Is major depressive disorder specifically associated with mesial temporal sclerosis?

Distinctive electro-clinical, neuroimaging and histopathological features of temporal encephaloceles associated to epilepsy

OBJECTIVE

Encephaloceles (ENCs) may cause clinical complications, including drug-resistant epilepsy that can be cured with epilepsy surgery.

METHODS

We describe clinical, diagnostic, and neuropathological findings of 12 patients with temporal ENC and epilepsy evaluated for surgery and compare them with a control group of 26 temporal lobe epilepsy (TLE) patients.

RESULTS

Six patients had unilateral and 6 bilateral temporal ENCs. Compared to TLEs, ENCs showed i) later epilepsy onset, ii) higher prevalence of psychiatric comorbidities, iii) no history of febrile convulsions, and iv) ictal semiology differences. Seven patients had MRI signs of gliosis, and 9 of intracranial hypertension. Interictal EEG analysis in ENCs demonstrated significant differences with controls: prominent activity in the beta/gamma frequency bands in frontal regions, interictal short sequences of low-voltage fast activity, and less frequent and more localized interictal epileptiform discharges. Ictal EEG patterns analyzed in 9 ENCs showed delayed and slower contralateral spread compared to TLEs. All ENCs that underwent surgery (7 lobectomies and 1 lesionectomy) are in Engel class I. Neuropathological examination revealed 4 patterns: herniated brain fragments, focal layer I distortion, white matter septa extending into the cortex, and altered gyral profile.

CONCLUSIONS AND SIGNIFICANCE

The described peculiarities might help clinicians to suspect the presence of largely underdiagnosed ENCs.

Is depression in patients with temporal lobe epilepsy related to hippocampal sclerosis? A meta-analysis

OBJECTIVE

To systematically evaluate the association between hippocampal sclerosis (HS) and depression in patients with temporal lobe epilepsy (TLE) through a meta-analysis.

METHODS

Chinese and English databases, such as the China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals (VIP), WanFang, the Chinese Biomedical Literature Service System (SinoMed), PubMed and the Web of Science, were searched.

RESULTS

Two evaluators independently screened the literature, extracted data and evaluated the risk of bias in the included studies in accordance with the inclusion and exclusion criteria. RevMan 5.1 was used to analyze the data. A total of 786 patients with epilepsy were included in the study, including 82 depressive patients with HS and 64 depressive patients without HS. The results showed that the TLE patients with HS were more likely to develop depression than those without HS (odds ratio (OR)= 2.14, 95% confidence interval (CI) [1.45, 3.16], Z = 3.85, p = 0.0001).

CONCLUSION

HS can be considered a high-risk factor for depression in patients with TLE, and the correlation is significant. However, the sample size included in the study was small; additional high-quality studies are needed in the future.

Effects of long-term supplementation of probiotics on cognitive function and emotion in temporal lobe epilepsy

Cognitive impairment and neuropsychiatric disorders are very common in patients with temporal lobe epilepsy (TLE). These comorbidities complicate the treatment of epilepsy and seriously affect the quality of life. So far, there is still no effective intervention to prevent the development of epilepsy-associated comorbidities. Gut dysbiosis has been recognized to be involved in the pathology of epilepsy development. Modulating gut microbiota by probiotics has shown an antiseizure effect on humans and animals with epilepsy. Whether this treatment strategy has a positive effect on epilepsy-associated comorbidities remains unclear. Therefore, this study aimed to objectively assess the effect of probiotics on cognitive function and neuropsychiatric performance of patients with TLE. Participants enrolled in an epilepsy clinic were randomly assigned to the probiotic and placebo groups. These two groups were treated with probiotics or placebo for 12 weeks, and then the cognitive function and psychological performance of participants were assessed. We enrolled 76 participants in this study, and 70 subjects were finally included in the study (35 in the probiotics group and 35 in the placebo group). Our results showed significant seizure reduction in patients with TLE treated with probiotics. No significant differences were observed on cognitive function (including intelligence and memory) between groups. For neuropsychiatric performances, supplementation of probiotics significantly decreased the Hamilton Anxiety Rating and Depression Scale scores and increased the 89-item Quality of Life in Epilepsy Inventory score in patients with TLE. In conclusion, probiotics have a positive impact on seizures control, and improve anxiety, depression, and quality of life in patients with TLE.

