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Objective: We sought to determine which combination of clinical and electroencephalography (EEG) characteristics differentiate between an antiseizure medication (ASM)–resistant vs ASM‐responsive outcome for patients with idiopathic generalized epilepsy (IGE). Methods: This was a case‐control study of ASM‐resistant cases and ASM‐responsive controls with IGE treated at five epilepsy centers in the United States and Australia between 2002 and 2018. We recorded clinical characteristics and findings from the first available EEG study for each patient. We then compared characteristics of cases vs controls using multivariable logistic regression to develop a predictive model of ASM‐resistant IGE. Results: We identified 118 ASM‐resistant cases and 114 ASM‐responsive controls with IGE. First, we confirmed our recent finding that catamenial epilepsy is associated with ASM‐resistant IGE (odds ratio [OR] 3.53, 95% confidence interval [CI] 1.32–10.41, for all study subjects) after covariate adjustment. Other independent factors seen with ASM resistance include certain seizure‐type combinations (absence, myoclonic, and generalized tonic‐clonic seizures [OR 7.06, 95% CI 2.55–20.96]; absence and generalized tonic‐clonic seizures [OR 4.45, 95% CI 1.84–11.34]), as well as EEG markers of increased generalized spike‐wave discharges (GSWs) in sleep (OR 3.43, 95% CI 1.12–11.36 for frequent and OR 7.21, 95% CI 1.50–54.07 for abundant discharges in sleep) and the presence of generalized polyspike trains (GPTs; OR 5.49, 95% CI 1.27–38.69). The discriminative ability of our final multivariable model, as measured by area under the receiver‐operating characteristic curve, was 0.80. Significance: Multiple clinical and EEG characteristics independently predict ASM resistance in IGE. To improve understanding of a patient's prognosis, clinicians could consider asking about specific seizure‐type combinations and track whether they experience catamenial epilepsy. Obtaining prolonged EEG studies to record the burden of GSWs in sleep and assessing for the presence of GPTs may provide additional predictive value. [ABSTRACT FROM AUTHOR]

Summary: Objective: Mood disorders are the most common comorbid conditions in epilepsy, but the cause remains unclear. One possible explanation is a shared genetic susceptibility to epilepsy and mood disorders. We tested this hypothesis by evaluating lifetime prevalence of mood disorders in relatives with and without epilepsy in families containing multiple individuals with epilepsy, and comparing the findings with rates from a general population sample. Methods: The Composite International Diagnostic Interview was administered to 192 individuals from 60 families, including 110 participants with epilepsy of unknown cause (50 focal epilepsy [FE], 42 generalized epilepsy [GE], 6 FE and GE, 12 unclassifiable) and 82 relatives without epilepsy (RWOE). Odds ratios (ORs) for lifetime prevalence of mood disorders in participants with versus without epilepsy were computed through logistic regression, using generalized estimation equations to account for familial clustering. Standardized prevalence ratios (SPRs) were used to compare prevalence in family members with general population rates. Results: Compared with RWOE, ORs for mood disorders were significantly increased in participants with FE (OR = 2.4, 95% confidence interval [CI] = 1.1‐5.2) but not in those with GE (OR = 1.0, 95% CI = 0.4‐2.2). In addition, prevalence of mood disorders was increased in individuals with epilepsy who had ≥1 relative with FE. Compared with general population rates, mood disorders were significantly increased in individuals with FE but not in those with GE. Rates were also increased in RWOE, but not significantly so (SPR = 1.4, P = .14). Significance: These findings are consistent with the hypothesis of shared genetic susceptibility to epilepsy and mood disorders, but suggest (1) the effect may be restricted to FE, and (2) the shared genetic effect on risk of mood disorders and epilepsy may be restricted to individuals with epilepsy, that is, to those in whom the genetic risk for epilepsy is “penetrant.” [ABSTRACT FROM AUTHOR]

