Psychiatric history does not predict seizure outcome following temporal lobectomy for mesial temporal sclerosis

Surgery procedures in temporal lobe epilepsies

Temporal lobe epilepsy (TLE) is the most common cause of refractory epilepsy amenable for surgical treatment and seizure control. Surgery for TLE is a safe and effective strategy. The seizure-free rate after surgical resection in patients with mesial or neocortical TLE is about 70%. Resective surgery has an advantage over stereotactic radiosurgery in terms of seizure outcomes for mesial TLE patients. Both techniques have similar results for safety, cognitive outcomes, and associated costs. Stereotactic radiosurgery should therefore be seen as an alternative to open surgery for patients with contraindications for or with reluctance to undergo open surgery. Laser interstitial thermal therapy (LITT) has also shown promising results as a curative technique in mesial TLE but needs to be more deeply evaluated. Brain-responsive stimulation represents a palliative treatment option for patients with unilateral or bilateral MTLE who are not candidates for temporal lobectomy or who have failed a prior mesial temporal lobe resection. Overall, despite the expansion of innovative techniques in recent years, resective surgery remains the reference treatment for TLE and should be proposed as the first-line surgical modality. In the future, ultrasound therapies could become a credible therapeutic option for refractory TLE patients.

Association Between Psychiatric Comorbidities and Mortality in Epilepsy

Objective

To explore the impact of psychiatric comorbidities on all-cause mortality in adults with epilepsy from a cohort of patients admitted for video-EEG monitoring (VEM) over 2 decades.

Methods

A retrospective medical record audit was conducted on 2,709 adults admitted for VEM and diagnosed with epilepsy at 3 Victorian comprehensive epilepsy programs from 1995 to 2015. A total of 1,805 patients were identified in whom the record of a clinical evaluation by a neuropsychiatrist was available, excluding 27 patients who died of a malignant brain tumor known at the time of VEM admission. Epilepsy and lifetime psychiatric diagnoses were determined from consensus opinion of epileptologists and neuropsychiatrists involved in the care of each patient. Mortality and cause of death were determined by linkage to the Australian National Death Index and National Coronial Information System.

Results

Compared with the general population, mortality was higher in people with epilepsy (PWE) with a psychiatric illness (standardized mortality ratio [SMR] 3.6) and without a psychiatric illness (SMR 2.5). PWE with a psychiatric illness had greater mortality compared with PWE without (hazard ratio 1.41, 95% confidence interval 1.02-1.97) after adjusting for age and sex. No single psychiatric disorder by itself conferred increased mortality in PWE. The distribution of causes of death remained similar between PWE with psychiatric comorbidities and those without.

Conclusion

The presence of comorbid psychiatric disorders in adults with epilepsy is associated with increased mortality, highlighting the importance of identifying and treating psychiatric comorbidities in these patients.

Can We Anticipate and Prevent the Occurrence of Iatrogenic Psychiatric Events Caused by Anti-seizure Medications and Epilepsy Surgery?

Psychiatric disorders and behavioral manifestations in patients with epilepsy have complex and multifactorial etiologies. The psychotropic properties of anti-seizure medications (ASMs) and psychiatric effects of epilepsy surgery can result in iatrogenic psychiatric symptoms or episodes or can yield a therapeutic effect of underlying psychiatric disorders and have a significant impact on the patients' quality of life. The aims of this chapter are to review the available evidence of psychotropic properties of ASMs, which may be responsible for iatrogenic psychiatric symptoms and/or disorders. Moreover, the several aspects associated with the impact of epilepsy surgery on the possible improvement/development of psychiatric disorders were addressed.

Psychiatric and psychosocial morbidity 1 year after epilepsy surgery

OBJECTIVES

There is a high rate of psychiatric comorbidity in patients with epilepsy. However, the impact of surgical treatment of refractory epilepsy on psychopathology remains under investigation. We aimed to examine the impact of epilepsy surgery on psychopathology and quality of life at 1-year post-surgery in a population of patients with epilepsy refractory to medication.

