Introduction: Poststroke epilepsy (PSE) is the most common form of acquired epilepsy after middle age. The primary aim of this study was to study the impact of PSE on prognosis. A secondary aim was to validate recent findings from smaller studies on the risk of developing PSE on a nationwide scale. Patients and methods: We performed a nationwide cohort study based on comprehensive national registries and included patients without a prior epilepsy diagnosis surviving more than 2 months after stroke, identified by the Swedish Stroke Register (Riksstroke) and linked to the National Patient Register and Cause of Death Register. Cox proportional time-updated hazard model was used to assess the risk of death, with or without multivariable adjustment for possible confounders, and multiple Cox regression was used to examine associations between PSE and clinical characteristics. Results: In 106,455 patients, PSE (defined as a seizure diagnosis more than 7 days after stroke) was detected in 7.3%, with lower cumulative incidence after ischemic stroke (6.4%) than after intracerebral haemorrhage (12.4%). Stroke severity, intracerebral haemorrhage and young age were associated with a risk of PSE. The risk of death was increased in patients with PSE (hazard ratio: 1.68, 95% confidence interval: 1.25–1.53). Also with adjustments for age, comorbidities and stroke severity, an increased risk of death associated with PSE remained. Discussion: Studies are needed on potential causes of increased mortality in PSE, such as a direct seizure-related mortality, less ambitious secondary stroke prophylaxis or rehabilitation, or impact of antiepileptic drugs on cardiovascular risk.

Stroke is among the most common causes of epilepsy after middle age. Patients with poststroke epilepsy (PSE) differ in several respects from patients with other forms of structural–metabolic epilepsy; not least in age, age-related sensitivity to side effects of antiepileptic drugs (AEDs), and specific drug–drug interaction issues related to secondary-stroke prophylaxis. Encouragingly, there has lately been remarkable activity in the study of PSE. Three developments in PSE research deserve particular focus. First, large prospective trials have established the incidence and risk factors of PSE in the setting of modern stroke care. Stroke severity, cortical location, young age, and haemorrhage remain the most important risk factors. Second, although more studies are needed, epidemiological data indicate that the risk of PSE may be influenced, for instance, by statin treatment. Third, studies are emerging regarding the treatment and prognosis of PSE. Levetiracetam and lamotrigine may be well tolerated treatment options and seizure freedom is achieved in at least a similar proportion of patients as in other epilepsies. Furthermore, new animal models such as photothrombotic stroke gives hope of a more clear understanding of PSE epileptogenesis in the near future. In summary, PSE shows indications of maturing into an independent epilepsy research field. This review summarizes recent advances in our understanding of PSE and provides an update on management issues such as diagnosis, AED selection, and prognosis. Finally, future research challenges in the field are outlined.

To determine the cumulative incidence of epilepsy in a population-based cohort of patients with multiple sclerosis (MS) and to investigate the association between epilepsy and clinical features of MS. All available patients in the Swedish MS register (n = 14,545) and 3 age- and sex-matched controls per patient randomly selected from the population register (n = 43,635) were included. Data on clinical features of MS were retrieved from the Swedish MS register, and data on epilepsy and death were retrieved from comprehensive patient registers. The cumulative incidence of epilepsy was 3.5% (95% confidence interval [CI] 3.17-3.76) in patients with MS and 1.4% (95% CI 1.30-1.52) in controls (risk ratio 2.5, 95% CI 2.19-2.76). In a Cox proportional model, MS increased the risk of epilepsy (hazard ratio 3.2, 95% CI 2.64-3.94). Patients with relapsing-remitting MS had a cumulative incidence of epilepsy of 2.2% (95% CI 1.88-2.50), whereas patients with progressive disease had a cumulative incidence of 5.5% (95% CI 4.89-6.09). The cumulative incidence rose continuously with increasing disease duration to 5.9% (95% CI 4.90-7.20) in patients with disease duration ≥34 years. Patients with an Expanded Disability Status Scale (EDSS) score ≥7 had a cumulative incidence of epilepsy of 5.3% (95% CI 3.95-7.00). Disease duration and EDSS score were associated with epilepsy after multiple logistic regression (odds ratio [OR] 1.03, 95% CI 1.01-1.04 per year, p = 0.001; and OR 1.2, 95% CI 1.09-1.26 per EDSS step, p < 0.0001). Epilepsy is more common among patients with MS than in the general population, and a diagnosis of MS increases the risk of epilepsy. Our data suggest a direct link between severity of MS and epilepsy.

