Depression in epilepsy: etiology, phenomenology, and treatment

Quality of life and mood in patients with medically intractable epilepsy treated with targeted responsive neurostimulation

PURPOSE

The primary efficacy and safety measures from a trial of responsive neurostimulation for focal epilepsy were previously published. In this report, the findings from the same study are presented for quality of life, which was a supportive analysis, and for mood, which was assessed as a secondary safety endpoint.

METHODS

The study was a multicenter randomized controlled double-blinded trial of responsive neurostimulation in 191 patients with medically resistant focal epilepsy. During a 4-month postimplant blinded period, patients were randomized to receive responsive stimulation or sham stimulation, after which all patients received responsive neurostimulation in open label to complete 2years. Quality of life (QOL) and mood surveys were administered during the baseline period, at the end of the blinded period, and at year 1 and year 2 of the open label period.

RESULTS

The treatment and sham groups did not differ at baseline. Compared with baseline, QOL improved in both groups at the end of the blinded period and also at 1year and 2years, when all patients were treated. At 2years, 44% of patients reported meaningful improvements in QOL, and 16% reported declines. There were no overall adverse changes in mood or in suicidality across the study. Findings were not related to changes in seizures and antiepileptic drugs, and patients with mesial temporal seizure onsets and those with neocortical seizure onsets both experienced improvements in QOL.

CONCLUSIONS

Treatment with targeted responsive neurostimulation does not adversely affect QOL or mood and may be associated with improvements in QOL in patients, including those with seizures of either mesial temporal origin or neocortical origin.

Altered γ-aminobutyric acid neurotransmission in major depressive disorder: a critical review of the supporting evidence and the influence of serotonergic antidepressants

Evidence suggesting that central nervous system γ-aminobutyric acid (GABA) concentrations are reduced in patients with major depressive disorder (MDD) has been present since at least 1980, and this idea has recently gained support from more recent magnetic resonance spectroscopy data. These observations have led to the assumption that MDD’s underlying etiology is tied to an overall reduction in GABA-mediated inhibitory neurotransmission. In this paper, we review the mechanisms that govern GABA and glutamate concentrations in the brain, and provide a comprehensive and critical evaluation of the clinical data supporting reduced GABA neurotransmission in MDD. This review includes an evaluation of magnetic resonance spectroscopy data, as well as data on the expression and function of the GABA-synthesizing enzyme glutamic acid decarboxylase, GABA neuron-specific cell markers, such as parvalbumin, calretinin and calbindin, and the GABA_A and GABA_B receptors in clinical MDD populations. We explore a potential role for glial pathology in MDD-related reductions in GABA concentrations, and evidence of a connection between neurosteroids, GABA neurotransmission, and hormone-related mood disorders. Additionally, we investigate the effects of GABAergic pharmacological agents on mood, and demonstrate that these compounds have complex effects that do not universally support the idea that reduced GABA neurotransmission is at the root of MDD. Finally, we discuss the connections between serotonergic and GABAergic neurotransmission, and show that two serotonin-focused antidepressants – the selective serotonin-reuptake inhibitor fluoxetine and the multimodal antidepressant vortioxetine – modulate GABA neurotransmission in opposing ways, despite both being effective MDD treatments. Altogether, this review demonstrates that there are large gaps in our understanding of the relationship between GABA physiology and MDD, which must be remedied with more data from well-controlled empirical studies. In conclusion, this review suggests that the simplistic notion that MDD is caused by reduced GABA neurotransmission must be discarded in favor of a more nuanced and complex model of the role of inhibitory neurotransmission in MDD.

Antidepressants for people with epilepsy and depression

BACKGROUND

Depressive disorders are the most common psychiatric comorbidity in patients with epilepsy, affecting around one-third, with a significant negative impact on quality of life. There is concern that patients may not be receiving appropriate treatment for their depression because of uncertainty regarding which antidepressant or class works best and the perceived risk of exacerbating seizures. This review aims to address these issues and inform clinical practice and future research.

OBJECTIVES

We aimed to review and synthesise evidence from randomised controlled trials of antidepressants and prospective non-randomised studies of antidepressants used for treating depression in patients with epilepsy. The primary objectives were to evaluate the efficacy and safety of antidepressants in treating depressive symptoms and the effect on seizure recurrence.

SEARCH METHODS

We conducted a search of the following databases: the Cochrane Epilepsy Group Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL 2014, Issue 5), MEDLINE (Ovid), SCOPUS, PsycINFO, www.clinicaltrials.gov and conference proceedings, including studies published up to 31 May 2014. There were no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and prospective non-randomised cohort controlled and uncontrolled studies investigating children or adults with epilepsy treated with an antidepressant for depressive symptoms. The intervention group consisted of patients receiving an antidepressant drug in addition to an existing antiepileptic drug regimen. The control group(s) consisted of patients receiving a placebo, comparative antidepressant, psychotherapy or no treatment in addition to an existing antiepileptic drug regimen.

DATA COLLECTION AND ANALYSIS

We extracted data on trial design factors, patient demographics and outcomes for each study. The primary outcomes were changes in depression scores (proportion with a greater than 50% improvement or mean difference) and change in seizure frequency (mean difference or proportion with a seizure recurrence or episode of status epilepticus, or both). Secondary outcomes included the number of patients withdrawing from the study and reasons for withdrawal, as well as any adverse events. Two authors undertook data extraction separately for each included study. We then cross-checked the data extraction. We assessed risk of bias using a version of the extended Cochrane Collaboration tool for assessing risk of bias in both randomised and non-randomised studies. We presented binary outcomes as risk ratios (RRs) with 95% confidence intervals (CIs). We presented continuous outcomes as standardised mean differences (SMDs) with 95% CIs, and mean differences (MDs) with 95% CIs. If possible we intended to use meta-regression techniques to investigate possible sources of heterogeneity however this was not possible due to lack of data.