METHODS

This study initially assessed 48 patients with refractory epilepsy using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), the Hospital Anxiety and Depression Scale (HADS) and the Quality of Life in Epilepsy Inventory 89 (QOLIE-89) on admission to an Epilepsy Monitoring Unit (EMU) as part of their pre-surgical assessment. These patients were again assessed using the SCID-I, QOLIE-89 and HADS at 1-year follow-up post-surgery.

RESULTS

There was a significant reduction in psychopathology, particularly psychosis, following surgery at 1-year follow-up (p < 0.021). There were no new cases of de novo psychosis and surgery was also associated with a significant improvement in the quality of life scores (p < 0.001).

CONCLUSIONS

This study demonstrates the impact of epilepsy surgery on psychopathology and quality of life in a patient population with refractory surgery. The presence of a psychiatric illness should not be a barrier to access surgical treatment.

Psychiatric disorders as predictors of epilepsy surgery outcome

OBJECTIVES

Our aim was to determine if a history of a mental disorder predicts a worst neurological outcome for patients undergoing epilepsy surgery.

METHODS

We conducted an ambispective observational study including people with refractory epilepsy who underwent resective surgery. Demographic, psychiatric, and neurological data were collected, before and one year after surgery. Presurgical interviews included a psychiatric evaluation and the determination of prevalent and lifetime psychiatric diagnosis. The one-year postsurgical outcome was classified according to the Engel Outcome Scale. Predictors of postsurgical Engel class were determined using an ordered logistic regression model.

RESULTS

A lifetime history of any mental disorder was a significant predictor of a higher Engel Class (p = 0.017).

CONCLUSION

This study shows that psychiatric lifetime diagnoses are associated with worse surgical outcome and highlighted the importance of the inclusion of these diagnoses in the evaluation of the potential success of the surgery.

Presurgical depression and anxiety are not associated with worse epilepsy surgery outcome five years postoperatively

PURPOSE

Anxiety and depression have been associated with poor seizure control after epilepsy surgery. This study explored the effect of presurgical anxiety or depression on two- and five-year seizure control outcomes.

METHODS

Adult subjects were enrolled between 1996 and 2001 in a multicenter prospective study to evaluate outcomes of resective epilepsy surgery. A Poisson regression was used to analyze the association of depression and anxiety with surgical outcome, while adjusting for gender, age, ethnicity, number of years with seizures, and presence of mesial temporal sclerosis.

RESULTS

The relative risk (RR) of presurgical depression on two-year seizure-free outcome in this cohort is 1.12 (95% confidence interval (CI), 0.84-1.49) and 1.06 (CI, 0.73-1.55) on five-year seizure free outcome. The RR of presurgical anxiety on two-year seizure outcome is 0.73 (CI, 0.50-1.07) and 0.70 (CI, 0.43-1.17) on five-year seizure outcome. When including Engel classes I and II, the RRs of presurgical depression, anxiety, or both two years after surgery were 0.96 (p=0.59), 0.73 (p<0.05), and 0.97 (p=0.70), respectively, and they were 0.97 (p=0.82), 0.84 (p=0.32), and 0.89 (p=0.15), respectively, five years after surgery. Only presurgical anxiety was associated with worse epilepsy surgery outcome two year after surgery but not at five years postsurgery. Depression was not a risk factor for poor epilepsy surgical outcome in the long term.

CONCLUSION

These findings from a prospective study that utilized a standardized protocol for psychiatric and seizure outcome assessment suggest that presurgical mood disorders have no substantial impact on postsurgical seizure outcome for up to five years after surgery.

Psychiatric lifetime diagnoses are associated with a reduced chance of seizure freedom after temporal lobe surgery

OBJECTIVE

To examine whether psychiatric comorbidity is a predictor of long-term seizure outcome following temporal lobe epilepsy surgery.

