What Is a Minor Stroke?

Abstract

Background and Purpose— The term “minor stroke” is often used; however a consensus definition is lacking. We explored the relationship of 6 “minor stroke” definitions and outcome and tested their validity in subgroups of patients. Methods— A total of 760 consecutive patients with acute ischemic strokes were classified according to the following definitions: A, score ≤1 on every National Institutes of Health Stroke Scale (NIHSS) item and normal consciousness; B, lacunar-like syndrome; C, motor deficits with or without sensory deficits; D, NIHSS ≤9 excluding those with aphasia, neglect, or decreased consciousness; E, NIHSS ≤9; and F, NIHSS ≤3. Short-term outcome was considered favorable when patients were discharged home, and favorable medium-term outcome was defined as a modified Rankin Scale score of ≤2 at 3 months. The following subgroup analyses were performed by definition: sex, age, anterior versus posterior and right versus left hemispheric stroke, and early (0 to 6 hours) versus late admission (6 to 24 hours) to the hospital. Results— Short-term and medium-term outcomes were most favorable in patients with definition A (74% and 90%, respectively) and F (71% and 90%, respectively). Patients with definition C and anterior circulation strokes were more likely to be discharged home than patients with posterior circulation strokes ( P =0.021). The medium-term outcome of older patients with definition E was less favorable compared with the outcome of younger ones ( P =0.001), whereas patients with definition A, D, and F did not show different outcomes in any subgroup. Conclusions— Patients fulfilling definition A and F had best short-term and medium-term outcomes. They would be best suited to the definition of “minor stroke.”

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

“…However, we have confirmed that overall survival rate in patients with MIS in the out-patient clinic during the follow-up period of 6 months is favorable (99.2%). Our view is consistent with more studies reported survival of MIS [3] [10]. Although there are one to two reports described poor survival [26] [27], we still believe that the survival status in patients with MIS have a favorable trends.…”

“…However, in an out-patient setting from the county town and villages in patients over the age of 40 years, our findings show a 57.0% rate of MIS and with different types in clinical. Some MIS with a stable course and a good prognosis have been reported [3] [4]. Within our out-patient clinic setting, the stable MIS occurred with greatest frequency, accounting for 58.3% of patients.…”

“…In accordance with clinical features and followed mRS score, two types of MIS were delineated: 1) Stable MIS: those MIS with a stable or benign course [3] [4], and with a followed mRS score of 0 -1; 2) Progressive MIS: including two subtypes (a) acute progressive MIS: any symptoms rapidly progress or recurrent new symptoms, and lesions rapidly evolution or extension during the first 7 days after onset; or adds at least 1 point to scores by National Institutes of Health Stroke Scale (NIHSS) [8], and with a followed mRS score of 2 -6 at 6 months follow-up; (b) chronic progressive MIS: symptoms slowly occurring for more than a few months; frequent transient symptoms or new ischemic event tend to progress slowly; or with chronic progressive neurologic decline and normal pressure hydrocephalus [12], or chronic or acute-onchronic white matter ischaemia [13], and with a mRS score of 2 -6 at 6 months follow-up.…”

“…In such studies, small stroke or lacunar stroke was usually considered favorable short-term outcome and having had a very low NIHSS score, so this is why it is considered a MIS [3] [4]. In fact, it has been shown that MIS may also result from atheromatous stenosis or occlusion of larger arteries [4] [5] [6], in which the presence of one or more lesions may be associated with a rapidly progressive deficit [7] [8] [9], or even carry a worse prognosis [9] [10].…”

Minor ischemic stroke

“…2 Since extensive functional and cognitive testing could not be routinely performed in the acute setting, most definitions used for minor stroke in analyses of outcomes are based on structured neurologic examinations, such as the itemized NIH Stroke Scale (NIHSS). 3 Most definitions used in prior studies of minor stroke did not include the effect on the patient's ability to perform functional and cognitive tasks. A notable exception is the definition used in the ongoing Phase IIIB, DoubleBlind, Multicenter Study to Evaluate the Efficacy and Safety of Alteplase in Patients with Mild Stroke: Rapidly Improving Symptoms and Neurologic Deficits (PRISMS) study which, in addition to requiring an NIHSS of 5 or less, requires the consideration of the patient's ability to perform activities of daily living and return to work based on the observed deficits.…”