Associations of the Oxfordshire Community Stroke Project subtypes with severity and outcomes of acute ischemic stroke

Abstract

Objective To investigate the associations of the Oxfordshire Community Stroke Project (OCSP) subtypes with severity and outcomes of acute ischemic stroke. Methods The inpatients with acute ischemic stroke were enrolled prospectively and divided into total anterior circulation infarct (TACI), partial anterior circulation infarct (PACI), posterior circulation infarct (POCI), and lacunar infarction (LACI) according to the OCSP classification. Demographic and baseline clinical data of the patients were recorded. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity, ≤8 was mild stroke and >8 was moderate to severe stroke. The clinical outcome was assessed at 90 d after onset with the modified Rankin Scale (mRS), and the favorable outcome was defined as mRS score 0-2, and the unfavorable one was defined as mRS score 3-5, death or cardiovascular event. Multivariate logistic regression analysis was used to determine the independent associations of the OCSP subtypes and stroke severity and outcomes. Results A total of 765 patients with acute ischemic stroke were enrolled, including 46 (6.0%) with TACI, 281 with PACI (36.7%), 229 (29.9%) with POCI, and 209 (27.3%) with LACI. There were 580 patients (75.8%) with mild stroke, and 185 (24.2%) with moderate to severe stroke; 17 were lost to follow-up, 513 (68.6%) had favorable outcomes, and 235 (31.4%) had unfavorable outcomes. There were significant differences between the baseline NIHSS scores and outcomes in each OCSP subtypes (all P<0.05), in which the baseline NIHSS score in TACI was the highest, the outcome was worst, and the proportion of patients with unfavorable outcome was 89.1%; there was significant difference in the baseline NIHSS scores between the PACI and the POCI (P<0.05), however, the proportion of patients with unfavorable outcome was not the case. Multivariate logistic regression analysis showed that TACI was an independent risk factor for moderate to severe stroke (odds ratio 84.881, 95% confidence interval 20.307-354.792; P<0.001) and unfavorable outcome (odds ratio 21.472, 95% confidence interval 8.362-55.136; P<0.001). Conclusion The OCSP subtypes were independently associated with the severity and outcomes of acute ischemic stroke. Key words: Stroke; Brain Ischemia; Severity of Illness Index; Risk Factors; Treatment Outcome