METHODS

A sample of 434 adult patients who received temporal lobe resection to treat epilepsy between 1991 and 2009 and were psychiatrically assessed before surgery were followed for 2 years to assess seizure outcome. Stepwise multivariate logistic regression analyses were used to assess the impact of psychiatric variables on complete seizure freedom (Engel class IA), and freedom from disabling seizures (Engel class I). Lifetime histories of three psychiatric syndromes (PS: psychosis; depression; other) and five personality disorders (PD: DSM-IV Clusters A, B, and C; organic personality disorder; other) were considered as predictors, complemented by age at onset, duration of epilepsy, type of lesion (mesiotemporal sclerosis vs. other), and year of surgery.

RESULTS

Seizure-freedom rates were significantly higher (p < 0.001) in patients with no history of PS or PD (N = 138; Engel class IA: 61.6%; Engel class I: 87.7%) than in those with any PS or PD (N = 296; Engel class IA: 39.5%; Engel class I: 58.8%). Particularly low seizure-freedom rates were found in patients with a diagnosis of psychosis (N = 32, Engel class IA: 21.9%; Engel class I: 40.6%), organic PD (N = 48, Engel class IA: 25.0%; Engel class I: 35.4%) or a double diagnosis of PS plus PD (N = 97; Engel class IA: 27.8%; Engel class I: 45.5%). No other variables emerged as significant risk factors in multivariate logistic regression analyses.

SIGNIFICANCE

Patients with and without psychiatric comorbidities can benefit from temporal lobe epilepsy surgery; however, psychiatric comorbidities are negatively associated with postoperative seizure-freedom rates. Surgical outcome is related to the type and extent of preoperative psychiatric morbidity, which underscores the prognostic value of presurgical psychiatric evaluation. The data support the argument that there are common pathogenetic mechanisms underlying both epilepsy and psychiatric conditions.

Epilepsy-related psychoses and psychotic symptoms are significantly reduced by resective epilepsy surgery and are not associated with surgery outcome or epilepsy characteristics: A cohort study

We examine epilepsy-related psychoses and psychotic symptoms (ERPs) and the effects of epilepsy surgery on inter-ictal, aura, ictal and peri-ictal (pre- and post-ictal) psychoses. We included 189 patients with refractory epilepsy both before and 24 months after surgery. Engel's classification was the primary outcome measurement. Epilepsy surgery reduced the prevalence of ERPs from 17.5% to 4.2%, psychotic aura from 7.9% to 0.5%, ictal psychoses from 3.7% to 1.1% and peri-ictal psychoses from 4.2% to 0.5%. The prevalence of inter-ictal psychoses decreased from 5.3% to 0.5%, but 4 new cases of inter-ictal psychoses were found following surgery. Interictal dysphoric disorder significantly predicted surgery outcome. In patients with and without ERPs, epilepsy surgery induced seizure reduction in more than 90% of the cases, showing that both groups benefit equally from surgery. No associations between ERPs and epileptic characteristics were found, including laterality, type of lesion, type of epilepsy, number of seizures, duration of illness or age at onset. Epilepsy surgery significantly improves ERPs particularly psychotic aura and peri-ictal psychoses. Although inter-ictal psychoses are successfully treated, new inter-ictal psychoses appear in a few cases either as alternative psychoses or a possible switch from pre-surgery episodic into inter-ictal psychoses.

Life outcomes of anterior temporal lobectomy: serial long-term follow-up evaluations

BACKGROUND

At 3 time points, this study examined long-term psychosocial life outcomes of individuals who underwent anterior temporal lobectomy in comparison with individuals with temporal lobe epilepsy who were medically managed.

OBJECTIVE

To examine seizure frequency, employment, driving, independent living, financial independence, mental health, and quality of life at each follow-up assessment, as well as predictors of outcomes.

METHODS

All participants were diagnosed with medically intractable complex partial seizures of temporal lobe origin with or without secondary generalization. A structured clinical interview was used at all 3 time points. Information was obtained regarding seizure frequency, antiepilepsy medications, employment, driving status, financial assistance, and independent living. Additionally, questions regarding quality of life, satisfaction with surgery, and the presence of depression or anxiety were included. Participants were, on average, 17 years postsurgery.