MAIN RESULTS

We included in the review eight studies (three RCTs and five prospective cohort studies) including 471 patients with epilepsy treated with an antidepressant. The RCTs were all single-centre studies comparing an antidepressant versus active control, placebo or no treatment. The five non-randomised prospective cohort studies reported on outcomes mainly in patients with partial epilepsy treated for depression with a selective serotonin reuptake inhibitor (SSRI). We rated all the RCTs and one prospective cohort study as having unclear risk of bias. We rated the four other prospective cohort studies as having high risk of bias. We were unable to perform any meta-analysis for the proportion with a greater than 50% improvement in depression scores because the studies reported on different treatment comparisons. The results are presented descriptively and show a varied responder rate of between 24% and 97%, depending on the antidepressant given. For the mean difference in depression score we were able to perform a limited meta-analysis of two prospective cohort studies of citalopram, including a total of 88 patients. This gave low quality evidence for the effect estimate of 1.17 (95% CI 0.96 to 1.38) in depression scores. Seizure frequency data were not reported in any RCTs and we were unable to perform any meta-analysis for prospective cohort studies due to the different treatment comparisons. The results are presented descriptively and show that treatment in three studies with a selective serotonin reuptake inhibitor did not significantly increase seizure frequency. Patients given an antidepressant were more likely to withdraw due to adverse events than inefficacy. Reported adverse events for SSRIs included nausea, dizziness, sedation, gastrointestinal disturbance and sexual dysfunction. Across three comparisons we rated the evidence as moderate quality due to the small sizes of the contributing studies and only one study each contributing to the comparisons. We rated the evidence for the final comparison as low quality as there was concern over the study methods in the two contributing studies.

AUTHORS' CONCLUSIONS

Existing evidence on the effectiveness of antidepressants in treating depressive symptoms associated with epilepsy is very limited. Only one small RCT demonstrated a statistically significant effect of venlafaxine on depressive symptoms. We have no high quality evidence to inform the choice of antidepressant drug or class of drug in treating depression in people with epilepsy. This review provides low quality evidence of safety in terms of seizure exacerbation with SSRIs, but there are no available comparative data on antidepressant classes and safety in relation to seizures. There are currently no comparative data on antidepressants and psychotherapy in treating depression in epilepsy, although psychotherapy could be considered in patients unwilling to take antidepressants or where there are unacceptable side effects. Further comparative clinical trials of antidepressants and psychotherapy in large cohorts of patients with epilepsy and depression are required to better inform treatment policy in the future.

The dilemma of treatments for epileptic patients with depression

Depression is a state of low mood and aversion to activity. It may occur due to existence of other mental or physical diseases or from the medications for those illnesses. It is one of the leading sources of disability. Among these physical diseases, epilepsy is widely recognized as one of the main causes of depression. Patients with epilepsy are at high risk of developing depressive symptoms, and the suicide rates in patients with epilepsy have been reported to be much higher than in the general population. However, due to fears of lowering seizure threshold and adverse drug interactions between antidepressants and antiepileptic drugs, physician are reluctant to place patients with epilepsy on antidepressant medication. As a result, the question has been raised that what the best managements should be used to treat epileptic patients with depression. In this review, the currently used medications for antidepressants and antiepileptic drugs were summarized by their working targets in order to establish appropriate pharmacological management of depression and epilepsy. Despite the complex relationship between epilepsy and depression, coadministration of antidepressants and AEDs can still be done safely and effectively under the conditions of good clinical management. The ideal antidepressants for people with epilepsy should be efficacious but with few adverse effects, which will not antagonize GABAergic mechanisms or interfere with plasma anticonvulsant concentrations.

Validation of the Greek version of the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E)

The Neurological Disorders Depression Inventory for Epilepsy (NDDI-E) was developed as a screening tool for symptoms of major depressive episodes in people with epilepsy. Our study describes the development, validation, and psychometric properties of the Greek version of the NDDI-E. A consecutive sample of 101 patients with epilepsy, eligible to participate in the study, has been assessed using the Mini International Neuropsychiatric Interview version 5.0.0 and the NDDI-E. All patients had no major difficulties in understanding or answering the questions of the Greek version. Cronbach's alpha coefficient was 0.74. Receiver operating characteristic analysis showed an area under the curve of 91% (95% CI=83%-99%; SE: 0.040, p<0.001). At a cutoff score of greater than 15, the NDDI-E showed a sensitivity of 91%, a specificity of 81%, and a negative predictive value of 97%.

Interictal dysphoric disorder: a frequent psychiatric comorbidity among patients with epilepsy who were followed in two tertiary centers

Psychiatric disorders are frequent among patients with epilepsy. Data in the literature have shown a heterogeneous clinical presentation of psychiatric disorders in patients with epilepsy. Interictal dysphoric disorder could be a specific psychiatric comorbidity associated with epilepsy, primarily in patients treated in tertiary centers. Objective The present study aimed to determine the prevalence of interictal dysphoric disorder among patients with epilepsy who were followed in two tertiary epilepsy services in Brazil. Method Sixty-five patients with epilepsy completed the Portuguese version of the Interictal Dysphoric Disorder Inventory. Results Thirty-three (50.7%) patients fulfilled the diagnostic criteria for interictal dysphoric disorder, although all participants answered positively to having at least one key symptom. Conclusion The high rate of patients with epilepsy who fulfilled the diagnosis of interictal dysphoric disorder confirms an association between epilepsy and psychiatric disorders. However, there is clearly a need to improve diagnostic tools to allow better differentiation between interictal dysphoric disorder and other psychiatric disorders.

