Seizures after cerebrovascular events: Risk factors and clinical features

Open AccessPublished:February 14, 2013DOI:https://doi.org/10.1016/j.seizure.2013.01.014

      Abstract

      Background

      Epileptic seizures are well known sequelae of patients with stroke but only little is known about the different risk factors and about the influence of the different types of stroke including sinus thrombosis and bleedings on developing such seizures. Further, the association of post-stroke seizures and conventional vascular risk factors has not been evaluated to date.

      Methods

      We performed a cohort study on a sample of 593 consecutive patients with different types of cerebrovascular events. In 421 patients, sufficient data were obtained in a personal interview over a mean observation period of 30 months. Data regarding the clinical history were recorded from the patients’ charts.

      Results

      The total prevalence of epileptic seizures was 11.6%, the total annual risk was 4.6%. We detected the following significant risk factors: younger age at stroke; higher NIH stroke scale score; any coagulopathy. TIA was found significantly less frequent as a cause of seizures as compared to infarction, bleeding, and sinus thrombosis. Patients with bleeding (14.3%) and with sinus thrombosis (16.3%) were significantly more frequent in the seizure group than in the non-seizure group (6.7% and 1.6%, respectively). The location of stroke, including cortical versus subcortical, did not influence the risk of seizures. The majority of patients developed secondary generalized seizures (57.1%). In adjusted analyses, the two major risk factors for post-stroke epilepsy were a higher NIH stroke scale and a sinus thrombosis as the initial cerebrovascular event. Common lifestyle, vascular, and metabolic risk factors of stroke and for dementia were not associated with the development of seizures.

      Conclusions

      In conclusion, our data show that epileptic seizures occur in particular after major strokes and in sinus thrombosis. Interestingly, conventional vascular risk factors were not associated with the occurrence of post-stroke seizures. Considering the risk for seizures after certain types of cerebrovascular events might help to early identify patients for anticonvulsive treatment. In the future, it should be investigated whether these patients might benefit from pre-emptive anticonvulsant treatment.

      Keywords

      1. Introduction

      Stroke is the most common risk factor for seizures in the elderly population accounting for 39–45% of all seizures.
      • Roberts M.A.
      • Godfrey J.W.
      Epileptic seizures in the elderly. I. Aetiology and type of seizure.
      • Sung C.
      • Chu N.
      Epileptic seizures in elderly people: aetiology and seizure type.
      • Brodie M.J.
      • Kwan P.
      Epilepsy in elderly people.
      In an ageing society and with further improvement in stroke treatment, it becomes crucial to find methods for the prevention of seizures which have considerable social and psychological impact on the patients.
      • Myint P.K.
      • Staufenberg E.F.A.
      • Sabanathan K.
      Post-stroke seizure and post-stroke epilepsy.
      Some epidemiological studies have been published regarding seizures after stroke but they differ in number of patients, inclusion criteria, time of follow up, and diagnostic methods. Many studies have examined intracerebral haemorrhage (ICH), subarachnoid haemorrhage (SAH), and ischaemic stroke. There is, however, not much data concerning the development of seizures after other cerebrovascular events including transient ischaemic attack (TIA), different types of bleeding, and intracranial venous thrombosis (IVT).
      • Myint P.K.
      • Staufenberg E.F.A.
      • Sabanathan K.
      Post-stroke seizure and post-stroke epilepsy.
      In this hospital-based study, we aimed to find risk factors that contribute to the development of seizures and epilepsy after stroke in patients with different types of cerebrovascular events in univariate and multivariate analyses.

      2. Methods

      We evaluated all patients admitted to the Stroke Unit of the Department of Neurology, University of Münster between January 2003 and March 2010 for whom sufficient data were available in the database (n = 1611). Out of this number, we selected all patients with a first ever ischaemic stroke, TIA, ICH, SAH, or IVT. Only strokes with cerebral manifestation were included; strokes in cerebellar or brain stem location were excluded. Patients who had died while they were still in hospital were also excluded.
      For the resulting 593 patients, a detailed questionnaire was completed. One part of the questionnaire (baseline demographic and clinical data) was filled in with data obtained from a patient chart review and a clinical interview with the patients who were in hospital between October 2009 and March 2010 with a minimum duration of 2 weeks after stroke. In the other patients, a follow-up telephone interview either with the patients themselves or with relatives on behalf of those patients who could not communicate was conducted at least 3 months after the initial event. Only cases with a successful interview were finally included in the study (n = 421). The mean time of follow-up was 30 months (maximum 78 months). In 172 cases, the follow-up interview could not be carried out for the following reasons: the patients had died meanwhile and no relative was available (n = 21); the contact data in the charts were not correct any more (n = 139); they did not want to participate for personal reasons (n = 12). At the time of interview, 41 patients (9.7%) had died but sufficient data was obtained by relatives. The flow chart of the different reasons for patients enrolled or excluded is presented in Fig. 1.
      Seizures and epilepsies were classified according to the guidelines of the International League against Epilepsy (ILAE).
      • Commission on Epidemiology and Prognosis
      ILAE guidelines for epidemiologic studies on epilepsy.
      • Berg A.T.
      • Berkovic S.F.
      • Brodie M.J.
      • Buchhalter J.
      • Cross J.H.
      • van Emde Boas W.
      • et al.
      Revised terminology and concepts for organization of the epilepsies: report of the commission on classification and terminology.
      Early onset seizures were defined when they appeared within the first 7 days after stroke onset. Seizures were distinguished as being simple partial, complex partial, or generalized.
      Stroke severity was measured using the National Institute of Health (NIH) stroke scale which was obtained on admission to the hospital. In all cases, a CT or MRI brain scan were performed to diagnose the type of stroke. TIA was defined as symptoms lasting less than 24 h and no correlation to the symptoms in MRI and CT. Ischaemic stroke was diagnosed via plain CT, CT-angiography, CT-perfusion studies, or MRI with diffusion-weighted-imaging (DWI); bleeding was diagnosed via CT and MRI with DWI. IVT was also diagnosed via CT angiography or MRI angiography. TOAST criteria classification of ischaemic stroke was confirmed by carotid Doppler and CT angiography for ‘macroangiopathic stroke’, by transoesophageal echocardiography for ‘cardioembolic strokes’, and by CT/MRI scan (stroke size less than 15 mm) and absence of significant findings in the other two diagnostic tools for ‘microangiopathic stroke’. Further, events were classified as ‘other defined aetiology’ (e.g., cervical artery dissection) and of ‘unknown origin’ if none of the diagnostic approaches leads to inclusion in one of the aforementioned categories. Strokes were subclassified as having occurred in the anterior circulation if they occurred in the middle or anterior cerebral artery territory and in the posterior circulation if they had occurred in the vertebrobasilar territory. If a stroke had occurred in both it was excluded from this analysis in order to obtain homogenous subgroups. Only strokes clearly located in one of the two hemispheres were included in the respective analysis.
      Statistical analysis was performed using SPSS version 18. In the univariate analysis, categorical variables were compared using χ2-test and Fisher's exact test (if applicable). For parametric variables, we described arithmetic mean and standard deviation. The significance of differences between two groups was tested by Mann–Whitney U test. For multivariate analysis, a logistic regression model (backward Wald) was used. For this model, we included factors that showed significant influence on seizure development in univariate analysis and allowed to test a group which was large enough to perform a logistic regression model. Significance level was set at p = 0.05.