Do Hippocampal Neurons Really Count for Comorbid Depression in Patients With Mesial Temporal Lobe Epilepsy and Hippocampal Sclerosis? A Histopathological Study

Depression is the most frequent psychiatric comorbidity seen in mesial temporal lobe epilepsy (MTLE) patients with hippocampal sclerosis (HS). Moreover, the HS is the most frequent pathological hallmark in MTLE-HS. Although there is a well-documented hippocampal volumetric reduction in imaging studies of patients with major depressive disorder, in epilepsy with comorbid depression, the true role of the hippocampus is not entirely understood. This study aimed to verify if patients with unilateral MTLE-HS and the co-occurrence of depression have differences in neuronal density of the hippocampal sectors CA1-CA4. For this purpose, we used a histopathological approach. This was a pioneering study with patients having both clinical disorders. However, we found no difference in hippocampal neuronal density when depression co-occurs in patients with epilepsy. In this series, CA1 had the lowest counting in both groups, and HS ILAE Type 1 was the most prevalent. More studies using histological assessments are needed to clarify the physiopathology of depression in MTLE-HS.

Prevalence and associated risk factors of undiagnosed depression among people with epilepsy in a multiethnic society

BACKGROUND

Depression is the most frequent psychiatric comorbidity of epilepsy. However, clinicians often neglect to screen for depressive symptoms among patients with epilepsy and, therefore, fail to detect depression. Many studies have described the risks associated with depression in patients with epilepsy, but few studies have elaborated whether these risks are similar in those with undiagnosed depression, especially in a multiethnic community.

METHODS

In the present cross-sectional study conducted at a tertiary teaching hospital, we aimed to investigate the prevalence and associated risk factors of undiagnosed depression in patients with epilepsy. We recruited patients with epilepsy aged 18-65 years after excluding those with background illnesses that may have contributed to the depressive symptoms. In total, 129 participants were recruited. We collected their demographic and clinical details before interviewing them using two questionnaires-the Neurological Disorders Depression Inventory for Epilepsy and Beck's Depression Inventory-II. Subsequently, if a participant screened positive for depression, the diagnosis was confirmed using the Diagnostic and Statistical Manual of Mental Disorders questionnaire, and a psychiatric clinic referral was offered.

RESULTS

Among the 129 participants, 9.3 % had undiagnosed major depressive disorder, and there was a female preponderance (66.7 %). The risk factors for undiagnosed depression among patients with epilepsy included low socioeconomic background (p = 0.026), generalized epilepsy (p = 0.036), and temporal lobe epilepsy (p = 0.010). Other variables such as being underweight and unmarried were more common among patients diagnosed with depression than without but no statistically significant relationship was found.

CONCLUSION

The prevalence of undiagnosed depression among patients with epilepsy was higher than that in population-based studies conducted in Western countries. Although questionnaires to screen for depression are widely available, some clinicians rarely use them and, therefore, fail to identify patients who may benefit from psychosocial support and treatment that would improve their disease outcomes and quality of life. The present study indicated that clinicians should use screening questionnaires to identify undiagnosed depression in people with epilepsy.

A pioneering FreeSurfer volumetric study of a series of patients with mesial temporal lobe epilepsy and hippocampal sclerosis with comorbid depression

