Antiepileptic drugs and mood stability

The impact of lacosamide on mood disorders in adult patients with epilepsy: A systematic review

Mood disorders such as depression and anxiety have a high prevalence in adult patients with epilepsy, and their evaluation is crucial in choosing the most appropriate antiepileptic drug (AED) with regard to side effects, which can account for long-term discontinuation, poor compliance, and ultimately, failure of seizure control. While more evidence is provided for older AEDs on their effect on mood changes, newer AEDs such as lacosamide have not yet been extensively studied. We performed a systematic review of the literature available on the impact of lacosamide on mood in adult patients with epilepsy. A literature search on MEDLINE, COCHRANE, Scielo, and Clinicaltrials.gov databases was performed, and articles where mood scales where specifically reported as primary or secondary outcome measures were included. Articles differed greatly in terms of inclusion criteria, concomitant AEDs, seizure reduction control, and outcome measures. If lacosamide is used as add-on, two studies point towards a beneficial effect on depressive and anxiety symptoms, two studies claim no effects on mood, and one reports a positive effect only in patients with major depressive symptoms at baseline. Additional evidence from either retrospective or comparative drug studies indicates no effects of lacosamide on mood. Even though presently, a negative effect on mood seems unlikely, whether lacosamide could exert a beneficial impact on mood remains controversial. Multicenter, randomized, controlled, double-blind studies are needed to assess the impact on lacosamide on mood disorders, given the low evidence level (Class III and IV) of currently available studies.

Pharmacogenetics of carbamazepine

Carbamazepine (CMZ) is a drug from the group of anticonvulsants, similar in chemical structure to tricyclic antidepressants. CMZ is widely used for mental disorders and neurological diseases. The lecture discusses the safety of CMZ in respect to personalized medicine, while considering the pharmacogenetic profile of the patient.

The authors declare about the absence of conflict of interest with respect to this publication. All authors contributed equally to this article.

Mechanisms of Psychiatric Comorbidities in Epilepsy

Psychiatric illnesses, including depression and anxiety, are highly comorbid with epilepsy (for review see Josephson and Jetté (Int Rev Psychiatry 29:409-424, 2017), Salpekar and Mula (Epilepsy Behav 98:293-297, 2019)). Psychiatric comorbidities negatively impact the quality of life of patients (Johnson et al., Epilepsia 45:544-550, 2004; Cramer et al., Epilepsy Behav 4:515-521, 2003) and present a significant challenge to treating patients with epilepsy (Hitiris et al., Epilepsy Res 75:192-196, 2007; Petrovski et al., Neurology 75:1015-1021, 2010; Fazel et al., Lancet 382:1646-1654, 2013) (for review see Kanner (Seizure 49:79-82, 2017)). It has long been acknowledged that there is an association between psychiatric illnesses and epilepsy. Hippocrates, in the fourth-fifth century B.C., considered epilepsy and melancholia to be closely related in which he writes that "melancholics ordinarily become epileptics, and epileptics, melancholics" (Lewis, J Ment Sci 80:1-42, 1934). The Babylonians also recognized the frequency of psychosis in patients with epilepsy (Reynolds and Kinnier Wilson, Epilepsia 49:1488-1490, 2008). Despite the fact that the relationship between psychiatric comorbidities and epilepsy has been recognized for thousands of years, psychiatric illnesses in people with epilepsy still commonly go undiagnosed and untreated (Hermann et al., Epilepsia 41(Suppl 2):S31-S41, 2000) and systematic research in this area is still lacking (Devinsky, Epilepsy Behav 4(Suppl 4):S2-S10, 2003). Thus, although it is clear that these are not new issues, there is a need for improvements in the screening and management of patients with psychiatric comorbidities in epilepsy (Lopez et al., Epilepsy Behav 98:302-305, 2019) and progress is needed to understand the underlying neurobiology contributing to these comorbid conditions. To that end, this chapter will raise awareness regarding the scope of the problem as it relates to comorbid psychiatric illnesses and epilepsy and review our current understanding of the potential mechanisms contributing to these comorbidities, focusing on both basic science and clinical research findings.

The ROME (Retrospective Observational Multicenter study on Eslicarbazepine) study: Efficacy and behavioural effects of Eslicarbazepine acetate as adjunctive therapy for adults with partial onset seizures in real life

PURPOSE

Eslicarbazepine acetate (ESL) is a third-generation member of the dibenzazepine family approved in 2009 by the European Medicines Agency with the indication of adjunctive therapy in adult people with partial-onset seizures (PPOS). We aimed at assessing the ESL impact on seizure frequency and quality of life in PPOS with a particular attention to sleepiness and depression.