      3. Results

      Out of the 421 patients finally enrolled, 53.2% (n = 224) were male and 46.8% (n = 197) were female. The mean age was 64.8 ± 15.1 years. In total, 9.7% (n = 41) had deceased at the time of the interview but sufficient data was available. The diagnoses were as follows: TIA, n = 64 (15.2%); ischaemic stroke, n = 311 (73.9%); ICH, n = 32 (7.6%); IVT, n = 14 (3.3%). Patients who developed secondary ICH were included with the original aetiology (ischaemic stroke/IVT). N = 49 patients (11.6%) developed at least one epileptic seizures. The patients’ characteristics can be seen in Table 1. The calculated annual risk to develop a seizure was 4.6% for the total sample and 4.1% for ischaemic stroke.
      Table 1Characteristics of the total patients sample (n = 421).
      Patients with at least one seizure11.6%
      Age (in years)64.8 ± 15.1
      Sex
       Female46.8%
       Male53.2%
      Lifestyle
       BMI25.9 ± 4.1
       Smoking (time of interview)11.0%
       Ex smokers42.6%
       Drinking alcohol (time of interview)30.6%
       Ex drinking alcohol8.6%
      NIH score4.7 ± 5.1
      Type of cerebrovascular event
       TIA15.2%
       Ischaemic stroke73.9%
       ICH7.6%
       IVT3.3%
      Type of ischaemic stroke (TOAST criteria)
       Cardiac origin15.2%
       Microangiopathic4.8%
       Macroangiopathic20.6%
       Other defined6.4%
       Unknown38.9%
       Multiple14.5%
       Cortical involvement of stroke15.7%
      Rehabilitation
       Ambulatory5.5%
       Inpatient rehabilitation57.2%
       No rehabilitation37.3%
      The results of the univariate analysis for all variables regarded as potential risk factors for seizure development are presented in Table 2. Patients who developed seizures were significantly younger, had a significantly higher NIH stroke scale score, and received significantly more often an inpatient rehabilitation than patients without a seizure. Surprisingly, pre-existing cardiac conditions were significantly more frequent in patients without seizures than in patients with seizures. However, in the subgroup of pre-existing cardiac conditions the existence of coagulopathy was significantly more common among patients with seizures (8.2% compared to 1.3%; p = 0.013, OR 6.5, 95% CI 1.7–25.2) while patent foramen ovale (PFO) was less frequent in the seizure group (2.0% compared to 11.6%; p = 0.044, OR 0.2, 95% CI 0.0–0.6). All other risk factors were not significantly different in the two groups.
      Table 2Univariate analysis of stroke risk factors for development of epileptic seizures.
      Seizures (n = 49)No seizures (n = 372)pOR95% CI
      Sex (%)
       Female11.788.31.0001.00.6–1.8
       Male11.688.4
      Age (in years)56.6 ± 16.565.9 ± 14.6<0.001
      BMI25.7 ± 4.125.9 ± 4.10.526
      Smokers (%)
       Yes16.310.20.2371.60.7–3.7
       No83.789.8
      Ex-smokers (%)38.837.60.6181.20.6–2.3
      Drinking alcohol (%)24.531.50.4100.70.4–1.4
      NIHSS stroke score7.7 ± 6.14.3 ± 4.90.001
      Pre-existing conditions (%)
      Cardiac (any)75.587.10.0470.50.2–0.9
       Hypertension63.369.90.4110.70.4–1.4
       Atrial fibrillation12.222.80.0990.50.2–1.2
       Coronary heart disease4.111.30.1410.30.1–1.4
       Myocardial infarction2.08.60.1550.20.0–1.7
       Atrial septum aneur.03.80.3871.00.9–1.0
       PFO2.011.60.0440.20.0–1.2
       Dilatative cardiomyop.2.01.10.4631.90.2–17.5
       Cardiac valvulopathy2.03.21.0000.60.1–4.9
       Coagulopathy8.21.30.0136.51.7–25.2
      Metabolic (any)57.153.50.6511.20.6–2.1
       Diabetes18.416.90.8401.10.5–2.4
       Hypercholesterolaemia20.426.30.4860.70.4–1.5
       Obesity12.26.50.1422.00.8–5.2
       Hyperlipidemia14.313.20.8231.10.5–2.6
       Elevated Lp(a) levels2.02.71.0000.80.1–6.0
       Hyperuricaemia03.00.6251.00.9–1.0
       Hyper-homocysteinemia00.81.0001.00.9–1.0
      Degenerative CNS disorder01.61.0001.00.9–1.0
      Dementia02.70.6141.00.9–1.0
      Familial history (%)
       Stroke28.628.81.0001.00.5–1.9
       Epilepsy6.15.70.7521.10.3–3.8
      Among the subjects with seizures, 4.1% had TIA compared to 16.7% in the non-seizure group, 65.3% had ischaemic stroke compared to 75.0% in the non-seizure group. Patients with bleeding (14.3%) and with IVT (16.3%) were significantly more frequent in the seizure group than in the non-seizure group (6.7% and 1.6%, respectively). TIA was significantly less frequent in patients with seizures compared to those with bleeding (p = 0.006; OR 8.7, 95% CI 1.7–22.7) and IVT (p < 0.001; OR 41.3, 95% CI 7.1–240.6). IVT was also more common in patients with seizures than ischaemic stroke (p < 0.001; OR 11.6, 95% CI 3.8–35.6) and bleeding (p = 0.038; OR 4.8, 95% CI 1.2–18.4).
      Ischaemic stroke was subsequently divided into different stroke aetiologies using the TOAST criteria. We found that 12.1% of the patients with seizures had stroke of cardiac origin compared to 31.7% in the non-seizure group. None of the patients with stroke of microangiopathic origin suffered from seizures while microangiopathic ischaemic stroke was seen in 5.3% of the cases without seizures. Macroangiopathic ischaemic stroke (thrombotic stroke) was seen in 36.4% of the patients who later developed seizures while this aetiology was responsible for only 19.2% of the strokes not followed by seizures thus being significantly more common than the other aetiologies (p = 0.006; OR 4.9, 95% CI 1.5–16.1). Strokes of other defined aetiology were found in 9.1% of the patients with seizures and in 5.7% of those without. The aetiology of the stroke was unknown in 42.4% of the patients who suffered from seizures and 38.1% in the group that did not have seizures.