Neurocognitive and psychological profiles of adult patients with epilepsy in Hong Kong

Cognitive deficits and psychological impairments are often associated with seizures. In order to describe the neuropsychological profiles of adult patients with epilepsy (PWEs) in Hong Kong China, a total of 186 PWEs were recruited with 102 being drug-responsive and 84 being drug-resistant. Symptoms of depression, anxiety, and epilepsy-specific quality of life (QOL) were measured. Cognitive assessments consisted of intelligence, memory, verbal and visual abilities, and executive function. Neurocognitive impairments were prevalent among PWEs, and patients with drug-resistant epilepsy had significantly more impaired psychological and cognitive profiles. Thirty-nine percent and 30% of patients with drug-resistant epilepsy reported moderate to severe levels of anxiety and depression, respectively, versus 16% and 7% of patients with drug-responsive epilepsy. The most commonly occurring cognitive deficit was memory. Thirty-five percent to 47% of patients with drug-resistant epilepsy and 26% to 35% of patients with drug-responsive epilepsy were compromised in verbal recall memory. Our findings also suggested significant correlations between psychological well-being and cognitive performance. Patients who reported more psychological symptoms tended to perform worse in neurocognitive tests. Identification and management of neuropsychological difficulties in PWEs are important and should be included in primary epilepsy care.

Psychiatric disorders in patients with psychogenic nonepileptic seizures and drug-resistant epilepsy: a study of an Argentine population

Epidemiological data show that up to 20-30% of patients with psychogenic nonepileptic seizures (PNESs), resembling drug-resistant epilepsy (DRE), are referred to tertiary epilepsy centers. Furthermore, both disorders present high psychiatric comorbidity, and video-EEG is the gold standard to make differential diagnoses. In this study, we described and compared the clinical presentation and the frequency of psychiatric disorders codified in DSM IV in two groups of patients, one with PNESs and the other with DRE, admitted in a tertiary care epilepsy center of Buenos Aires, Argentina. We included 35 patients with PNESs and 49 with DRE; all were admitted in the video-EEG unit in order to confirm an epilepsy diagnosis and determine surgical treatment possibilities. All patients underwent a neurological and psychiatric assessment, according to standardized protocol (SCID I and II; DSM IV criteria). Student's t test was performed to compare continuous variables and Chi square test to compare qualitative variables. In this study, 33 (67%) patients with DRE and 35 (100%) patients with PNESs met criteria for at least one disorder codified in Axis I of DSM IV (p=0.003). Differences in the frequency of psychiatric disorder presentation were found between groups. Anxiety disorders (16.32% vs 40%; p=0.015), trauma history (24.5% vs 48.57%; p=0.02), posttraumatic stress disorder (4.08% vs 22.85%; p=0.009), and personality cluster B disorders (18.37% vs 42.86%; p=0.02) were more frequent in the group with PNESs. Psychotic disorders were more frequent in the group with DRE (20.4% vs 2.85%; p=0.019). Depression was equally prevalent in both groups. Standardized psychiatric assessment provides information that could be used by the mental health professional who receives the referral in order to improve quality of care and smooth transitions to proper PNES treatment, which should include a multidisciplinary approach including neurology and psychiatry.

Association between leisure time, physical activity, and mood disorder levels in individuals with epilepsy

The aim of this study was to investigate the association between physical activity levels (occupational, sports, and leisure time activities), depression, anxiety, and epilepsy. The behavioral outcomes of individuals with epilepsy (E) were also compared with healthy control subjects (C). The sample included 31 individuals with epilepsy (12 with idiopathic generalized epilepsy and 19 with partial epilepsy) and 31 control subjects. Self-rating questionnaires were used to assess mood (State-Trait Anxiety Inventory and Beck Depression Inventory), anxiety, and depression as well as habitual physical activity. Patients with epilepsy were more severely impaired compared to control subjects in both mood questionnaires and presented higher levels of depression (35%), state anxiety (18%), and trait anxiety (12.6%) when compared to the C group. Although physical activity level did not differ significantly between groups, linear regression analyses showed that the physical activity leisure level predicted 31% of depression levels and 26% of anxiety levels in the E group. These data suggest that low levels of physical activity may be considered a risk factor for the development of depression and anxiety and can play an important role in the quality of life of individuals with epilepsy.

Treatments for patients with comorbid epilepsy and depression: a systematic literature review

Depression is recognized as a serious comorbidity of epilepsy, but treatment of depression and anxiety in people with epilepsy is challenging. The aim of this article was to review published controlled clinical treatment studies of depression and anxiety in patients with epilepsy. The PubMed, Cochrane and PsycINFO databases were searched for controlled clinical trials, or controlled psychosocial or behavioral trials published in English before June 2012. Search terms were: seizures, epilepsy, depression, psychotherapy, cognitive therapy/treatment, behavioral therapy/treatment and nonpharmacologic therapy/treatment, education and stress management. Seven studies were included in this review. Interventions included antidepressant medications, antiepileptic medications, and cognitive behavioral therapy. Despite the methodological limitations in the studies identified by this review, both medications and psychotherapy improved depression and anxiety in patients with epilepsy. However, further research is needed in the form of randomized controlled clinical trials to establish appropriate pharmacological and psychosocial co-management of depression and epilepsy.