RESULTS

Surgery resulted in significantly improved and sustained seizure outcomes. At the first, second, and third follow-ups, 67%, 72%, and 67% of participants in the surgery group remained seizure-free in the year before the follow-up interview. At each follow-up, 97%, 84%, and 84% reported that they would undergo surgery again. Seizure freedom predicted driving outcomes at all 3 time points, but was not a significant predictor for employment, independent living, or financial independence. Psychosocial life outcomes in the surgical group were improved and maintained over time in comparison with the medically managed group.

CONCLUSION

This systematic long-term investigation provides strong support for the positive impact of anterior temporal lobectomy on psychosocial life outcomes including driving, employment, independent living, and financial independence.

Severe hippocampal atrophy is not associated with depression in temporal lobe epilepsy

Depression in temporal lobe epilepsy (TLE) is common, is a strong predictor of subjective disability, and may have unique pathophysiological characteristics. Previous studies showed that reduced hippocampal volume is associated with significant depressive symptoms in patients with TLE. We utilized regions of interest analysis of high-resolution brain MRI and a reliable and valid measure of depressive symptoms to evaluate 28 consecutive adult subjects with video-EEG-confirmed TLE. Regions of interest were based on prior human and animal studies of mood and behavioral dysfunction. Forty-three percent of the entire group had significant symptoms of depression, defined by a Beck Depression Inventory (BDI) score of greater than 15. Total hippocampal volumes were significantly smaller in the group with BDI<15, (p<0.007). None of the subjects in the quartile with the smallest left hippocampal volume had a BDI score greater than 15 compared with 57% of the subjects in the upper three quartiles (p<0.008). No other limbic brain structures (amygdala, subcallosal gyrus, subgenual gyrus, gyrus rectus), or total cerebral volume were associated with depressive symptoms. Adequate hippocampal integrity may be necessary to maintain depression symptoms in mesial temporal lobe epilepsy. This finding also supports the possibility of a unique mechanism for depression in mesial temporal lobe epilepsy, such as hyperexcitable neuronal influence on the limbic network.

Clinical predictors of 2-year outcome of resective epilepsy surgery in adults with refractory epilepsy: a cohort study

OBJECTIVES

Resective epilepsy surgery is currently a standard treatment for intractable epilepsy. Seizure freedom and discontinuation of antiepileptic drugs are the ultimate goals of epilepsy treatment. This study was carried out to delineate (1) possible differences in the success rate of epilepsy surgery 6 and 24 months after surgery; and (2) the clinical predictors of a good response to surgery.

SETTING

This is a cohort study performed at a tertiary care unit of a university hospital.

PARTICIPANTS

In this cohort study, 189 adults with intractable epilepsy who underwent epilepsy surgery were included. We collected clinical data at three time points, that is, preoperative and 6 and 24 months after surgery.

PRIMARY AND SECONDARY OUTCOME MEASURES

Engel class I-IV classification was the primary outcome measure of epilepsy surgery. The authors statistically adjusted Engel class I-IV classification for postoperative changes in antiepileptic drugs and used this new classification as a secondary outcome variable.

RESULTS

The success rate was 78.8% 6 months after surgery and increased to 88.3% 24 months after surgery. This success rate was reflected not only by the reduced number of seizures postsurgery, but also by a reduced dosage and use of antiepileptic drugs. Logistic regression analysis showed that a successful outcome of surgery is predicted by having temporal rather than extratemporal lobe epilepsy and less than nine presurgery seizures per month, while a positive familial history of epilepsy, younger age and dysphoric symptoms, the first 3 months after surgery, significantly worsened the outcome of surgery. Duration of illness, age at onset, epilepsy location, type of lesions and the presence of psychosis were not significant in predicting treatment outcome.

CONCLUSIONS

These findings have clinical relevance in that a better selection of patients based on the significant clinical predictors will increase the success rate of epilepsy surgery and treatment.