Depression is the most frequent psychiatric comorbidity in patients with mesial temporal lobe epilepsy (MTLE) and hippocampal sclerosis (HS). This study aimed to confirm whether patients with comorbid depression have different volumetric patterns on magnetic resonance imaging, analysing the influence of HS sides. Psychiatrists conducted semi-structured interviews with 75 patients, who were divided into non-depression group (NDG, n = 52) and depression group (DG, n = 23), and compared with 98 controls. The FreeSurfer software was used in the volumetric analysis of the estimated total intracranial volume (eTIV), bilateral cortical and subcortical regions of interest (ROIs), and for presence of left (L-, n = 41) or right (R-, n = 34) MTLE-HS. Twenty-three (30.7%) patients had depression, of whom 14 (34.1%) had l-MTLE-HS and 9 (26.5%) had R-MTLE-HS. No difference was observed between DG and NDG vs. controls in terms of eTIV and cortical ROIs, regardless of the severity of depression. In patients with l-MTLE-HS, the eTIV in the DG was reduced in comparison with that in the NDG and control group, with a small effect size. Hippocampal reduction occurred ipsilateral to HS in the l-MTLE-HS and R-MTLE-HS subgroups when DG and NDG were compared with controls, as expected according to Enhancing Neuro Imaging Genetics through Meta-Analysis (2018).

Anxiety and depressive symptoms long after mesial temporal epilepsy surgery: A prospective study

BACKGROUND

Anxiety and depressive symptoms are prevalent in patients with refractory mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) before and after anterior temporal lobectomy (ATL).

AIMS

(1) To follow the levels of anxiety and depressive symptoms long-term after ATL among patients with refractory MTLE-HS; (2) To identify pre- and postsurgical variables associated with the levels of anxiety and depressive symptoms after surgery.

METHODS

We compared the levels of anxiety and depressive symptoms determined by the Hospital Anxiety and Depression Scale (HADS) before and long after ATL (mean 104 months, range 70-130) in 41 consecutive patients refractory MTLE-HS. The last follow-up was between September 2018 and March 2020. We also determined pre- and postsurgical variables independently associated with the HADS scores after surgery.

RESULTS

The scores of HADS and its subdomains related to anxiety and depression decreased significantly (p < 0.01) after ATL. After multiple linear regressions, the HADS-Anxiety scores before surgery (B = 0.47, CI 95% 0.20 to 0.75, p = 0.001) and at follow-up after surgery (B = 0.07, CI 0.00 to 0.14, p = 0.05) remain independently and positively associated with HADS-Anxiety scores after surgery. The HADS-Depression scores after surgery were independently positively associated with HADS-Depression scores before surgery (B = 0.39, CI 95% 0.10 to 0.76, p = 0.01) and worse seizure control after surgery (B = 1.55, CI 95% 0.23 to 2.87, p = 0.02).

CONCLUSION

Anxiety and depressive symptoms in patients with MTLE-HS significantly improved after ATL. Presurgical levels of anxiety and depressive symptoms, respectively, were positively associated with the postsurgical levels of those symptoms. Length of follow-up is associated with anxiety, and worse seizure control is associated with depressive symptoms after ATL. The results have implications for the surgical management of MTLE-HS patients.

Recent Advances in Neuroimaging of Epilepsy

Human neuroimaging has had a major impact on the biological understanding of epilepsy and the relationship between pathophysiology, seizure management, and outcomes. This review highlights notable recent advancements in hardware, sequences, methods, analyses, and applications of human neuroimaging techniques utilized to assess epilepsy. These structural, functional, and metabolic assessments include magnetic resonance imaging (MRI), positron emission tomography (PET), and magnetoencephalography (MEG). Advancements that highlight non-invasive neuroimaging techniques used to study the whole brain are emphasized due to the advantages these provide in clinical and research applications. Thus, topics range across presurgical evaluations, understanding of epilepsy as a network disorder, and the interactions between epilepsy and comorbidities. New techniques and approaches are discussed which are expected to emerge into the mainstream within the next decade and impact our understanding of epilepsies. Further, an increasing breadth of investigations includes the interplay between epilepsy, mental health comorbidities, and aberrant brain networks. In the final section of this review, we focus on neuroimaging studies that assess bidirectional relationships between mental health comorbidities and epilepsy as a model for better understanding of the commonalities between both conditions.

A systematic review of neuroimaging studies of depression in adults with epilepsy

OBJECTIVE

Depression is a relatively common comorbidity in people with epilepsy with a lifetime history identified in 1 in 4 individuals. In this paper, we aimed to provide a systematic review of structural and functional brain region-specific group differences of adults with epilepsy and depression and to discuss existing evidence as compared to that in people with depression.