Epilepsy and neuropsychological comorbidities

PURPOSE OF REVIEW

Epilepsy is a chronic disorder with several associated comorbidities requiring timely recognition and treatment. This article discusses aspects of cognitive impairment; psychiatric disorders including depression, anxiety, and psychosis; and health-related quality-of-life issues pertaining to patients with epilepsy.

RECENT FINDINGS

Cognitive problems in epilepsy may be present early in the disease course. Advances in imaging techniques are allowing correlation of structure and function as they relate to cognitive impairment in epilepsy. The relationship between epilepsy, depression, and anxiety is increasingly recognized, and these psychiatric comorbidities may affect suicide risk, patient-reported adverse antiepileptic drug effects, and quality of life. Psychiatric disorders are underrecognized and undertreated in patients with epilepsy.

SUMMARY

Physicians who treat patients with epilepsy should be aware of the major impact that cognitive impairment and psychiatric comorbidities have on these patients. Identifying and treating these comorbidities in epilepsy patients is just as important as seizure treatment.

Psychiatric disorders after epilepsy diagnosis: a population-based retrospective cohort study

BACKGROUND

Psychiatric manifestations after occurrence of epilepsy have often been noted. However, the association between newly diagnosed epilepsy and psychiatric disorders afterward is not completely understood. We conducted two longitudinal cohorts for patients with and without epilepsy to investigate the risk factors and hazard ratios of developing psychiatric disorders after patients were newly diagnosed with epilepsy.

METHODS

We identified 938 patients with a new diagnosis of epilepsy and 518,748 participants without epilepsy from the National Health Insurance Research Database in 2000-2002 and tracked them until 2008. We compared the incidence of developing psychiatric disorders between the two cohorts, evaluated risk factors and measured the associated hazard ratios (HRs) and 95% confidence intervals (CIs) of developing psychiatric disorders.

FINDINGS

The incidences of psychiatric disorders for people with and without epilepsy were 94.1 and 22.6 per 1000 person-years, respectively. After adjusting the covariates, the epilepsy cohort showed the highest risks in mental retardation (HR 31.5, 95% CI 18.9 to 52.4), bipolar disorder (HR 23.5, 95% CI 11.4 to 48.3) and alcohol or drug psychosis (HR 18.8, 95% CI 11.1 to 31.8) among psychiatric complications developed after newly diagnosed epilepsy. The risk increased with epileptic general seizure and frequency of outpatient visits for epilepsy, as well as with emergency room visits and hospitalizations for epilepsy, and with older age. Chronologically, the highest risk occurred in the first year after epilepsy diagnosis (HR 11.4, 95% CI 9.88 to 13.2).

CONCLUSION

Various psychiatric disorders were demonstrated after newly diagnosed epilepsy and closely related to general seizure and use of medical services for epilepsy. This shows a need for integrated psychiatric care for patients newly diagnosed with epilepsy, especially in the first year.

Psychiatric comorbidity in refractory focal epilepsy: a study of 490 patients

We studied the prevalence and associated factors of psychiatric comorbidities in 490 patients with refractory focal epilepsy. Of these, 198 (40.4%) patients had psychiatric comorbidity. An Axis I diagnosis was made in 154 patients (31.4%) and an Axis II diagnosis (personality disorder) in another 44 (8.97%) patients. After logistic regression, positive family history of psychiatric comorbidities (O.R.=1.98; 95% CI=1.10-3.58; p=0.023), the presence of Axis II psychiatric comorbidities (O.R.=3.25; 95% CI=1.70-6.22; p<0.0001), and the epileptogenic zone located in mesial temporal lobe structures (O.R.=1.94; 95% CI=1.25-3.03; p=0.003) remained associated with Axis I psychiatric comorbidities. We concluded that a combination of clinical variables and selected structural abnormalities of the central nervous system contributes to the development of psychiatric comorbidities in patients with focal epilepsy.

Psychosocial predictors of depression and anxiety in patients with epilepsy: a systematic review

BACKGROUND

People with epilepsy (PWE) have a high chance of experiencing depression and anxiety disorders over their lifetime. However, those most at risk are unknown. Psychosocial variables have been suggested as potentially important risk factors. A systematic review was conducted in order to critically assess available evidence regarding the psychosocial predictors of depression and anxiety in adults with epilepsy.

METHODS

Electronic databases searched were MEDLINE, PsycINFO and Web of Science. Studies were included if they assessed depressive or anxiety symptoms using a validated questionnaire, and controlled for the role of potentially important epilepsy factors. Eleven studies were identified and assessed for research standards using the Quality Index Scale (QIS).

RESULTS

Ten of the eleven studies found at least one significant predictor of depression and all six studies that assessed anxiety found one or more significant predictors.

LIMITATIONS

Overall QIS score was only 7.5 out of 15, indicating significant design limitations of many included studies. There was also large variability between studies in measures used to assess psychosocial variables.

CONCLUSION

Studies did not support the importance of attributional theory and stigma in the development of depression in epilepsy. There was inconsistent support for the role of illness representations but likely support for the role of stress and self-efficacy. Consistent support was found for the role of coping strategies and perceived social support. Given that psychosocial factors are potentially modifiable, a better understanding of their role in the development of depression in people with epilepsy is urgently needed to guide effective treatments.

Validation of the Italian version of the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E)

The Neurological Disorders Depression Inventory for Epilepsy (NDDI-E) was developed for the rapid detection of a major depressive episode in people with epilepsy. It has been proven to be a user-friendly screening instrument. This study describes the development, validation, and psychometric properties of the Italian version of the NDDI-E. A consecutive sample of 120 outpatients with epilepsy has been assessed using the M.I.N.I. Plus version 5.0.0 and the NDDI-E. All patients had no major difficulties in understanding or answering the questions of the Italian version. Cronbach's alpha coefficient was 0.851. Receiver operating characteristic analysis showed an area under the curve of 0.943 (CI95%=0.902-0.985; SE 0.021; p<0.001), a cut off score of 13, a sensitivity of 86.2%, a specificity of 89%, a positive predictive value of 71.4%, and a negative predictive value of 95.3%.