      Neither cortical involvement nor multiple strokes were significantly more common among patients who developed seizures. Carotid circulation stroke was more common than basilar circulation stroke both in patients without and with epileptic seizures showing no statistical significance between them. Strokes that were limited to one hemisphere (left or right) were equally common in both groups. Detailed results can be seen in Table 3.
      Table 3Impact of stroke aetiology and stroke localization on the development of epileptic seizures.
      Seizures (n = 49)No seizures (n = 372)pOR95% CI
      Stroke aetiology (%)<0.001
      p=0.006, OR 8.7, 95% CI 1.7–22.7 for comparison TIA with bleeding.
      ,
      p<0.001, OR 41.3, 95% CI 7.1–240.6 for comparison TIA with IVT.
      ,
      p<0.001, OR 11.6, 95% CI 3.8–35.6 for comparison ischemic stroke with IVT.
      ,
      p=0.038, OR 4.8, 95% CI 1.2–18.4 for comparison bleeding with IVT.
       TIA4.116.7
       Ischaemic stroke65.375.0
       ICH14.36.7
       IVT16.31.6
      TOAST criteria (%)0.006
      For comparison of macroangiopathic and cardiac origin.
      4.91.5–16.1
       Cardiac12.131.7
       Microangiopathic05.3
       Macroangiopathic36.419.2
       Unusual9.15.7
       Unknown42.438.1
      Vascular territory (%)
       Carotid circulation only69.472.60.239
      Comparison between carotid and basilary territory.
      2.40.7–8.1
       Basilary circulation only6.115.3
       Right hemisphere40.842.50.729
      Comparison between right and left hemisphere.
      0.90.4–1.7
       Left hemisphere34.742.5
       MCA involvement only63.368.00.3641.50.7–3.3
       Multiple18.414.00.2451.70.8–3.8
       Cortical involvement26.815.00.0712.11.0–4.4
      a p = 0.006, OR 8.7, 95% CI 1.7–22.7 for comparison TIA with bleeding.
      b p < 0.001, OR 41.3, 95% CI 7.1–240.6 for comparison TIA with IVT.
      c p < 0.001, OR 11.6, 95% CI 3.8–35.6 for comparison ischemic stroke with IVT.
      d p = 0.038, OR 4.8, 95% CI 1.2–18.4 for comparison bleeding with IVT.
      e For comparison of macroangiopathic and cardiac origin.
      f Comparison between carotid and basilary territory.
      g Comparison between right and left hemisphere.
      Table 4 presents the characteristics of the seizures in the patient sample. Partial seizures were observed in 40.8%. Out of these, 55.0% were simple partial and 45.0% were complex partial. 57.1% patients had generalized seizures. In one case, classification of the seizure could not be evaluated based on the patient's history. Status epilepticus was found in 16.7% of the cases, 6.3% presented with Todd's paralysis. Electroencephalography (EEG) was performed by our department in 49% of the cases directly after a (suspicious) seizure. 8.3% had EEG patterns suggestive of epilepsy, 50.0% had other pathological EEG findings, while 41.7% had no abnormalities in EEG. Anticonvulsant drugs were used by 91.8%. Seizure freedom under medication was reached in 81.6%. Monotherapy was prescribed in 86.7% of the cases.
      Table 4Different characteristics of epilepsy and epileptic seizures in stroke patients (presented in %).
      Single seizure42.9
      Epilepsy57.1
      Early seizures46.9
      Late seizures53.1
      Classification (according to ILAE)
       Simple focal22.5
       Complex focal16.3
       Generalized (secondarily)57.1
       Unknown4.1
       Status epilepticus16.7
       Todd paralysis6.3
      EEG
       Epilepsy typical patterns8.3
       Other50.0
       No abnormalities41.7
      Anticonvulsant drugs
       Use of anticonvulsants91.8
       Seizure freedom under therapy81.6
      In Table 5, the differences between patients with early onset und late onset seizures (for definition see methods) are presented. Early onset seizures appeared in 5.5% of all cases. Of the patients with seizures, 46.9% had early onset seizures while 53.1% had late seizures accounting for 6.2% of all cases. Patients with early seizures had a significantly lower NIH stroke score on admission (4.3 ± 4.9 compared to 9.8 ± 6.0 for those with late seizures; p = 0.002). All patients with IVT and seizures had early onset seizures (p = 0.001, OR 0.4, 95% CI 0.3–0.6). Late onset seizures were significantly more common among patients with TIA, ischaemic stroke, or bleeding with cortical involvement (38.5% compared to 6.7% in the early seizure group; p = 0.003, OR 0.1, 95% CI 0.0–1.0). Cortical involvement was not specifically recorded for patients with IVT. Adjusted for cortical involvement in IVT, a rate of 39.1% in early seizures was recorded.
      Table 5Comparison of early versus late (i.e., 7 days or later after stroke) seizures in stroke patients.
      Early seizures (n = 23)Late seizures (n = 26)pOR95% CI
      Sex (%)
       Male52.253.81.0001.10.4–3.3
       Female47.846.2
      Age53.9 ± 18.759.0 ± 14.10.400
      Epilepsy39.173.10.0220.20.1–0.8
      Lifestyle factors
       BMI27.0 ± 4.924.5 ± 3.00.080
       Smoking (%)13.019.20.7060.60.1–3.0
