Stroke Unit Care: Does Ischemic Stroke Subtype Matter?

BACKGROUND: Stroke unit care improves outcomes following ischemic stroke. However, it is not known whether all ischemic stroke subtypes benefit equally from stroke unit admission. OBJECTIVE: To determine whether the benefit of stroke unit admission is similar among all ischemic stroke subtypes. Design, setting and patients Prospective cohort study including patients admitted with an acute ischemic stroke between July 2003 and September 2007 to stroke centers participating institutions in the Registry of the Canadian Stroke Network. Ischemic stroke subtype information was determined according to the modified Trial of Org 10 172 in Acute Stroke Treatment criteria and categorized as small vessel disease (lacunar), large artery atherosclerotic disease, cardioembolic, or other (including both other determined and undetermined causes). Main outcome measures The primary outcome measure was all-cause mortality at 30 days after stroke. Secondary outcomes were seven-day mortality and death or institutionalization at discharge. RESULTS: Among 6223 eligible patients with ischemic stroke admitted to regional stroke centers in Ontario, the mean age was 72 years and 52·4% were male. Overall 30-day mortality was 12·2%. The 30-day risk-adjusted mortality was lower for stroke unit care across all stroke subtypes (for lacunar stroke 3·0% vs. 5·3%; for large artery disease 7·5% vs. 14·5%; for cardioembolic 15·3% vs. 23·3%; and for other causes 8·9% vs. 15·9%). In multivariable analysis, after controlling for age, gender, medical comorbidities, and stroke severity, there was a significant reduction in stroke mortality associated with stroke unit admission in all stroke subtypes (odds ratio (95% confidence interval) for lacunar stroke 0·48 (0·27-0·88), for large artery atherosclerotic disease 0·39 (0·27-0·56), for cardioembolic 0·46 (0·36-0·59), and for other causes 0·45 (0·29-0·70)). The results remained similar after a sensitivity analysis excluding patients receiving palliative care, and a secondary analysis including 3215 patients with missing Trial of Org 10 172 in Acute Stroke Treatment classification. CONCLUSION: This study provides 'real-world' evidence that all ischemic stroke subtypes do benefit from a stroke unit admission regardless of the etiology. There is no justification for withholding access to stroke unit care based on stroke subtype.