Depression symptoms as a function of duration of intractable or controlled epilepsy

We examined if depression symptoms in patients with intractable (IE) or controlled epilepsy (CE) differ and how long after onset of epilepsy these effects would be most pronounced. The NDDI-E was administered to all outpatients (n=358) seen in a comprehensive epilepsy program clinic over a two-year period. Patients who met inclusion criteria (n=223) completed a total of 431 NDDI-E surveys over this time. Patients with a diagnosis of IE (n=72) or CE (n=151) were compared as a function of time since their epilepsy onset, segmented into 10-year epochs. Depression symptoms were higher in patients with IE compared to CE at 10-<20 years and did not differ at other time points. This study reveals differences in depression symptoms as a function of duration of epilepsy. Attending to the dynamic nature of depression symptoms in different epochs of epilepsy may be an important treatment target in patients with epilepsy.

Synthesis and evaluation of substituted diphenyl-1,3,4-oxadiazole derivatives for central nervous system depressant activity

Background

Substituted 1,3,4-oxadiazoles are of considerable pharmaceutical interest. 2,5-Substituted diphenyl-1,3,4-oxadiazoles are associated with diverse biological activities by the virtue of -N = C-O- grouping. In the view of wide range of biological properties associated with 1,3,4-oxadiazole, we have synthesized substituted derivatives of 1,3,4-oxadiazole (XIII-XXII), a versatile hydrophobic molecule possessing preliminary CNS properties, with the hope to potentiate the biological activities with lesser or limited amount of toxicities.

Method

The synthesis was based on ester substitution of substituted benzohydrazide in presence of hydrazine hydrate followed by cyclization in presence of phosphorus oxychloride. All the synthesized compounds were evaluated for their potential CNS depressant activities. Statistical analysis of the anticonvulsant, antidepressant, and antianxiety activity of the synthesized compounds on animals was evaluated using one-way analysis of variance (ANOVA).

Results

Two compounds 5-(4-nitrophenyl)-2-(4-chlorophenyl)-1,3,4-oxadiazole (XIV) and 5-(4-nitrophenyl)-2-(4-nitrophenyl)-1,3,4-oxadiazole (XV) were found to be the most promising compounds of the series in antidepressant, anticonvulsant and antianxiety activity with no neurotoxicity when compared with standard.

Conclusions

Among the synthesized compounds, it was found that incorporation of electron withdrawing group at C2 and C5 position of the oxadiazole ring led to high degree of pharmacological activity. Thus compounds 5-(4-nitrophenyl)-2-(4-chlorophenyl)-1,3,4-oxadiazole (XIV) and 5-(4-nitrophenyl)-2-(4-nitrophenyl)-1,3,4-oxadiazole (XV) showed excellent CNS depressant activities. The result of the present investigation may encourage us to develop and/or improve similar other related compounds and it may be assumed that further modifications may produce compounds of better activity with lesser side effects.

Assessment of the convulsant liability of antidepressants using zebrafish and mouse seizure models

In the past, antidepressants have been thought to possess proconvulsant properties. This assumption remains controversial, however, because anticonvulsant effects have been attributed to certain antidepressants. To date, it remains unclear which antidepressants can be used for the treatment of patients with epilepsy with depression. The present study was designed to determine the anticonvulsant and/or proconvulsant effects of three antidepressants (citalopram, reboxetine, bupropion) against pilocarpine- and pentylenetetrazole-induced acute seizures in larval zebrafish and mice. In zebrafish, all antidepressants were anticonvulsant in the pentylenetetrazole model. In addition, citalopram was anticonvulsant in the zebrafish pilocarpine model, whereas reboxetine and bupropion were without significant effect. In mice all three antidepressants increased some thresholds for pentylenetetrazole-induced convulsive-like behaviors at varying doses, whereas thresholds for pilocarpine-induced convulsive-like behaviors were generally lowered, particularly at the highest doses tested. In general we conclude that the convulsant liability of antidepressants is model and concentration dependent.

What is the role of depressive symptoms among other predictors of quality of life in people with well-controlled epilepsy on monotherapy?

The quality of life (QOL) of individuals with well-controlled epilepsy (WCE) is often not considered. We therefore investigated predictors determining QOL in patients who had been seizure free at least 1 year on stable antiepileptic drug (AED) monotherapy. They were asked to complete self-report health questionnaires, including the Beck Depression Inventory (BDI), Adverse Event Profile (AEP), and Quality of Life in Epilepsy Inventory-31 (QOLIE-31). We looked for predictors of QOLIE-31 scores among the various demographic, socioeconomic, and clinical factors and BDI, and AEP scores. Depression symptoms were manifested by 18.7% of patients. People with depression symptoms were more likely to report adverse events than those without depression symptoms. The strongest predictor of QOL was BDI score, followed by AEP total score, years of education, and income. BDI score had 3.37 times the effect of AEP total score. In conclusion, QOL of patients with WCE is determined mainly by depressive symptoms.

Depression and anxiety in patients with epilepsy, with or without other chronic disorders

BACKGROUND

Most people with epilepsy lead a normal emotional and cognitive life, however neurobehavioral problems can be found in a large number of patients. This study evaluates the prevalence of depression and anxiety among patients with epilepsy and determines whether having other chronic somatic illnesses increases the prevalence.