       Ex smokers (%)40.052.40.5360.60.2–2.1
       Drinking alcohol (%)26.123.11.0001.20.3–4.3
       Ex drinking alcohol (%)11.821.70.6770.50.1–2.8
      NIH stroke score4.3 ± 4.910.3 ± 5.70.002
      Type of stroke (%)
       TIA4.33.81.0001.10.7–19.3
       Ischaemic stroke52.276.90.0820.30.1–1.1
       ICH8.719.20.4240.40.1–2.3
       IVT34.800.0010.40.3–0.6
       Multiple26.719.20.7011.50.3–6.9
       Cortical involvement6.738.50.0030.10.0–1.0
      Vascular territories (%)
       Anterior circulation86.784.01.0001.20.2–7.7
       Posterior circulation6.78.01.0000.80.1–9.9
       Left hemisphere46.740.00.7491.30.4–4.8
       Right hemisphere46.752.01.0000.80.2–2.9
      Pre-existing conditions (%)
       Cardiovascular65.284.60.1830.30.1–1.3
       Metabolic52.262.50.5720.70.2–2.1
      Familial disposition (%)
       Stroke17.438.50.1250.30.1–1.3
       Seizures8.73.80.5942.40.2–28.1
      Seizures (%)
       Focal39.144.00.7771.20.4–3.9
       Generalized60.956.0
       Status epilepticus8.724.00.2310.30.1–1.7
       Todd paresis9.14.00.5932.40.2–28.5
      EEG (%)0.883
       No pathologies44.440.0
       Epilepsy typical pattern11.26.7
       Other abnormalities44.453.3
      The differences between patients with post-stroke epilepsy and only one seizure are presented in Table 6. Out of all patients with a post-stroke seizure, 57.1% suffered from recurrent seizures, i.e., epilepsy. 73.1% of them were patients with late seizures (p = 0.022, OR 0.02, 95% CI 0.01–0.8). Patients who developed epilepsy had a mean age of 59.3 ± 13.2 years compared to 68.5 ± 7.9 for those with a single seizure (p = 0.040). None of the other parameters such as stroke type, vascular territory or pre-existing conditions were statistically significantly different. Also, in terms of seizure presentation such as type of seizure, status epilepticus, Todd's paralysis, or EEG findings, no statistically significant differences could be observed.
      Table 6Risk factors for developing epilepsy versus only one single seizure after stroke.
      Epilepsy (n = 28)Single seizure (n = 21)pOR95% CI
      Sex (%)
       Male57.133.30.1492.70.8–8.7
       Female42.966.7
      Age (years)59.3 ± 13.268.5 ± 7.90.040
      BMI26.5 ± 3.625.3 ± 2.30.342
      Smoking (%)21.49.50.4382.60.5–14.4
      Ex smokers (%)36.457.90.2170.40.1–1.5
      Drinking alcohol (%)14.338.10.0920.30.1–1.1
      NIH stroke score8.17 ± 5.64.2 ± 3.70.155
      Type of stroke (%)
       TIA3.64.81.0000.70.0–12.6
       Ischaemic stroke64.366.71.0000.90.3–3.0
       Bleeding17.99.50.6832.10.4–11.9
       IVT14.319.00.7100.70.2–3.2
       Multiple20.823.51.0000.90.2–3.8
       Cortical involvement20.835.30.4760.50.1–2.0
      Vascular territories (%)
       Anterior circulation91.376.50.3733.20.5–20.2
       Posterior circulation4.311.80.5650.30.0–4.1
       Left hemisphere43.541.21.0001.10.3–3.9
       Right hemisphere47.852.91.0000.80.2–2.9
      Pre-existing conditions (%)
       Cardiovascular82.166.70.3162.30.6–8.7
       Metabolic46.471.40.1440.50.1–1.2
      Family history
       Stroke25.033.30.5420.70.2–2.3
       Seizures3.69.50.5690.40.0–4.2
      Seizures (%)
       Focal32.155.00.1442.60.8–8.4
       Generalized67.945.0
       Status epilepticus25.05.00.1166.30.7–56.3
       Todd paralysis10.700.2620.60.4–0.7
      EEG (%)
       No pathologies43.837.50.861
       Epilepsy typical pattern6.312.5
       Other abnormalities50.050.0
      Early seizures39.160.40.0220.020.01–0.8
      Late seizures73.126.9
      We included age, NIH stroke score, type of stroke, and cardiac pre-existing conditions as factors in a multivariate analysis in order to evaluate independent risk factors for the development of seizures after stroke. The results are presented in Table 7. A higher NIH stroke score was a significant factor for the development of seizures (p = 0.001) with a slightly elevated risk with each additional point on the scale (OR 1.1, 95% CI 1.0–1.2). IVT was associated with an adjusted risk of 9.3 (95% CI 2.1–41.6, p = 0.004) to develop seizures when compared to all other types of stroke. In this model, no other aetiology was significantly and independently associated with the development of seizures. Also, the existence of vascular pre-existing conditions and age were not significant for seizure development after stroke. In another model, we looked for differences between ischaemic stroke of cardiac and macroangiopathic origin, age, NIH stroke score and pre-existing cardiac conditions. Here, the appearance of macroangiopathic stroke was a risk factor for seizure development (p = 0.002, OR 12.1, 95% CI 2.5–59.4). In this model, however, neither an elevated NIH stroke score nor age was significantly associated with seizure development.
      Table 7Multivariate analysis of risk factors for seizure development after stroke.
      pOR95% CI
      Type of stroke
       IVT vs. all other types0.0049.32.1–41.6
       Ischaemic vs. all other typesn.s.
       Bleeding vs. all other typesn.s.
       TIA vs. all other typesn.s.
       Age0.0871.00.9–1.0
       NIH stroke score0.0011.11.0–1.2
       Vascular pre-conditionsn.s.
      Ischaemic strokes only
       Macroangiopathic versus cardiogenic0.00212.12.5–59.4
       NIH stroke scoren.s.
       Age0.0521.00.9–1.0
       Vascular pre-conditionsn.s.