METHODS

We undertook a systematic review of neuroimaging studies of depression in adults with epilepsy through MEDLINE/PubMed, Embase and PsycInfo searches until June 2020.

RESULTS

A total of 44 studies were included in the qualitative synthesis: 21 on structural neuroimaging, 9 on functional, and 14 on pharmaco/metabolic neuroimaging. Almost all studies focused on temporal lobe epilepsy (TLE). Patterns of changes in the hippocampi and subcortical structures seem to be different from those reported in depression outside epilepsy. Cortical changes are grossly similar as well as the lack of any laterality effect. Serotonin dysfunction seems to be due to different mechanisms with reduced synaptic availability for depression in epilepsy as compared to reduced 5HT1 receptor density outside epilepsy. Depressive symptoms seem to correlate with a dysfunction in temporolimbic structures contralateral to the epileptogenic zone especially in patients with de novo postsurgical depression.

CONCLUSIONS

Depression, at least in TLE, seems to be associated with a different pattern of brain changes as compared to major depression, potentially supporting the notion of phenomenological peculiarities of depression in epilepsy.

Psychiatric Comorbidities in Pediatric Epilepsy

PURPOSE OF REVIEW

Psychiatric comorbidities are close to 5-times higher in children and youth with epilepsy (CYE) compared to general population. With epilepsy being one of the most common neurological disorders in children, we provide a timely review of psychiatric issues in CYE.

RECENT FINDINGS

A meta-analysis found a pooled prevalence of anxiety in 18.9% and depression in 13.5% of CYE. Attention deficit hyperactivity disorder (ADHD) is 2.5 to 5.5 times higher in CYE compared to healthy counterparts. Recent evidence highlights that behavioral adverse effects may lead to discontinuation of anti-epileptic drugs (AEDs) in more than 10% of CYE. Up to 70% CYE shows elevation in baseline psychological symptoms after AED initiation. Identifying psychiatric symptoms can be easily accomplished by the routine use of psychiatric screening instruments in CYE clinics, which is associated with improved health-related quality of life (HRQOL). Psychoeducation is a key component for any visit with CYE. There is some evidence of the effectiveness of behavioral psychological interventions for CYE. There are no therapeutic trials of psychotropics in CYE, but treatment recommendations based on the experience in adults with epilepsy and general population are applicable. Early diagnosis and management of psychiatric comorbidities leads to improvement in HRQOL of CYE. This requires routine screening and a multidisciplinary teamwork.

Neuropsychological findings related to the presence of pre-surgical comorbid depression in Latin-American patients with mesial temporal lobe epilepsy and hippocampal sclerosis

PURPOSE

To evaluate the neuropsychological findings related to the presence of pre-surgical comorbid depression in Latin-American patients with mesial temporal lobe epilepsy (MTLE) and unilateral hippocampal sclerosis (HS).

METHOD

Patients with drug-resistant MTLE and unilateral, left (L-) or right (R-) HS were studied. To diagnose depression, psychiatrists with expertise in epilepsy applied a semi-structured interview based on DSM. The depression group (DG) included patients with a psychiatric diagnosis in addition to a Beck Depression Inventory (BDI) score >16 points, and the non-depression group (NDG) included those without this diagnosis and with a BDI score ≤16. We analysed two clusters of neuropsychological tests, which evaluated memory (Complex Rey Figure III, Logical Memory II and RAVLT VII) and attention plus executive functions (Stroop I/II/III and Trail Making A/B). Moreover, we calculated the z-scores (Zs) using a local control group. The DG was compared to the NDG, independently and according to the HS side, using non-parametrical analyses. Due to the multivariate analysis, the p-value was corrected by applyingpost hoc Bonferroni adjustment.