METHODS

Adults with epilepsy were recruited in either the inpatient epilepsy monitoring unit or the Outpatient Epilepsy Clinic at Thomas Jefferson University in 2006. Patients anonymously filled out a questionnaire, included data about age, sex, education, having other chronic illnesses, and degree of seizure control. The Hospital Anxiety and Depression scale was used to define the presence or absence of anxiety and depression. 

RESULTS

Two hundreds patients participated, with a mean age of 40.3±16 years. Nineteen (9.5%) patients had depression and 49 (24.5%) had anxiety. Age, seizure control, and having other chronic illnesses did not have a significant relationship with either depression or anxiety. Gender was significantly related to anxiety, with females displaying greater frequency of anxiety than males. Depression was inversely related to education.

CONCLUSIONS

It is probable that people with higher education use more effective ways to psychologically and physically adapt to their illness.

Depression in epilepsy: why aren't we treating?

Depression is a common and largely untreated comorbidity in patients with epilepsy. Our aim was to examine physician attitudes that may contribute to this treatment gap. We surveyed primary care physicians, neurologists, and psychiatrists chosen from the Ohio State Medical Board registry on the topics of depression in epilepsy, seizures with antidepressant use, and comfort in treating depression in epilepsy. Our data identified fear of increased seizure frequency with antidepressant use as a significant barrier to treatment. There was a clear inverse relationship between the estimated risk of antidepressant-induced seizures and comfort treating depression in epilepsy (P = 0.02), with 52% of primary care physicians identifying this as a reason for not treating depression in this population. Further education of community physicians and neurologists regarding the importance of treating depression in patients with epilepsy and research into the use of antidepressants in this population are indicated.

Quality of life in childhood epilepsy with lateralized epileptogenic foci

BACKGROUND

Measuring quality of life (QOL) helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges.

METHODS

Thirty-one parents of children with epilepsy filled the Health-Related Quality of Life in Childhood Epilepsy Questionnaire (QOLCE). Fifteen children had foci in the left hemisphere and sixteen in the right, as verified with Electroencephalography (EEG) examinations.

RESULTS

We found a significant correlation between foci lateralization and reduced QOL (Spearman's rho = 0.361, p < 0.046). Children with right hemispheric foci exhibited lower overall QOL, particularly in five areas: anxiety, social-activities, stigma, general-health, and quality-of-life.

CONCLUSIONS

We demonstrated for the first time that in children left- and right-hemispheric foci were associated with discordant QOL scores. Unlike in adults, foci in the right hemisphere led to worse emotional and social functioning demonstrating that seizures impact the brain differentially during development.

Evaluation of depression risk in LGI1 mutation carriers

PURPOSE

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).

METHODS

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).

RESULTS

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.

DISCUSSION

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.

Electroconvulsive therapy for major depression in an elderly person with epilepsy

The case of a 72-year-old woman with a history of 40 years of epilepsy and medication-refractory severe depression is described. Despite the chronicity of the present depressive episode, mild MRI pathology and somatic complications, especially pneumonia and drug-induced hyponatraemia, we observed rapid and complete remission of depressive symptoms in the course of ECT. Neither cognitive impairment nor a perceptible influence on the neurological illness was seen, and no increase in seizure threshold has been observed during the course of 2 years maintenance ECT treatment. This article is offered in an attempt to enrich the clinical literature in this field and therefore encourage psychiatrists to consider ECT and MECT as a safe and efficacious option in epileptic patients with major depressive disorder.

Suicidality in people taking antiepileptic drugs: What is the evidence?

Suicide is an important cause of premature death. In the general population, most people who commit suicide have a psychiatric problem at the time. People with epilepsy are thought to be at increased risk from suicide and suicidality (suicidal ideation or behaviour). Standardized mortality ratios estimated for suicide in people with epilepsy are usually between 3 and 5. Risk factors for suicide in people with epilepsy have been suggested, including early age of onset of seizures, temporal lobe epilepsy, severe seizures and recent control of seizures. Psychiatric co-morbidity also seems to be an important factor in people with epilepsy who commit suicide. In recent years, suicidality has been recognized as a complication of several groups of drugs and, most recently, antiepileptic drugs (AEDs) have been implicated. The US FDA performed a meta-analysis of 199 placebo-controlled studies of 11 AEDs used for seizure control, psychiatric or 'other' indications. There were four completed suicides in those taking AEDs and none in those taking placebo. The odds ratio for suicidal behaviour or ideation was 1.8 (95% CI 1.24, 2.66), suggesting that people taking AEDs are more at risk than those taking placebo. The odds ratio was significantly raised for people taking AEDs for epilepsy, but not for the other indications. AEDs may affect mood by means of several mechanisms. In people with epilepsy, however, the concept of forced normalization (or alternative psychosis) may also play a part. In this situation, control of seizures (by AEDs or epilepsy surgery) may alternate with psychotic features or, less commonly, depression, although this is not fully understood. The risk of suicidal ideation and behaviour as adverse effects of AED treatment, although increased, seems low. As a result of the FDA's alert clinicians are supposed to inform patients and their families of this increased risk but it is important to place it in a proper perspective. Some people with epilepsy are more likely to develop psychiatric adverse effects with any AEDs, and these people should be followed closely whenever a new AED is introduced. Nonetheless, in people with epilepsy the risk of suicidality associated with AEDs needs to be balanced against the risk of not treating the seizures. In fact, the risk of stopping AEDs or refusing to start AEDs for the control of a seizure disorder may be significantly worse and may result in serious harm, including death of the patient.