      4. Discussion

      The rate of seizures after stroke varies widely in the literature (2.7–42.8%) due to different inclusion criteria, study designs, and detection modes.
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      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      project suggested a cumulative risk of 11.5% for the development of seizures within 5 years. This corresponds well with our findings although we included IVT. In our study, the rate of SAH was relatively small (n = 5) which could explain the similar findings. Bladin et al.
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      found an incidence of 8.9% and Misirli et al.
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      reported an incidence of 10.6% also without IVT. De Reuck et al. included IVT but described only late onset seizures where they found no association.
      • De Reuck J.
      • Goethals M.
      • Vonck K.
      • Van Maele G.
      Clinical predictors of late-onset seizures and epilepsy in patients with cerebrovascular disease.
      This could be confirmed in our study, since all seizures after IVT were of early onset. Benbir et al.
      • Benbir G.
      • Ince B.
      • Bozluolcay M.
      The epidemiology of post-stroke epilepsy according to stroke subtypes.
      found a rate of 26.6% among IVT patients who developed epilepsy. In our study the rate for patients with IVT who developed epilepsy was 28.6%.
      We found that younger age was associated with the development of seizures in univariate analysis. This was supported in some studies
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      • Arboix A.
      • Garcia-Eroles L.
      • Massons J.B.
      • Oliveres M.
      • Comes E.
      Predictive factors of early seizures after acute cerebrovascular disease.
      whereas other authors either found no differences
      • Burneo J.G.
      • Fang J.
      • Saposnik G.
      Impact of seizures on morbidity and mortality after stroke: a Canadian multicenter cohort study.
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • Lancman M.E.
      • Golimstok A.
      • Norscini J.
      • Granillo R.
      Risk factors for developing seizures after a stroke.
      or stated that older patients
      • Burn J.
      • Dennis M.
      • Bamford J.
      • Sandercock P.
      • Wade D.
      • Warlow C.
      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      were more at risk of developing seizures. Aging brain undergoes degenerative and neuroplastic changes that lead to decreased excitability of the cortex. Given that the volume of cortical gray matter is higher in younger patients, it is easy to assume that these younger patients develop seizures more often. Nonetheless, age was not a significant risk factor in multivariate analysis of stroke types but when we looked at cardioembolic and macroangiopathic ischaemic stroke, age was a significant factor again. Stroke severity
      • Olsen T.S.
      • Hogenhaven H.
      • Thage O.
      Epilepsy after stroke.
      • Reith J.
      • Jorgensen H.S.
      • Nakayama H.
      • Raaschou H.O.
      • Olsen T.S.
      Seizures in acute stroke: predictors and prognostic significance.
      • Lamy C.
      • Domigo V.
      • Semah F.
      • Arquizan C.
      • Trystram D.
      • Coste J.
      • et al.
      Early and late seizures after cryptogenic ischemic stroke in young adults.
      is a long accepted predictive factor for the development of late seizures,
      • De Reuck J.
      • Goethals M.
      • Vonck K.
      • Van Maele G.
      Clinical predictors of late-onset seizures and epilepsy in patients with cerebrovascular disease.
      early seizures,
      • Arboix A.
      • Garcia-Eroles L.
      • Massons J.B.
      • Oliveres M.
      • Comes E.
      Predictive factors of early seizures after acute cerebrovascular disease.
      • Reith J.
      • Jorgensen H.S.
      • Nakayama H.
      • Raaschou H.O.
      • Olsen T.S.
      Seizures in acute stroke: predictors and prognostic significance.
      and epilepsy
      • Lossius M.I.
      • Ronning O.M.
      • Slapo G.D.
      • Mowinckel P.
      • Gjerstad L.
      Poststroke epilepsy: occurence and predictors – a long-term prospective controlled study (Akershus stroke study).
      • Strzelczyk A.
      • Haag A.
      • Raupach H.
      • Herrendorf G.
      • Hamer H.J.
      • Rosenow F.
      Prospective evaluation of a post-stroke epilepsy risk scale.
      but measurement of stroke severity was carried out with different instruments in different studies. We found that a higher NIH stroke scale score increases the risk for the development of seizures. This finding is supported by Bladin et al.,
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      while Burneo et al.
      • Burneo J.G.
      • Fang J.
      • Saposnik G.
      Impact of seizures on morbidity and mortality after stroke: a Canadian multicenter cohort study.
      found no significant differences in NIH stroke scores but only investigated ischaemic and haemorrhagic strokes. The higher rate of seizures in patients with inpatient rehabilitation treatment can be explained by the fact that patients with a more severe stroke are more likely to receive this procedure. In multivariate analysis of stroke subtypes, NIH stroke score was significantly associated with seizures, whereas in the setting of ischaemic strokes only, NIH stroke score was not significantly associated with seizures.
      In our study, IVT was associated with seizures in multivariate analysis when compared to all other stroke types. In most studies
      • Burneo J.G.
      • Fang J.
      • Saposnik G.
      Impact of seizures on morbidity and mortality after stroke: a Canadian multicenter cohort study.
      • Lancman M.E.
      • Golimstok A.
      • Norscini J.
      • Granillo R.
      Risk factors for developing seizures after a stroke.
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      • Burn J.
      • Dennis M.
      • Bamford J.
      • Sandercock P.
      • Wade D.
      • Warlow C.
      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      • Labovitz D.L.
      • Hauser A.W.
      • Sacco R.L.
      Prevalence and predictors of early seizure and status epilepticus after first stroke.
      seizures following ICH and SAH are significantly more common than after ischaemic stroke but these studies did not include TIA and IVT. We found a significantly lower rate of seizures in patients with bleeding compared to those with IVT in univariate analysis but no significantly higher rates of bleeding when compared to ischaemic stroke. In contrast to other studies,
      • Burn J.
      • Dennis M.
      • Bamford J.
      • Sandercock P.
      • Wade D.