RESULTS

We analysed 65 patients. The NDG included 51 (78.4 %) patients, and the DG included 14 (21.5 %) patients. Pre-surgical comorbid depression occurred in eight patients with L- (n = 29) and in six patients with R-MTLE-HS (n = 36). All of these groups had similar gender, age, IQs, and years of schooling. Compared to the healthy subjects, the L-MTLE-HS patients had lower Zs in verbal episodic memory tests [Logical Memory II (p < 0.001), and RAVLT VII (p < 0.001)], and the R-MTLE-HS patients had lower scores in visual episodic memory [Complex Rey Figure III (p < 0.001)]. In the analysis of the DGvs. NDG, there were no differences in the clusters of tests of memory or in those of attention and executive functions. Moreover, when we analysed the patients according to HS side, no neuropsychological difference was observed in the DG and NDG in terms of L- and R-MTLE-HS.

CONCLUSIONS

The patients with MTLE and unilateral HS in this study showed no differences in memory, attention and executive functions in relation to the presence of pre-surgical comorbid depression and independently of HS side. In this series from Latin-America, this psychiatric comorbidity did not affect cognition more than epilepsy alone.

Network Dysfunction in Comorbid Psychiatric Illnesses and Epilepsy

The episodic nature of both epilepsy and psychiatric illnesses suggests that the brain switches between healthy and pathological states. The most obvious example of transitions between network states related to epilepsy is the manifestation of ictal events. In addition to seizures, there are more subtle changes in network communication within and between brain regions, which we propose may contribute to psychiatric illnesses associated with the epilepsies. This review will highlight evidence supporting aberrant network activity associated with epilepsy and the contribution to cognitive impairments and comorbid psychiatric illnesses. Further, we discuss potential mechanisms mediating the network dysfunction associated with comorbidities in epilepsy, including interneuron loss and hypothalamic–pituitary–adrenal axis dysfunction. Conceptually, it is necessary to think beyond ictal activity to appreciate the breadth of network dysfunction contributing to the spectrum of symptoms associated with epilepsy, including psychiatric comorbidities.

Internalizing symptoms in intractable pediatric epilepsy: Structural and functional brain correlates

Internalizing disorders (i.e., depression and anxiety) are common comorbidities in people with epilepsy. In adults with epilepsy, comorbid depression or anxiety is associated with worse seizure control and reduced quality of life, and may be linked to specific neural biomarkers. Less is known about brain correlates of internalizing symptoms in pediatric populations. In the current study, we performed a retrospective analysis of 45 youth between the ages of 6 and 18 years old with intractable epilepsy. Individuals were evaluated for internalizing symptoms on the Child Behavior Checklist (CBCL) and underwent magnetic resonance (MR) and fluorodeoxyglucose (FDG)-positron emission tomography (PET) imaging as part of the clinical evaluation for surgical treatment of epilepsy. Forty-two percent of patients experienced clinically significant internalizing symptoms based on parent report. Compared with individuals who scored in the normal range, youth with clinical levels of internalizing problems showed overall reductions in cortex volume, as well as widespread reductions in cortical thickness and functional activation in the bilateral occipital/parietal lobe, left temporal regions, and left inferior frontal cortex on MR and PET scans. There were no group differences in amygdala or hippocampus volumes, nor other patient- or illness-related variables such as age, sex, or the type, lateralization, or duration of epilepsy. Results suggest that high rates of internalizing disorders are present in youth with refractory epilepsy. Multifocal reductions in cortical thickness and function may be nonspecific risk factors for clinically meaningful internalizing symptoms in youth with chronic epilepsy. As such, the presence of broad cortical thinning and reduced glucose uptake upon radiological examination may warrant more focused clinical evaluation of psychological symptoms.

Impact of surgical intervention on seizure and psychiatric symptoms in patients with temporal lobe epilepsy

Temporal lobe epilepsy (TLE), a common form of localisation-related epilepsy, is characterised by focal seizures and accompanied by variety of neuropsychiatric symptoms. This form of epilepsy proves difficult to manage as many anticonvulsant and psychotropic medications have little to no effect on controlling the seizure and neuropsychiatric symptoms respectively. The authors, report a patient with TLE and recurrent seizures that were refractory to multiple classes of antiepileptic therapy. Additionally, she exhibited psychosis, depression and irritability that required antipsychotic medication. After several years of poorly controlled seizure disorder, the patient underwent anterior temporal lobectomy and amygdalohippocampectomy, which proved beneficial for seizure control, as well as her neuropsychiatric symptoms. While it is common to treat refractory temporal lobe epilepsy with surgical interventions, there is little literature about it also treating the neuropsychiatric symptoms. This case underscores both the neurological and psychiatric benefits following surgical intervention for patients with TLE.

