Prediction of late seizures after ischemic stroke using cognitive scores.

Background: Late seizures are well-known sequelae after stroke. Previous history of stroke and dementia is common etiology of epilepsy, however, the effect of cognitive impairment on late seizures has not been fully investigated. We investigated the clinical significance of cognitive scores in predicting the occurrence of post-stroke late seizures.

Methods: Adult patients with acute cerebral infarction were analyzed. Their cognitive function was evaluated using the Addenbrooke's Cognitive Examination (ACE)-III and the Japanese version of Montreal Cognitive Assessment (MoCA-J) within two weeks after stroke. Factors associated with late seizures and accuracy of cognitive scores to predict late seizures were analyzed.

Results: Of 45 patients enrolled (28 males, age 77.2 ± 8.5 years, mean ± SD), eight patients had late seizures within 123.8 ± 126.5 days after cerebral infarction. Cognitive evaluation was performed at 8.0 ± 3.9 days. ACE-III and MoCA-J scores were significantly lower in patients with late seizures than in those without late seizures (ACE-III: 27.5 ± 17.3 vs. 59.1 ± 27.2, MoCA-J: 7.6 ± 5.9 vs. 15.4 ± 8.6, p < 0.05, unpaired t-test). Receiver operating characteristic curve analysis revealed that area under curve of ACE-III was larger than that of MoCA-J and size of cerebral infarction. The optimum cut-off scores of ACE-III were ≤ 58.5 (Sensitivity: 1.00, specificity: 0.62) and ≤ 45.0 (0.88, 0.73). Kaplan-Meier estimates showed that each cut-off score significantly associated with late seizures. Sizes of infarcts and of cortical lesion were not significantly different between patients with and without late seizures. ROC curve and Kaplan-Meier survival analyses showed a significant association between size of infarct and late seizures, however, ACE-III scores more strongly associated with late seizures than the size of infarct did.

Conclusion: Cognitive scores, especially ACE-III, within two weeks after cerebral infarction can be useful for predicting post-stroke late seizures.