METHODS

We evaluated 50 adult PPOS (>18 years; 48 ± 14 years-old; 23 males) treated with adjunctive ESL for ≥2months with a retrospective multi-centric design. Clinical files of the last 2 years were reviewed checking for monthly seizure frequency, treatment retention rate, adverse drug reactions (ADRs), concomitant anti-epileptic drugs and behavioural scales for sleepiness (Stanford Sleepiness Scale, SSS, and Epworth Sleepiness Scale, ESS), depression (Beck Depression Inventory-II, BDI) and overall quality of life (QOLIE-31).

RESULTS

At the end of 96 ± 28 days of ESL treatment, the mean seizure reduction was 56%; 60% of patients had seizure reduction above 50%, with a 31% of the whole population becoming seizure free. We reported 16 ADRs with 4 hyponatremia. Retention rate was 76%. Patient reported less sleepiness after ESL (SSS, p = 0.031; ESS, p = 0.0000002). Before ESL, 38% of patients had pathologic BDI scores, which normalized in most of them (73%) after ESL (BDI improvement, p = 0.000012). These scores resulted in an amelioration of quality of life (QOLIE-31, p = 0.000002).

CONCLUSIONS

ESL is a safe and effective anti-epileptic drug in a real life scenario, with an excellent behavioural profile for the overall quality of life and, in particular, for sleepiness and depression.

Lamotrigine: when and where does it act in affective disorders? A systematic review

Recent published data and treatment guidelines have created uncertainty about the use of lamotrigine in affective disorders, especially in acute bipolar depression. Furthermore, unpublished data on lamotrigine in mania, mixed episodes, unipolar depression and rapid cycling are still waiting to be integrated into the literature. Therefore, we critically reviewed the position of lamotrigine in the acute and long-term treatment of affective disorders. Studies were identified by searching English language articles published in MEDLINE using the key words: lamotrigine, bipolar depression, unipolar depression, mania, mixed episode, long-term treatment, rapid-cycling. Results of unpublished trials were obtained from the GlaxoSmithKline website. Lamotrigine showed efficacy in the prophylaxis of bipolar disorder, more so in depressive than manic episodes. There was no evidence of effectiveness in the acute treatment of mania, mixed episodes, unipolar depression or rapid-cycling bipolar I disorder. Its effect in the acute treatment of bipolar depression is at most small. Based on current evidence, lamotrigine is indicated for the prophylaxis of bipolar disorder with predominantly depressive episodes. Its effectiveness in the acute treatment of bipolar depression is open to debate, and practical considerations limit its usefulness here. There are no grounds for recommending its use in manic or mixed states, in rapidly-cycling bipolar I or in unipolar depression.

The contextual fear conditioning deficit presented by spontaneously hypertensive rats (SHR) is not improved by mood stabilizers

OBJECTIVES

We have recently reported that spontaneously hypertensive rats (SHR) present a contextual fear conditioning (CFC) deficit. This deficit is improved by antipsychotic drugs, potentiated by proschizophrenia manipulations and not altered by acute administration of carbamazepine, lamotrigine and valproic acid. Nevertheless, the effects of lithium-a classical mood stabilizer-or repeated treatment with these drugs were not evaluated. The main aim of the present study was to extend our previous work by investigating a possible beneficial effect of acute and/or chronic treatments with lithium or lamotrigine on the acquisition deficit of CFC presented by SHR.

METHODS

Rats were submitted to CFC task after an acute treatment with lithium and/or a repeated treatment with lithium and lamotrigine.

RESULTS

Our data revealed that the CFC deficit presented by SHR is not improved by acute or repeated treatment with lithium. Repeated lamotrigine treatment potentiated the deficit presented by SHR and impaired CFC in control animals (Wistar Rats).

CONCLUSIONS

These data reinforce the absence of beneficial effects of mood stabilizers on the emotional context processing impairment modeled by SHR.

Genetic predisposition of life-threatening antiepileptic-induced skin reactions

IMPORTANCE OF THE FIELD

Recent advances in pharmacogenetic studies have uncovered increasingly more genes that predispose individuals to adverse drug reactions. Aromatic antiepileptic drugs (AEDs) are a frequent cause of severe cutaneous adverse reactions (SCAR). A strong genetic association between HLA-B*1502 and carbamazepine (CBZ)-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) has been shown in Han Chinese patients.