Anxiety is common and independently associated with clinical features of epilepsy

OBJECTIVE

The objective of this study was to assess for independent association of anxiety symptoms with epilepsy localization and other epilepsy-related and demographic factors in a large tertiary care adult epilepsy population.

METHODS

Among 540 adults, anxiety was measured by the Symptom Checklist 90-R (SCL-90R) anxiety subscale, and detailed demographics, epilepsy localization, and depression scores (SCL-90R) were collected. High anxiety was defined by SCL-90R anxiety T-score ≥ 60. Stepwise multiple logistic regression was carried out to assess for independent association of high anxiety scores with demographic and clinical factors.

RESULTS

High anxiety symptoms were present in 46.1% of participants (N = 250). Focal or unknown epilepsy type and depression scores were independently associated with high anxiety (adjusted odds ratios (OR): 2.89 (95% confidence interval [CI] = 1.33-6.29, p = 0.007) and 2.12 (95% CI = 1.83-2.45, p < 0.001), respectively; depression odds per 5-point increase in scale). Among the focal epilepsy subpopulation, mesial temporal sclerosis was also independently associated with high anxiety, with adjusted OR: 2.12 (95% CI = 1.11-4.04, p = 0.023). Lower education, non-white race/ethnicity, Spanish native language, prior head trauma, antiseizure drug polytherapy, and left focus or bilateral foci (in focal epilepsy) were associated with high anxiety in simple logistic regression, but these associations were not independent. A total of 46 individuals (18.4% of those with high anxiety) scored high for anxiety but not depression. Only 26% of those with high anxiety symptoms were taking a potentially anxiolytic medication.

CONCLUSION

Anxiety symptoms, often without concomitant depression, were highly prevalent in this epilepsy sample and independently associated with focal/unknown epilepsy and mesial temporal sclerosis. These results strongly support the value of screening specifically for anxiety in the epilepsy clinic, to direct patients to appropriate treatment.

Are mental distress and cognitive impairment related in temporal lobe epilepsy?

OBJECTIVE

Cognitive impairment and depression often co-exist among patients with epilepsy. However, there is still debate whether depression and cognition are related in patients with temporal lobe epilepsy (TLE). Even if they were related, it is still unclear whether symptoms of depression specifically, or rather symptoms of mental distress in general, have a negative impact on cognition in patients with TLE. In the present study, we examined whether self-rated symptoms of mental distress and of depression are related to different cognitive functions in unilateral TLE.

METHODS

We retrospectively studied 162 patients undergoing preoperative evaluation for epilepsy surgery (95 patients with left TLE (LTLE) and 67 patients with right TLE (RTLE)). Severity of mental distress and symptoms of depression were measured with the Symptom Checklist-90-Revised (SCL-90-R) and the Beck Depression Inventory (BDI), respectively. Bivariate correlations were calculated between these two measures and neuropsychological measures of verbal recall, figural learning, psychomotor speed, and phonemic word fluency. Due to multiple testing, a corrected level of p < 0.0063 was regarded as significant, only.

RESULTS

Seventeen and 19% of patients reported meaningful mental distress and meaningful symptoms of depression, respectively. Mental distress highly correlated with symptoms of depression (r_s = 0.80). We found no significant correlations of either mental distress or symptoms of depression with measures of cognitive function.

CONCLUSIONS

In contrast to some former studies with smaller sample sizes, the present study could not detect a relationship of depression with cognitive impairment in patients with unilateral TLE. Likewise, mental distress and cognition were unrelated in our sample of patients. Our results may argue against theoretical models claiming a causal link between depression and cognitive impairment or a common pathogenic mechanism for these conditions in patients with TLE.