Disentangling the relationship between epilepsy and its behavioral comorbidities - the need for prospective studies in new-onset epilepsies

It has been long recognized that there is more to epilepsy than seizures. The prevalence of such neurobehavioral abnormalities as cognitive and mood disorders, autism spectrum disorder, and attention deficit and hyperactivity disorder (ADHD) is significantly higher among patients with epilepsy than in the general population. A long-held view that comorbidities of epilepsy represent mere epiphenomena of seizures has undergone substantial transformation during the past decade, as emerging clinical evidence and experimental evidence suggest the involvement of specific neurobiological mechanisms in the evolution of neurobehavioral deficits in patients with epilepsy. Developmental aspects of both epilepsy and its comorbidities, as well as the frequently reported reciprocal connection between these disorders, both add other dimensions to the already complex problem. In light of progress in effective seizure management in many patients with epilepsy, the importance of neurobehavioral comorbidities has become acute, as the latter are frequently more detrimental to patients' quality of life compared with seizures. This calls for a serious increase in efforts to effectively predict, manage, and ideally cure these comorbidities. Coordinated multicenter clinical, translational, and basic research studies focusing on epidemiology, neuropsychology, neurophysiology, imaging, genetics, epigenetics, and pharmacology of neurobehavioral comorbidities of epilepsy are absolutely instrumental for ensuring tangible progress in the field. Clinical research should focus more on new-onset epilepsy and put particular emphasis on longitudinal studies in large cohorts of patients and groups at risk, while translational research should primarily focus on the development of valid preclinical systems which would allow investigating the fundamental mechanism of epilepsy comorbidities. The final goal of the described research efforts would lie in producing an armamentarium of evidence-based diagnostic tools and therapeutic interventions which would at minimum mitigate and at maximum prevent or abolish neurobehavioral comorbidities of epilepsy and, thus, improve the quality of life of those patients with epilepsy who suffer from the said comorbidities.

Epilepsy, cognition, and neuropsychiatry (Epilepsy, Brain, and Mind, part 2)

Epilepsy is, of course, not one disease but rather a huge number of disorders that can present with seizures. In common, they all reflect brain dysfunction. Moreover, they can affect the mind and, of course, behavior. While animals too may suffer from epilepsy, as far as we know, the electrical discharges are less likely to affect the mind and behavior, which is not surprising. While the epileptic seizures themselves are episodic, the mental and behavioral changes continue, in many cases, interictally. The episodic mental and behavioral manifestations are more dramatic, while the interictal ones are easier to study with anatomical and functional studies. The following extended summaries complement those presented in Part 1.

Antidepressant therapy in epilepsy: can treating the comorbidities affect the underlying disorder?

There is a high incidence of psychiatric comorbidity in people with epilepsy (PWE), particularly depression. The manifold adverse consequences of comorbid depression have been more clearly mapped in recent years. Accordingly, considerable efforts have been made to improve detection and diagnosis, with the result that many PWE are treated with antidepressant drugs, medications with the potential to influence both epilepsy and depression. Exposure to older generations of antidepressants (notably tricyclic antidepressants and bupropion) can increase seizure frequency. However, a growing body of evidence suggests that newer ('second generation') antidepressants, such as selective serotonin reuptake inhibitors or serotonin-noradrenaline reuptake inhibitors, have markedly less effect on excitability and may lead to improvements in epilepsy severity. Although a great deal is known about how antidepressants affect excitability on short time scales in experimental models, little is known about the effects of chronic antidepressant exposure on the underlying processes subsumed under the term 'epileptogenesis': the progressive neurobiological processes by which the non-epileptic brain changes so that it generates spontaneous, recurrent seizures. This paper reviews the literature concerning the influences of antidepressants in PWE and in animal models. The second section describes neurobiological mechanisms implicated in both antidepressant actions and in epileptogenesis, highlighting potential substrates that may mediate any effects of antidepressants on the development and progression of epilepsy. Although much indirect evidence suggests the overall clinical effects of antidepressants on epilepsy itself are beneficial, there are reasons for caution and the need for further research, discussed in the concluding section.