AREAS COVERED IN THIS REVIEW

This article reviews and updates genetic information associated with CBZ and other AEDs causing SCAR in different ethnic populations.

WHAT THE READER WILL GAIN

Independent studies from different countries confirmed that patients carrying the HLA-B*1502 are at high risk of SJS/TEN when exposed to CBZ. The US FDA and similar regulatory agencies in Canada and Taiwan have updated the CBZ drug label to include the genetic information. Available data also suggest that HLA-B*1502 is a risk allele for SJS/TEN caused by other aromatic AEDs with a similar structure to CBZ.

TAKE HOME MESSAGE

Screening for HLA-B*1502 allele before starting treatment with CBZ is justified in patients from high-risk populations as recommended by regulatory agencies. Similar chemicals should also be avoided in individuals who test positive for HLA-B*1502.

Is anticonvulsant treatment of mania a class effect? Data from randomized clinical trials

Our aim was to evaluate the efficacy and tolerability of anticonvulsant agents for the treatment of acute bipolar mania and ascertain if their effects on mania are a "class" effect. We conducted a systematic review of randomized controlled trials (RCTs) with placebo or active comparator, in acute bipolar mania in order to summarize available data on anticonvulsant treatment of mania/mixed episodes. We searched (PubMed/MEDLINE) with the combination of the words "acute mania" and "clinical trials" with each one of the following words: "anticonvulsants/antiepileptics,""valproic/valproate/divalproex,""carbamazepine,""oxcarbazepine,""lamotrigine,""gabapentin,""topiramate,""phenytoin,""zonisamide,""retigabine,""pregabalin,""tiagabine,""levetiracetam,""licarbazepine,""felbamate," and "vigabatrin." Original articles were found until November 1, 2008. Data from 35 randomized clinical trials suggested that not all anticonvulsants are efficacious for the treatment of acute mania. Valproate showed greater efficacy in reducing manic symptoms, with response rates around 50% compared to a placebo effect of 20-30%. It appears to have a more robust antimanic effect than lithium in rapid cycling and mixed episodes. As valproate, the antimanic effects of carbamazepine have been demonstrated. Evidences did not support the efficacy of the gabapentin, topiramate as well as lamotrigine as monotherapy in acute mania and mixed episodes. Oxcarbazepine data are inconclusive and data regarding other anticonvulsants are not available. Anticonvulsants are not a class when treating mania. While valproate and carbamazepine are significantly more effective than placebo, gabapentin, topiramate, and lamotrigine are not. However, some anticonvulsants may be efficacious in treating some psychiatric comorbidities that are commonly associated to bipolar illness.

Antiepileptic drugs in epilepsy and other disorders--a population-based study of prescriptions

PURPOSE

The aim of the study was to quantify the use of antiepileptic drugs (AEDs) in epilepsy and other indications in a nation-wide population using a prescription database.

MATERIALS AND METHODS

Prescription data of AEDs were collected from the Norwegian Prescription Database for the period 2004-2007, including 5.1 million prescriptions from 144,653 patients, all having at least one prescribed and dispensed AED. Diagnosis-related reimbursement codes were used as indicators for clinical use.

RESULTS

Of the AEDs used, 71% was in epilepsy, 15% in psychiatry, 13% in neuropathic pain, and <1% in migraine, trigeminus neuralgia and cancer adjuvance. The use in epilepsy increased steadily from 7.0 to 7.5 DDDs/1000 inhabitants/day (7%) from 2004 to 2007. The use of AEDs in other indications increased considerably more from 2004 to 2007: Neuropathic pain to 1.40 DDDs/1000 inhabitants/day (360%), psychiatry to 1.59 (200%), and migraine to 0.005 (642%). The prevalence of AED users increased and in 2007 it was 0.97% in epilepsy, 0.8% in neuropathic pain, 0.33% in psychiatry and 0.001% in migraine. In 2007, 49% of the AEDs used in epilepsy were a new drug, carbamazepine, lamotrigine and valproate being most frequently used. New AEDs were used in 96% in migraine prophylaxis, 94% in neuropathic pain, and 64% in psychiatry.

CONCLUSIONS

Based on a nation-wide prescription database, this study quantifies the wide and increasing use of AEDs, in particular the newer drugs.