Determination of prevalence of depression in an epilepsy clinic using a brief DSM-IV-based self-report questionnaire

Depression in epilepsy is common, underrecognized, and an indicator of quality of life. The Patient Health Questionnaire nine-item depression scale (PHQ-9) is a self-administered questionnaire based on Diagnostic and Statistical Manual, Fourth Edition (DSM-IV) criteria with high sensitivity and specificity for diagnosing depression. Using the PHQ-9, we determined that one-third of 263 patients seen in an epilepsy clinic had scores consistent with major depression. Seizure-free patients had lower depression scores than those with persistent seizures. Depression scores were not related to the number or type of antiepileptic drugs used. One-half of patients with scores consistent with major depression were not on antidepressant medication. The brevity of the PHQ-9 is conducive to routine screening of patients with epilepsy.

Identifying depression in epilepsy in a busy clinical setting is enhanced with systematic screening

PURPOSE

Depression is a highly prevalent, relatively underdiagnosed and undertreated comorbid condition in epilepsy. The purpose of this study was to determine the effect of using a validated self-reporting depression scale on the ability to detect depression in people with epilepsy receiving care in a busy clinical setting.

METHODS

The Neurological Disorders Depression Inventory for Epilepsy (NDDI-E) is a 6-item questionnaire validated to screen for depression in people with epilepsy. We performed a retrospective chart review of 192 consecutive patients who had completed the NDDI-E while receiving care at a seizure clinic in the largest public hospital in Houston, Texas. For comparison, charts of 192 consecutive patients receiving care immediately prior to the implementation of the NDDI-E in the same clinic were assessed.

RESULTS

Fifty-five (28.6%) of patients screened positive for depression with the NDDI-E. They subsequently received a semi-structured psychiatric interview based on the DSM-IV model and 89% (n=49) were confirmed to have major depression. Use of the NDDI-E thus resulted in the detection of active depression in 25.5% (n=49) of the patients, whereas only 2.6% (n=5) of patients in the group not systematically screened were found to have active depression (p<0.0001). Thirty-two of the 49 (65%) patients with depression detected by screening were not previously diagnosed or treated. Multivariate analysis revealed that a history of depression, seizure frequency, and topiramate use were independent predictors of depression. Lamotrigine use was protective against depression.

DISCUSSION

Use of the NDDI-E significantly improved the ability to detect depression in epilepsy patients in a busy clinical practice.

Antiepileptic drugs and psychopathology of epilepsy: an update

Anti-epileptic drugs (AEDs) continue to be the mainstay of epilepsy treatment, but the benefits of seizure control need to be weighed carefully against possible adverse effects, which can include behavioral problems and psychiatric disorders. In this paper, the associations between AEDs and psychosis, depression and behavioral changes are reviewed. The concept of forced normalization and its clinical counterpart, alternative psychosis, are also discussed. Depression seems to be linked with AEDs potentiating GABAergic neurotransmission in patients with limbic system abnormalities such as hippocampal sclerosis. Psychoses have been described as associated with several of the new AEDs, and they are often seen in a setting in which previously refractory patients suddenly become seizure-free. In general terms, the use of AEDs in monotherapy, adopting slow titration schedules and low doses when possible, can significantly reduce the occurrence of behavioral adverse effects. A previous history of psychiatric disorder or a familial predisposition are important risk factors and should be always considered when choosing the appropriate AED.

Don't be afraid to treat depression in patients with epilepsy!

Major depression and related depressive disorders are highly prevalent in the general population and even more so in patients with epilepsy. Yet depression in these patients remains underdiagnosed and undertreated. This is particularly worrisome as depression has greater negative impact on quality of life than seizure frequency. Additionally, depression is associated with poorer seizure control, and the risk of suicide in patients with epilepsy is greatly increased. Reluctance to treat depression results from the traditional belief that antidepressants should be restricted in epilepsy because of a supposed decrease in seizure threshold. However, there is growing evidence that many antidepressants rather have anticonvulsant effects. Experimental studies show that in critical brain regions such as the frontal lobes and the limbic system enforced serotonergic circuits increase seizure threshold. Clinical data suggest that modern antidepressants may reduce seizure frequency in patients with pharmacoresistant epilepsy. Here we review the concept that selective reuptake inhibitors of serotonin (SSRIs) have a positive effect on the mood disorder as well as on epilepsy. When adhering to the usual precautions, treatment with SSRIs in patients with epilepsy and depression is safe and should not be withheld.

Temporal lobe epilepsy, depression, and hippocampal volume

OBJECTIVE

To evaluate the relationship between hippocampal volume loss, depression, and epilepsy.

BACKGROUND

There is a significantly increased incidence of depression and suicide in patients with epilepsy. Both epilepsy and depression are associated with reduced hippocampal volumes, but it is uncertain whether patients with both conditions have greater atrophy than those with epilepsy alone. Previous studies used depression measures strongly weighted to current state, and did not necessarily assess the influence of chronic major depressive disorder ("trait"), which could have a greater impact on hippocampal volume.

METHODS

Fifty-five epilepsy patients with complex partial seizures (CPS) confirmed by electroencephalography (EEG) had three-dimensional (3D)-spoiled gradient recall (SPGR) acquisition magnetic resonance imaging (MRI) scans for hippocampal volumetric analysis. Depression screening was performed with the Beck Depression Inventory (BDI, 51 patients) and with the structured clinical inventory for DSM-IV (SCID, 34 patients). For the BDI, a score above 10 was considered mild to moderate, above 20 moderate to severe, and above 30 severe depression. MRI and clinical analysis were performed blinded to other data. Statistical analysis was performed with Systat using Student's t test and analysis of variance (ANOVA).