      • Warlow C.
      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      • Benbir G.
      • Ince B.
      • Bozluolcay M.
      The epidemiology of post-stroke epilepsy according to stroke subtypes.
      • So E.L.
      • Annegers J.F.
      • Hauser W.A.
      • O’Brien P.C.
      • Whisnant J.P.
      Population-based study of seizure disorders after cerebral infarction.
      we did not find any significant difference in seizure occurrence with respect to left or right hemisphere or multiple infarction. However, seizures occurred clearly much more often after anterior circulation strokes.
      Szaflarski et al.
      • Szaflarski J.P.
      • Rackley A.Y.
      • Kleindorfer D.O.
      • Khoury J.
      • Woo D.
      • Miller R.
      • et al.
      Incidence of seizures in the acute phase of stroke: a population based study.
      used the NIH stroke score to measure stroke severity and found significantly higher NIH stroke scores in patients who had early seizures compared to those who did not develop seizures at all. The mean score in the patients with early seizures was notably higher than in our study. In our study, the NIH stroke scores are similar for patients with early onset seizures and patients without seizures but we used a 7-day interval to distinguish early seizures from late seizures and also included IVT. When adjusted for the 24-h interval, we see a mean score of 5.3 which is still lower than in the aforementioned study. In our study, all seizures that appeared after IVT were early onset seizures. Patients who had early onset seizures had significantly lower NIH stroke scores than those with late onset seizures.
      Furthermore, having cardiac pre-existing conditions resulted in a lesser incidence of seizures. Since in our study seizures appeared in a relatively young population, it is likely that this younger population had less cardiac pre-existing conditions. In multivariate analysis, cardiac pre-existing conditions failed to show significance concerning seizure development. Even though coagulopathy was significantly more frequent among patients with seizures, this finding was not included in multivariate analysis due to the small number of cases. Since coagulopathies are associated with IVT,
      • Moster M.L.
      Coagulopathies and arterial stroke.
      it is not surprising that the rate of seizure patients is higher in this group.
      No patients with dementia developed seizures in contrast to a study by Cordonnier et al.
      • Cordonnier C.
      • Henon H.
      • Derambure P.
      • Pasquier F.
      • Leys D.
      Influence of pre-existing dementia on the risk of post-stroke epileptic seizures.
      who found dementia to be an independent risk factor for late seizures. Also no metabolic pre-existing condition was significantly associated with seizure development supporting previous studies.
      • Burneo J.G.
      • Fang J.
      • Saposnik G.
      Impact of seizures on morbidity and mortality after stroke: a Canadian multicenter cohort study.
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • De Reuck J.
      • Goethals M.
      • Vonck K.
      • Van Maele G.
      Clinical predictors of late-onset seizures and epilepsy in patients with cerebrovascular disease.
      • Arboix A.
      • Garcia-Eroles L.
      • Massons J.B.
      • Oliveres M.
      • Comes E.
      Predictive factors of early seizures after acute cerebrovascular disease.
      • Reith J.
      • Jorgensen H.S.
      • Nakayama H.
      • Raaschou H.O.
      • Olsen T.S.
      Seizures in acute stroke: predictors and prognostic significance.
      Devuyst et al.
      • Devuyst G.
      • Karapanayiotides T.
      • Hottinger I.
      • Van Melle G.
      • Bogousslavsky J.
      Prodromal and early epileptic seizures in acute stroke. Does higher serum cholesterol protect?.
      stated that an elevated level of serum cholesterol protected against early seizures. Our results cannot confirm this finding. Familial disposition for stroke or epilepsy did not lead to a higher rate of seizures in the respective groups.
      In the multivariate analysis, we found that macroangiopathic stroke was more likely to be followed by seizures than strokes of cardiac origin. In addition, patients with probable cardioembolic focus either suffered less from seizures (in patients with PFO) or showed no differences compared to those without. In the literature, there are either no differences
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • Arboix A.
      • Garcia-Eroles L.
      • Massons J.B.
      • Oliveres M.
      • Comes E.
      Predictive factors of early seizures after acute cerebrovascular disease.
      • Bogusslavsky J.
      • VanMelle G.
      • Regli F.
      The Lausanne stroke registry: analysis of 1,000 consecutive patients with first stroke.
      • Dávalosa A.
      • De Cendraa E.
      • Molinsa A.
      • Ferrandizb M.
      • Lopez-Pousac S.
      • Genísa D.
      Epileptic seizures at the onset of stroke.
      observed or a higher rate of epileptic seizures for cardioembolic strokes
      • Meyer J.S.
      • Charney J.Z.
      • Rivera V.M.
      • Mathew N.T.
      Cerebral embolization: prospective clinical analysis of 42 cases.
      • Lesser R.P.
      • Lüders H.
      • Dinner D.S.
      • Morris H.H.
      Epileptic seizures due to thrombotic and embolic cerebrovascular disease in older patients.
      • Giroud M.
      • Gras P.
      • Fayolle H.
      • André N.
      • Soichot P.
      • Dumas R.
      Early seizures after acute stroke: a study of 1,640 cases.
      has been reported. It is noteworthy that the majority of the former positive studies were performed before modern neuroimaging and echocardiographic techniques became available.
      • Ryvlin P.
      • Montavont A.
      • Nighoghossian N.
      Optimizing therapy of seizures in stroke patients.
      It was a common believe that cortical involvement which is seen more often in cardioembolic strokes is a predictive factor for seizure development.
      • Berges S.
      • Moulin T.
      • Berger E.
      • Tatu L.
      • Sablot D.
      • Challier B.
      • et al.
      Seizures and epilepsy following strokes: recurrence factors.
      • Lancman M.E.
      • Golimstok A.
      • Norscini J.
      • Granillo R.
      Risk factors for developing seizures after a stroke.
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      • Strzelczyk A.
      • Haag A.
      • Raupach H.
      • Herrendorf G.
      • Hamer H.J.
      • Rosenow F.
      Prospective evaluation of a post-stroke epilepsy risk scale.
      • Labovitz D.L.
      • Hauser A.W.
      • Sacco R.L.
      Prevalence and predictors of early seizure and status epilepticus after first stroke.
