Differences in long-term survival in two lacunar stroke types: a 15-year follow-up study in 782 cerebral infarct patients

Background: Mortality studies in lacunar (LAC) stroke are scarce and often characterized by short follow-up time, small patient groups and absence of a nonlacunar stroke group for comparison. Besides, there are no separate long-term prognostic data on LAC stroke subtypes. We performed a long-term mortality study in LAC stroke, subtyping two distinct phenotypes and including nonlacunar ischemic stroke for comparison.

Methods: We performed cross-sectional follow-up, determining survival status, after a median of 15.0 years, in 333 first-ever atherothrombotic (AT), 184 cardioembolic (CE) and 265 LAC strokes, distinguishing LAC stroke with (type 2) or without (type 1) asymptomatic LAC lesions on CT.

Results: End of follow-up mortality (in 30-day survivors) in LAC stroke (76.2%) was significantly lower than in CE (87.1%; OR 0.48, 95% CI 0.27-0.84), but not AT strokes (79.0%; OR 0.85, 95% CI 0.57-1.26), and was significantly lower in LAC type 1 than type 2 strokes (70.9 vs. 87.5%; OR 0.35, 95% CI 0.17-0.73). Kaplan-Meier analysis showed most favorable survival in LAC type 1 stroke. In the Cox regression analyses, LAC type 1 stroke appeared as an independent predictor of better survival versus LAC type 2, versus AT and versus CE strokes.

Conclusions: LAC stroke in general cannot be considered a 'benign' stroke type: only long-term survival in patients without concomitant asymptomatic LAC lesions is better than in large-vessel stroke. This difference in long-term survival between the two LAC stroke subtypes should be taken into account in prognostic counselling of individual LAC stroke patients.