Objective: To examine the seizure trajectories of adults with epilepsy developing drug-resistant epilepsy (DRE) and to identify the predictors of seizure trajectory outcome. Methods: Adult patients failing two antiepileptic drugs (AEDs) due to inefficacy and starting their third AED at a tertiary epilepsy center were followed for seizure trajectory outcome during medical management. Seizure trajectories were categorized into one of four patterns: (1) course with constant seizures; (2) fluctuating course; (3) delayed attainment of seizure freedom (seizure freedom delayed for >12 months after start of the study, but patient stayed in seizure freedom); and (4) early attainment of seizure freedom (within 12 months of starting study). Multiple ordinal logistic regression models were used to estimate the association between trajectory categories and clinical factors. Results: Four hundred three adult patients met the eligibility criteria. Of these, 212 (53%) never achieved a seizure-free period of a year or more. The trajectories of 63 patients (16%) had a complex fluctuating trajectory, 62 (15%) had delayed onset of seizure freedom, and 66 (16%) had an early seizure freedom. Independent predictors associated with more favorable outcome trajectories were epilepsy type and length of follow-up. Specifically, compared to patients with focal epilepsy of temporal lobe, patients with focal epilepsy of occipital lobe (OR 3.80, 95% confidence interval [CI] 1.00-14.51, p = 0.04), generalized genetic (OR 3.23, 95% CI 1.88-5.57, p < 0.0001), unclear epilepsy type (OR 3.82, 95% CI 1.53-9.52, p < 0.005), and both focal and generalized epilepsy(OR 11.73, 95% CI 1.69-81.34, p = 0.01) were significantly more likely to experience a better trajectory pattern. Significance: Examination of patterns of seizure trajectory of patients with incident DRE showed that 31% were in continuous seizure freedom at the end of the observation period. [ABSTRACT FROM AUTHOR]

Depression is the most common comorbid condition in epilepsy. The cause of this comorbidity is unknown, and could involve psychosocial consequences of epilepsy, treatment side effects, seizure manifestations, or common neurobiologic mechanisms. One hypothesis of particular interest is a shared genetic susceptibility to epilepsy and depression. We tested this hypothesis by studying depressive symptoms in families with an identified genetic form of epilepsy: autosomal dominant partial epilepsy with auditory features caused by mutations in the leucine-rich, glioma inactivated 1 gene ( LGI1). A standardized depression screen was administered to 94 individuals from 11 families with mutations in LGI1, including 38 mutation carriers with epilepsy (AC), 11 clinically unaffected mutation carriers (UC), and 45 noncarriers (NC). Current depressive symptom scores were significantly higher in AC than in NC, an association that remained after excluding depressive symptoms that appeared likely to be caused by antiepileptic medication use. However, scores did not differ between UC and NC. Although LGI1 mutation carriers who were clinically affected with epilepsy had increased depressive symptoms, mutation carriers without epilepsy did not. These findings suggest that the increase in depressive symptoms in affected individuals from these families is related to epilepsy or its treatment rather than to LGI1 mutations per se. [ABSTRACT FROM AUTHOR]

To investigate the cumulative probabilities of ≥12 month seizure remission and seizure relapse following remission, and to test the associations of clinical characteristics with these two study end points in a prevalence cohort of intractable adult epilepsy patients during medical management. A retrospective cohort study of intractable epilepsy patients seen in 2001 at a single center was conducted. Kaplan–Meier analysis was used to estimate the cumulative probabilities of seizure remission and subsequent seizure relapse. Cox proportional hazards models were used to estimate the association (1) between clinical factors and ≥12 month seizure remission and (2) between clinical factors and seizure relapse following remission. One hundred eighty-seven subjects met the eligibility criteria for intractable epilepsy. The estimate of probability of remission was about 4% per year. Seizure remission was temporary for some individuals, as 5 out of 20 subjects with remission ultimately relapsed. No clinical factors predicted the likelihood of achieving ≥12 month seizure remission or subsequent seizure relapse. Some people with intractable epilepsy achieve ≥12 month seizure remission during medical treatment. Remission, however, is only temporary for some individuals. We were unable to identify clear predictors for remission. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Drug-resistant epilepsy in adults: Outcome trajectories after failure of two medications" is presented.