      In our study, cortical involvement was more frequent in the seizure group but did not reach statistical significance in univariate analysis, and there are other studies
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • Burn J.
      • Dennis M.
      • Bamford J.
      • Sandercock P.
      • Wade D.
      • Warlow C.
      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      • Strzelczyk A.
      • Haag A.
      • Raupach H.
      • Herrendorf G.
      • Hamer H.J.
      • Rosenow F.
      Prospective evaluation of a post-stroke epilepsy risk scale.
      that support our finding. We hypothesize that subcortical strokes can cause cortical liability to develop seizures. Thus, stroke severity predicts the appearance of seizures more likely than the initial involvement of the cortex itself.
      Information about seizure characteristics is inconsistent in the literature because of different methods to differentiate seizure types. We found seizures to be more often generalized than partial. This is supported by Berges et al.
      • Berges S.
      • Moulin T.
      • Berger E.
      • Tatu L.
      • Sablot D.
      • Challier B.
      • et al.
      Seizures and epilepsy following strokes: recurrence factors.
      who found similar rates and Misirli et al.
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      who also found a higher rate of generalized seizures. Myint et al.
      • Myint P.K.
      • Staufenberg E.F.A.
      • Sabanathan K.
      Post-stroke seizure and post-stroke epilepsy.
      in contrast state that partial seizures account for 66% of the seizures but do not mention how they classified secondarily generalized seizures.
      The rate of status epilepticus in a study by Rumbach
      • Rumbach L.
      • Sablot D.
      • Berger E.
      • Tatu L.
      • Vuillier F.
      • Moulin T.
      Status epilepticus in stroke reports on a hospital-based stroke cohort.
      and Berges et al.
      • Berges S.
      • Moulin T.
      • Berger E.
      • Tatu L.
      • Sablot D.
      • Challier B.
      • et al.
      Seizures and epilepsy following strokes: recurrence factors.
      is 19% corresponding with our findings while Velioglu et al.
      • Velioglu S.
      • Ozmenoglu M.
      • Boz C.
      • Alioglu Z.
      Status epilepticus after stroke.
      found an incidence of only 9% but did not include SAH and IVT. While 50% of the patients with bleeding and seizure in our study developed status epilepticus, none of the patients with IVT had status epilepticus.
      It is very difficult to determine the characteristics of seizures via phone interview since classification often depends on patients’ observations. For example, it is very difficult to evaluate the percentage of true status epilepticus when use of benzodiazepines to terminate a seizure is included in this definition rather than just based on direct clinical observation as in the study of Velioglu et al.
      • Velioglu S.
      • Ozmenoglu M.
      • Boz C.
      • Alioglu Z.
      Status epilepticus after stroke.
      Yarnell
      • Yarnell P.R.
      Todd's paralysis: a cerebrovascular phenomenon?.
      postulated that Todd's paralysis is partly due to cortical ischaemia and arteriovenous shunts which develop through vasomotor or metabolic changes. Following that theory it would be likely that cerebrovascular diseases could cause a higher rate of Todd's paralysis. We found Todd's paralysis in only 6.3% of the patients. In a study by Hornig et al.,
      • Hornig C.R.
      • Buettner T.
      • Hufnagl A.
      • Schroeder-Rosenstock K.
      • Dorndorf W.
      Epileptic seizures following ischaemic cerebral infarction – clinical picture, CT findings and prognosis.
      a rate of 10% was described but only ischaemic strokes were included.
      In our study, 5.5% had early seizures and 6.2% had late seizures; 6.7% developed epilepsy. Late seizures were associated with epilepsy. This was described before by various authors.
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • Berges S.
      • Moulin T.
      • Berger E.
      • Tatu L.
      • Sablot D.
      • Challier B.
      • et al.
      Seizures and epilepsy following strokes: recurrence factors.
      • Misirli H.
      • Özge A.
      • Somay G.
      • Erdogan N.
      • Erkal H.
      • Erenoglu N.Y.
      Seizure development after stroke.
      • Benbir G.
      • Ince B.
      • Bozluolcay M.
      The epidemiology of post-stroke epilepsy according to stroke subtypes.
      • So E.L.
      • Annegers J.F.
      • Hauser W.A.
      • O’Brien P.C.
      • Whisnant J.P.
      Population-based study of seizure disorders after cerebral infarction.
      • Hornig C.R.
      • Buettner T.
      • Hufnagl A.
      • Schroeder-Rosenstock K.
      • Dorndorf W.
      Epileptic seizures following ischaemic cerebral infarction – clinical picture, CT findings and prognosis.
      • Cervoni L.
      • Artico M.
      • Salvati M.
      • Bristot R.
      • Franco C.
      • Delfini R.
      Epileptic seizures in intracerebral haemorrhage: a clinical and prognostic study of 55 cases.
      • Kotila M.
      • Waltimo O.
      Epilepsy after stroke.
      • Sitajayalakshmi S.
      • Mani J.
      • Borgohain R.
      • Mohandas S.
      Post stroke epilepsy.
      • Sung C.
      • Chu N.S.
      Epileptic seizures in thrombotic stroke.
      Even though there are many different criteria for early seizures ranging from 24 h after stroke onset
      • Burn J.
      • Dennis M.
      • Bamford J.
      • Sandercock P.
      • Wade D.
      • Warlow C.
      Epileptic seizures after a first stroke: the Oxfordshire community stroke project.
      up to 30 days,
      • Lancman M.E.
      • Golimstok A.
      • Norscini J.
      • Granillo R.
      Risk factors for developing seizures after a stroke.
      • De Reuck J.
      • Goethals M.
      • Vonck K.
      • Van Maele G.
      Clinical predictors of late-onset seizures and epilepsy in patients with cerebrovascular disease.
      results are similar.
      • Reith J.
      • Jorgensen H.S.
      • Nakayama H.
      • Raaschou H.O.
      • Olsen T.S.
      Seizures in acute stroke: predictors and prognostic significance.
      • Labovitz D.L.
      • Hauser A.W.
      • Sacco R.L.
      Prevalence and predictors of early seizure and status epilepticus after first stroke.
      • Cordonnier C.
      • Henon H.
      • Derambure P.
      • Pasquier F.
      • Leys D.
      Influence of pre-existing dementia on the risk of post-stroke epileptic seizures.
      This is due to the fact that most early seizures appear within the first 24 to 48 h after onset of stroke. In our study, 17 seizures (73.9% of all early seizures) developed within the first 24 h which is in accordance with recent data.
