Clinical Types and Outcome of Minor Ischemic Stroke in Northern China: A Retrospective Cohort Study

Abstract
Background: As a common and high incidence of disease, the minor ischemic stroke (MIS) has become an important public health problem. The aim of this study was to address whether patients with MIS have different types and outcome in the elderly in northern China. Methods: A retrospective cohort of consecutive patients was selected for study; all registered neurologic outpatients of the tertiary teaching hospital in northern Jiangsu, China between February, 2011 and February, 2012. A total of 433 outpatients, clinically only having had an initial visit and a MRI study of the brain, were enrolled. Results: Of 433 outpatients, 247 (57.0%) patients with MIS were diagnosed. The clinical types of MIS included stable MIS in 58.3%, acute progressive MIS in 5.3%, and chronic progressive MIS in 36.4% of patients. After adjusted Odd ratio (OR), only aged (OR, 1.0; 95% confidence interval [CI], 1.007 - 1.087, p = 0.021), episode duration (OR, 1.8; 95% CI, 1.011 - 1.024, p = 0.001), initial number of MIS (OR, 1.1; 95% CI, 1.047 - 1.207, p = 0.001), and infarcts volume (OR, 1.8; 95% CI, 1.253 - 2.681, p = 0.002) were independently associated with stable MIS and progressive MIS. Total survival was favorable among groups (p = 0.094), but the followed mRS score was significantly higher among those progressive MIS than those stable MIS (2.3 ± 1.0 vs 0.1 ± 0.3, p < 0.001). Conclusion: MIS had a very high prevalence and different clinical types. Stable MIS is a benign stroke, whereas those progressive MIS may have long-term instability or acute and chronic progressive trend. This information is important in prospectively determining outcome of MIS and in patient treatment.