [dyslipidemia, atrial fibrillation, peripheral vascular disease (PVD), smoking, and alcohol use], medication history (antiplatelet drugs or lipid-lowering drugs), stroke severity [measured by the National Institute of Health Stroke Scale (NIHSS)], administration of intravenous tissue plasminogen activator (IV tPA) within 4.5 hours of stroke onset, and receipt of deep vein thrombosis (DVT) prophylaxis if indicated. In the final analytic sample of 559,070 ischemic stroke patients with no prior stroke history enrolled across 1,476 hospitals, those with pre-stroke dementia (n=1,511; 0.3%) were older and more likely to be female. Despite having received similar treatment, patients with pre-stroke dementia had lower odds of ambulating by day 2 [odds ratio (OR) =0.69; 95% confidence interval (CI): 0.62-0.78], higher odds of in-hospital mortality (OR =2.01; 95% CI: 1.35-2.99) or complications (OR =2.17; 95% CI: 1.93-2.44), and lower odds of being discharged home compared to those without pre-stroke dementia (OR =0.71; 95% CI: 0.62-0.83). Worse in-hospital outcomes among patients with pre-stroke dementia may be explained by pre-existing cognitive impairment that limited their ability to advocate for care needs. Further research is needed to determine whether a different care pathway or additional attention from clinicians is necessary for patients with pre-stroke dementia.