      • Mecarelli O.
      • Pro S.
      • Randi F.
      • Dispenza D.
      • Correnti A.
      • Pulitano P.
      • et al.
      EEG patterns and epileptic seizures in acute phase stroke.
      We found cortical involvement to be a significant risk factor for the development of late seizures confirming findings by DeReuck et al.,
      • De Reuck J.
      • Goethals M.
      • Vonck K.
      • Van Maele G.
      Clinical predictors of late-onset seizures and epilepsy in patients with cerebrovascular disease.
      while Shinton et al.
      • Shinton R.A.
      • Gill J.S.
      • Melnick S.C.
      • Gupta A.K.
      • Beevers D.G.
      The frequency, characteristics and prognosis of epileptic seizures at the onset of stroke.
      found no difference. In the Copenhagen Stroke Study,
      • Reith J.
      • Jorgensen H.S.
      • Nakayama H.
      • Raaschou H.O.
      • Olsen T.S.
      Seizures in acute stroke: predictors and prognostic significance.
      cortical involvement was not significantly associated with early seizures in multivariate analysis. Other authors
      • Bladin C.F.
      • Alexandrov A.V.
      • Bellavance A.
      • Bornstein N.
      • Chambers B.
      • Coté R.
      • et al.
      Seizures after stroke.
      • Arboix A.
      • Garcia-Eroles L.
      • Massons J.B.
      • Oliveres M.
      • Comes E.
      Predictive factors of early seizures after acute cerebrovascular disease.
      • Lamy C.
      • Domigo V.
      • Semah F.
      • Arquizan C.
      • Trystram D.
      • Coste J.
      • et al.
      Early and late seizures after cryptogenic ischemic stroke in young adults.
      • So E.L.
      • Annegers J.F.
      • Hauser W.A.
      • O’Brien P.C.
      • Whisnant J.P.
      Population-based study of seizure disorders after cerebral infarction.
      found that cortical involvement was associated with early seizures. Others noted that IVT and ICH resulted in a higher rate of epilepsy compared to ischaemic stroke.
      • Benbir G.
      • Ince B.
      • Bozluolcay M.
      The epidemiology of post-stroke epilepsy according to stroke subtypes.
      • Krakow K.
      • Sitzer M.
      • Rosenow F.
      • Steinmetz H.
      • Foerch C.
      for the Arbeitsgruppe Schlaganfall Hessen
      Predictors of acute poststroke seizures.
      While Kotila et al.
      • Kotila M.
      • Waltimo O.
      Epilepsy after stroke.
      stated that more female patients developed epilepsy, we found no significant difference.
      Although we subdivided the patients with seizures in patients with single seizures and epilepsy, these findings might not be representative because the minimum follow up period was 3 months. It is possible that we missed recurrent seizures among some patients. In a phone interview, it is also likely that some patients denied having had seizures due to social expectancy or improper comprehension. In addition, Blum et al.
      • Blum D.E.
      • Eskola J.
      • Fisher R.S.
      Patient awareness of seizures.
      noted that only 26% of the patients are always aware of their seizures. This, however, is a problem that is always faced when examining longtime outcome concerning seizure development.
      Our study has some limitations. First, most patients were enrolled retrospectively. This might cause a selection bias since patients with severe seizures could have passed away or were referred to nursing homes where they could not be contacted. Second, we lost 139 patients in the follow-up. The reasons for this loss remain unclear but it is likely that patients with severe impairment had to move to nursing homes or other places and could therefore not be contacted. This would mean a negative selection bias since patients with severe seizures were not detected. Third, we evaluated seizures and their semiology in the majority of patients by a telephone interview. This is of course not an appropriate method to detect all types of seizures. However, it is difficult to approach stroke patients with severe disability anyway, even if they are examined face to face. Furthermore, the telephone interview was performed by an experienced investigator and included also contact to the relatives of the patients in most cases. Therefore, we believe that our data are as correct as it is possible in this specific clinical situation.
      Based on our data, we conclude:
      • -
        Patients with IVT are significantly more at risk to develop a single seizure than patients with bleeding or ischaemic stroke but do not have a higher risk of developing epilepsy or status epilepticus.
      • -
        Bleeding leads to the development of epilepsy in 50% of the cases. This finding was not statistically significant but shows a tendency for a more severe course compared to the other aetiologies.
      • -
        In ischaemic stroke, macroangiopathy leads more often to seizures than cardioembolic strokes.
      • -
        A higher score of the NIH stroke scale predicts seizure development. This is more likely for late seizures than for early seizures, but it is not helpful in predicting the development of epilepsy.
      • -
        Younger patients are more at risk to develop single seizures and epilepsy than older patients but this finding failed to show statistical significance in multivariate analysis.
      • -
        Neither cortical involvement in ischaemic stroke nor the presence of multiple infarcts or their location regarding vascular territories and hemisphere are useful in predicting the development of seizures.
      • -
        We tested for common lifestyle, vascular, and metabolic risk factors of stroke and for dementia but could not observe any correlation between those and the development of seizures.
      • -
        The present analysis shows that only the type of stroke and stroke severity have a significant potential in predicting seizure development after a first ever stroke on a multivariate level. All other factors do not exceed the univariate level. In the setting of ischaemic strokes only the presence of macroangiopathic stroke has predictive value.
      Concerning these findings further research should clarify whether these factors are persistent if tested in different age groups. New diagnostic approaches such as diffusion and perfusion imaging for risk stratification of seizure development after stroke are needed as the pathomechanisms of stroke seem to be more important for the development of seizures than underlying conditions. Furthermore, clinical trials are warranted whether patients with a higher risk of developing epilepsy after stroke do benefit from early or pre-emptive prophylactic treatment.

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