Robust and accessible biomarkers are greatly needed in epilepsy. Diagnostic and prognostic precision in the clinic needs to improve, and there is a need for objective quantification of seizure burden. In recent years, there have been advances in the development of accessible and cost‐effective blood‐based biomarkers in neurology, and these are increasingly studied in epilepsy. However, the field is in its infancy and specificity and sensitivity for most biomarkers in most clinical situations are not known. This review describes advancements regarding human blood biomarkers in epilepsy. Examples of biochemical markers that have been shown to have higher blood concentrations in study subjects with epilepsy include brain proteins like S100B or neuronal specific enolase, and neuroinflammatory proteins like interleukins, and tumor necrosis factor‐alpha. Some of the blood biomarkers also seem to reflect seizure duration or frequency, and levels decrease in response to treatment with antiseizure medication. For most biomarkers, the literature contains seemingly conflicting results. This is to be expected in an emerging field and could reflect different study populations, sampling or analysis techniques, and epilepsy classification. More studies are needed with emphasis put on the classification of epilepsy and seizure types. More standardized reporting could perhaps decrease result heterogeneity and increase the potential for data sharing and subgroup analyses.

Objective Traumatic brain injury (TBI) is a leading cause of epilepsy. Our aim was to characterise the risk of epilepsy in adults after hospitalisation for TBI. Methods Register-based cohort study. All individuals aged 18–100 with a first hospitalisation for TBI in the comprehensive national patient register in Sweden between 2000 and 2010 (n=111 947) and three controls per exposed (n=325 881), matched on age and sex were included. Exposed individuals were categorised according to TBI severity. Kaplan-Meier curves were used to estimate the risk of epilepsy and Cox regression to estimate the hazard in univariate or multivariate regression. Results The 10-year risk of epilepsy was 12.9% (95% CI 11.7% to 14.1%) for focal cerebral injuries, 8.1% (95% CI 7.5% to 8.7%) for diffuse cerebral injuries, 7.3% (95% CI 6.9% to 7.7%) for extracerebral injuries, 2.8% (95% CI 2.4% to 3.2%) for skull fractures and 2.6% (95% CI 2.4% to 2.8%) for mild TBI. The risk of epilepsy after any TBI was 4.0% (95% CI 3.8% to 4.2%). The corresponding 10-year risk for controls was 0.9% (95% CI 0.9% to 0.9%). The HR increased with a more severe injury, from 3.0 (95% CI 2.8 to 3.2) for mild injury to 16.0 (95% CI 14.5 to 17.5) for focal cerebral injury. Multivariable analyses identified central nervous system (CNS) comorbidities as risk factors, but TBI remained significant also after adjustment for these. Other identified risk factors were male sex, age, mechanical ventilation and seizure during index hospitalisation. Conclusion The risk of post-traumatic epilepsy is considerable, also with adjustments for CNS comorbidities.

The pharmacological treatment of epilepsy entails several critical decisions that need to be based on an individual careful risk–benefit analysis. These include when to initiate treatment and with which antiseizure medication (ASM). With more than 25 ASMs on the market, physicians have opportunities to tailor the treatment to individual patients´ needs. ASM selection is primarily based on the patient's type of epilepsy and spectrum of ASM efficacy, but several other factors must be considered. These include age, sex, comorbidities, and concomitant medications to mention the most important. Individual susceptibility to adverse drug effects, ease of use, costs, and personal preferences should also be taken into account. Once an ASM has been selected, the next step is to decide on an individual target maintenance dose and a titration scheme to reach this dose. When the clinical circumstances permit, a slow titration is generally preferred since it is associated with improved tolerability. The maintenance dose is adjusted based on the clinical response aiming at the lowest effective dose. Therapeutic drug monitoring can be of value in efforts to establish the optimal dose. If the first monotherapy fails to control seizures without significant adverse effects, the next step will be to gradually switch to an alternative monotherapy, or sometimes to add another ASM. If an add‐on is considered, combining ASMs with different modes of action is usually recommended. Misdiagnosis of epilepsy, non‐adherence and suboptimal dosing are frequent causes of treatment failure and should be excluded before a patient is regarded as drug‐resistant. Other treatment modalities, including epilepsy surgery, neuromodulation, and dietary therapies, should be considered for truly drug‐resistant patients. After some years of seizure freedom, the question of ASM withdrawal often arises. Although successful in many, withdrawal is also associated with risks and the decision needs to be based on careful risk–benefit analysis.