STROKE SUBTYPE IS AN AGE-INDEPENDENT PREDICTOR OF 1ST-YEAR SURVIVAL

The short-term outcome after acute stroke is known to be strongly dependent on stroke subtype, especially favoring patients having suffered a lacunar stroke. The value of stroke subtypes as long-term predictors of survival has not been firmly established. We therefore examined the 1-year survival from acute stroke in the Klosterneuburg Stroke Data Bank, which since 1988 systematically collects data on acute stroke patients treated in one center in Lower Austria. The cumulative survival of 398 consecutive patients (mean age 67.7 +/- SD 11.6) 1 year after a first-ever stroke was not only adversely related to age but also appeared to be age independent when compared according to stroke subtypes. The cumulative survival rates (CSR) ranged from 88.7 [95% confidence interval (CI): 82-92] for lacunar strokes (n = 107) to 68.1 (CI: 50-79) for atherothrombotic strokes (n = 69). Cardiogenic embolism (n = 68) showed a CSR of 72.1 (CI: 61-83) similar to the group of cryptogenic strokes (n = 121, CSR: 74.4, CI: 67-82). The CSR for primary intracerebral hemorrhage (n = 33) was 68.8 (CI: 53-85). It is concluded that the comparatively favorable prognosis of lacunar strokes must be recognized in trials designed to evaluate efficacy in terms of 1-year mortality. Furthermore, as cryptogenic stroke has an almost identical survival rate when compared to strokes caused by cardiogenic embolism it may be assumed that a considerable number of strokes for which no cause can be found are, in fact, cardiogenic embolic.