RESULTS

There was a significant interaction between depression detected on SCID, side of focus, and left hippocampal volume. Patients with a diagnosis of depression and a right temporal seizure focus had significantly lower left hippocampal volume. A similar trend for an effect of depression on right hippocampal volume in patients with a right temporal focus did not reach statistical significance.

CONCLUSIONS

Our results suggest that patients with right temporal lobe epilepsy and depression have hippocampal atrophy that cannot be explained by epilepsy alone.

Self-proxy agreement and correlates of health-related quality of life in young adults with epilepsy and mild intellectual disabilities

This study investigated health-related quality of life (HRQOL) in young adults with epilepsy and intellectual disabilities. First, agreement between self-reports and proxy reports of HRQOL was examined. Second, medical and psychological contributions to HRQOL were explored. Thirty-six patients were interviewed using the Quality of Life in Epilepsy inventory (QOLIE-31), the Hospital Anxiety and Depression Scale, and the Neuroticism and Extraversion scales of the NEO Five-Factor Inventory. Medical data were taken from files. Professional caregivers completed rephrased QOLIE-31-questionnaires. The perspectives on HRQOL differed systematically: Caregivers underrated their clients' HRQOL on average. Few correlations with medical characteristics emerged, whereas all psychological variables were strongly related to HRQOL. Neuroticism, Age at Disability Onset, and their interaction explained 71% of the HRQOL variance. Results indicate that proxy reports do not provide valid substitutes for most of the self-reported HRQOL subscales. Psychological treatment of negative affectivity and after critical life events in adolescence may improve HRQOL in young adults with epilepsy and mild intellectual disabilities.

Prevalence, patterns, service needs, and assessment of neuropsychiatric disorders among people with epilepsy in residential care: validation of the Neuropsychiatric Inventory as a caregiver-rated measure of neuropsychiatric functioning in epilepsy

We assessed 228 people with epilepsy (PWE) in the residential care setting using the Neuropsychiatric Inventory (NPI) and Brief Psychiatric Rating Scale (BPRS) as caregiver- and observer-rated instruments. There was a significant burden of psychopathology, about half of all subjects surveyed scoring positive on either or both instruments. Psychopathology as measured by the NPI and BPRS was significantly greater in cognitively impaired subjects than in those with intact cognitive function. The NPI was found to be a valid caregiver-rated measure of psychopathology in PWE, with a principal components analysis yielding a reliable and interpretable four-factor solution, psychosis, interictal dysphoric disorder, depression, and anxiety being identified. Mental health service needs were found to be considerable in this population, with a significant hidden burden of psychiatric comorbidity. As this population has ongoing service needs through the life span, further research is necessary.

Relationship between post-operative depression/anxiety and hippocampal/amygdala volumes in temporal lobectomy for epilepsy

PURPOSE

Patients with temporal lobe epilepsy (TLE) often present mood disturbances, which may either exacerbate or remit following surgery. The objective of the study was to investigate the relationship between post-operative depressive/anxiety symptoms and hippocampal/amygdala volumes following anterior temporal lobectomy.

METHODS

Thirty-five patients operated for TLE were assessed for mood disturbances by the Beck depression inventory (BDI) and Beck anxiety inventory (BAI). Post-operative MRI data were collected and volumetric analysis of the hippocampi (HV) and amygdala (AV) was performed. Correlations between volumetric data, measures of mood, and demographic and clinical data were calculated.

RESULTS

BDI scores significantly correlated with the intact HV (p=0.029) as well as the absolute difference between the intact and remnant HV (p=0.021). This was evident in left-side resections (p=0.049); in right-side resections the correlation was marginally non- significant (p=0.057). Depressed patients also had smaller remnant AV (p=0.002). Furthermore, BAI was negatively correlated with the HV remnant in left-side resections (p=0.038). No other significant associations between post-operative mood disturbances and various demographic and clinical variables were observed.

CONCLUSION

The severity of depressive symptomatology in operated epilepsy patients correlates with the extent of hippocampal and amygdala resection; this association appears to be more evident in left-side resections.

Epilepsy and suicide: pathogenesis, risk factors, and prevention

Depression and suicide tendencies are common in chronic diseases, especially in epilepsy and diabetes. Suicide is one of the most important causes of death, and is usually underestimated. We have analyzed several studies that compare mortality as a result of suicide in epileptic patients and in the general population. All the studies show that epileptic patients have a stronger tendency toward suicide than healthy controls. Moreover it seems that some kinds of epilepsy have a higher risk for suicide (temporal-lobe epilepsy). Among the risk factors are surgery therapy (suicide tendency five times higher than patients in pharmacological therapy), absence of seizures for a long time, especially after being very frequent, and psychiatric comorbidity (major depression, anxiety-depression disorders, personality disorders, substance abuse, psychoses). The aim of the review was to analyze the relationship between suicide and epilepsy, to identify the major risk factors, and to analyze effective treatment options.

Psychiatric and psychosocial consequences of pediatric epilepsy

Psychiatric and psychosocial complications with pediatric epilepsy are more common than with other chronic medical illnesses. Epilepsy is a disorder of hyperexcitable neurons and may have direct neurophysiologic effects leading to psychiatric comorbidity. Epilepsy also requires significant lifestyle adjustment, and the psychosocial impact on children and their families may be severe. The scientific literature is underrepresented in terms of diagnosis and management of psychiatric and psychosocial comorbidity associated with pediatric epilepsy. However, recent scientific efforts have assisted in highlighting the impact of these comorbidities and in bringing them to greater clinical attention. This review incorporates the available evidence with an aim to describe effective strategies for diagnosis and management.