The relationship of seizure focus with depression, anxiety, and health-related quality of life in children and adolescents with epilepsy

For youth with epilepsy, comorbid psychiatric conditions, such as depression and anxiety, require further examination as they carry increased risk for reduced health-related quality of life (HRQOL). The current study assessed whether rates of depression, anxiety, and withdrawal behaviors differed based on seizure location. Data included parental ratings on the Behavior Assessment System for Children (BASC-2) and the Quality of Life in Childhood Epilepsy (QOLCE) questionnaire for 132 children and adolescents (mean age=11.34, SD=3.95) with generalized or partial (i.e., frontal [FLE] or temporal lobe epilepsy [TLE]) epilepsy. Our results identified clinically significant internalizing psychopathology in nearly half of our sample (41%). Although rates of internalizing behavior were similar between generalized and partial groups, children and adolescents with TLE demonstrated higher rates of depression compared to youth with FLE. No effects of laterality on internalizing behaviors were identified between TLE and FLE groups. Finally, for youth with TLE, parental depression ratings along with current number of antiepileptic medications (AEDs) were found to be significant barriers to HRQOL above and beyond anxiety, withdrawal, and epilepsy-specific variables. Temporal lobe epilepsy was associated with a two-fold risk of clinically significant depression ratings. These findings highlight the high prevalence of internalizing psychopathology features in pediatric epilepsy and offer further support for the relationship between depression and TLE in children and adolescents with epilepsy.

Prevalence of depression and anxiety among patients with epilepsy attending the epilepsy clinic at Sheikh Khalifa Medical City, UAE: A cross-sectional study

Depression and anxiety are highly prevalent in patients with epilepsy (PWE), with prevalence rates ranging from 20% to 55%. Unfortunately, the rates, patterns, and risk factors have not been well studied in the Middle East and, to our knowledge, have not been studied at all in the UAE. We screened 186 patients attending an epilepsy clinic using standardized screening tools to determine the rates of both depression and anxiety and compared these rates with that of age- and sex-matched controls. Almost one-third of our patients scored in the depression and anxiety ranges, which was significantly higher compared with the age- and sex-matched controls. Using a multiregression model, none of the studied variables were associated with an increased risk of having either disorder. Depression or anxiety symptoms independently and significantly increased the risk of association with the other disorder. Almost two-thirds of patients with depression and anxiety were not prescribed antidepressant or antianxiety medications.

Alterations in functional connectivity between the hippocampus and prefrontal cortex as a correlate of depressive symptoms in temporal lobe epilepsy

Depression is a common comorbidity in temporal lobe epilepsy (TLE) that is thought to have a neurobiological basis. This study investigated the functional connectivity (FC) of medial temporal networks in depression symptomatology of TLE and the relative contribution of structural versus FC measures. Volumetric MRI and functional connectivity MRI (fcMRI) were performed on nineteen patients with TLE and 20 controls. The hippocampi and amygdalae were selected as seeds, and five prefrontal and five cingulate regions of interest (ROIs) were selected as targets. Low-frequency blood-oxygen-level-dependent signals were isolated from fcMRI data, and ROIs with synchronous signal fluctuations with the seeds were identified. Depressive symptoms were measured by the Beck Depression Inventory-II. The patients with TLE showed greater ipsilateral hippocampal atrophy (HA) and reduced FC between the ipsilateral hippocampus and the ventral posterior cingulate cortex (vPCC). Neither HA nor hippocampal-vPCC FC asymmetry was a robust contributor to depressive symptoms. Rather, hippocampal-anterior prefrontal FC was a stronger contributor to depressive symptoms in left TLE (LTLE). Conversely, right amygdala FC was correlated with depressive symptoms in both patient groups, with a positive and negative correlation in LTLE and right TLE (RTLE), respectively. Frontolimbic network dysfunction is a strong contributor to levels of depressive symptoms in TLE and a better contributor than HA in LTLE. In addition, the right amygdala may play a role in depression symptomatology regardless of the side of the epileptogenic focus. These findings may inform the treatment of depressive symptoms in TLE and inspire future research to help guide surgical planning.