Patterns of antiepileptic drug overdose differ between men and women: admissions to the Edinburgh Poisons Unit, 2000-2007

BACKGROUND AND AIMS

Antiepileptic drugs are increasingly used in patients with psychiatric disorders who are at increased risk of self-harm. This might increase the likelihood that these agents are used as a means of overdose. This study was designed to examine the rate of occurrence of antiepileptic drug overdose between 2000 and 2007.

METHODS

A retrospective observational study examined patterns of antiepileptic drug overdose in patients admitted to the Edinburgh Poisons Unit, and compared prescription data for the corresponding region. Data were compared using chi-square trend tests.

RESULTS

There were 18 010 admissions to the Toxicology Unit, and 613 patients ingested at least one antiepileptic drug (3.4%). The most frequently implicated were carbamazepine, sodium valproate, phenytoin and lamotrigine, which corresponded with those most commonly prescribed. Women were more likely to ingest lamotrigine than men (P < 0.0001), and less likely to ingest sodium valproate (P = 0.0234). Patients that ingested antiepileptic drugs were more likely to be admitted to hospital for >1 day (22% vs. 8%, P < 0.0001) and need transfer to a psychiatric facility (14% vs. 7%, P < 0.0001).

CONCLUSIONS

Patients that ingested antiepileptic drugs required more intensive medical and psychiatric intervention compared to ingestion of other agents. Significant gender differences were noted in the specific antiepileptic drug ingested. Further work is required to establish whether this discrepancy may be explained by gender-based prescribing practices.

Modifications of Antiepileptic Drugs for Improved Tolerability and Efficacy

Introduction

A large number of antiepileptic drugs (AEDs) are available today, but they may not be satisfactory regarding clinical efficacy, tolerance, toxicity or pharmacokinetic properties. The purpose of this review is to focus upon the rationale behind the chemical modifications of several recently marketed AEDs or drugs in development and to categorize them according to the main purposes for the improvements: better efficacy or tolerability accompanied by improved pharmacokinetic properties.

Material and Method

AEDs that have been chemically modified to new derivatives during the last years are reviewed based on recent publications and PubMed-searches.

Results and Discussion

Improvement in pharmacokinetic parameters may affect both tolerability and efficacy. Modifications to improve tolerability include various valproate analogues, divided into aliphatic amides, cyclic derivatives or amino acid conjugates. Furthermore, there are the carbamazepine analogues oxcarbazepine and eslicarbazepine, the felbamate analogues fluorofelbamate and carisbamate (RWJ 33369), and the lamotrigine analogue JZP-4. The levetiracetam analogues brivaracetam and seletracetam and the derivatives of gabapentin, pregabalin and XP13512, have improved selectivity compared to their parent compounds. Other new drugs have new mechanisms of action related to GABA and glutamate receptors; the glutamate antagonists like topiramate (talampanel and NS-1209), and GABAA receptor agonists, benzodiazepine or progesterone analogues (ELB-139 and ganaxolone).

Conclusion

Further challenges for development of new AEDs include investigations of target molecules affected by pathophysiological processes and detailed structure-activity relationships with focus on stereoselectivity. These potential drugs may become of importance in future drug therapy in epilepsy and other CNS disorders.

Update on the treatment and management of schizophrenia and bipolar disorder

Schizophrenia and bipolar disorder are two debilitating mental health disorders, both of which manifest early in adulthood and are associated with severe impairment as well as increased suicide risk. In addition, factors affecting disease severity, such as substance abuse, are often prevalent in these patient populations. In the United States, the prevalence of bipolar disorder is believed to be approximately 3.5%, while the rate for schizophrenia is approximately 1%. Although each disorder presents with its own symptom profile, the approaches to treatment are similar and include early diagnosis and use of psychosocial therapy. Research initiatives, such as genetic studies, are used in both disorders as well. For schizophrenia, treatment typically includes the combination of an antipsychotic and psychosocial intervention. For bipolar disorder, clinicians commonly prescribe mood-stabilizing drugs (eg, lithium, valproic acid) as first-line treatment. Many of the second-generation antipsychotics have been approved by the US Food and Drug Administration for bipolar disorder treatment in the manic phase. Patients who are affected by either disorder also face the challenges of treatment nonadherence, which can be affected by substance abuse and can hinder symptom remission as well as spur unnecessary medication switches due to nonresponse. Family members play a key role in the treatment of either disorder. This expert review supplement focuses on treatment options and research strategies being utilized for the management and advanced understanding of schizophrenia and bipolar disorder. Research examining the pharmacology of commonly used medications for the treatment of both disorders is also presented.