Increased frequency of psychosis after second-generation antiepileptic drug administration in adults with focal epilepsy

Epilepsy and psychosis

Psychotic disorders are eight times more frequent in epilepsy than in the general population. The various clinical syndromes are classified according to their chronology of onset in relation to epileptic seizures: ictal psychoses (during epileptic discharge), post-ictal psychoses (PIP, after a seizure), interictal psychoses (IIP, with no chronological link) and those related to complete seizure control. Antiepileptic drugs can cause psychotic disorders in all these situations. Post-ictal psychoses (PIP) are affective psychoses that occur after a lucid interval lasting 12 to 120hours following a cluster of seizures. They last an average of 10days, with an abrupt beginning and end. PIP are directly linked to epileptic seizures, and disappear when the epilepsy is controlled. Interictal psychoses are schizophrenias. The management of psychotic disorders in epilepsy is neuropsychiatric, and requires close collaboration between epileptologists and psychiatrists. Antipsychotics can be prescribed in persons with epilepsy. Even today, psychotic disorders in epilepsy are poorly understood, under-diagnosed and under-treated.

Psychoses after an antiepileptic drug administration: Frequency, timing, and duration

OBJECTIVES

To clarify the pathophysiology of psychoses after the new administration of antiepileptic drugs (AED), we analyzed the annual incidence, timing of development, and duration of episodes.

METHODS

Psychotic outcomes in the first 6-month period after an AED or non-AED administration in patients with focal epilepsy were exhaustively reviewed in eight Japanese neuropsychiatry institutions. In cases with psychotic episodes, the subtype of psychosis, timing of development, previous history of psychosis, and duration of the episode were evaluated.

RESULTS

Between 1981 and 2015, 5018 new drugs (4402 AED and 616 non-AED) were administered to 2067 patients with focal epilepsy. In the first 6-month period, 105 psychotic episodes occurred (81 interictal psychosis [IIP] and 24 postictal psychosis). Furthermore, 55 cases were first episodes and 50 were recurrent episodes. The frequency of psychoses is significantly higher after AED administration (n = 102) compared with non-AED administration (n = 3). Psychosis occurred most frequently in the initial 1-month period after new-AED administration and tended to decrease with increasing time. The estimated annual incidence of all psychoses after a new AED administration was 3.5% (2.0% for first-episode psychosis and 1.8% for first-episode IIP). Duration of psychoses (mean, 38.5 weeks) was equivalent to overall IIP. Duration of IIP did not shorten with discontinuation of newly administered AED.

SIGNIFICANCE

Patients with epilepsy exhibit psychosis more frequently after new AED administration than after non-AED administration. This study shows the pathophysiology of psychoses after AED administration with annual incidence, the timing of development, and the duration of PAP, which have rarely been reported.

Optimization of Therapy in Patients with Epilepsy and Psychiatric Comorbidities: Key Points

Psychiatric disorder comorbidity in patients with epilepsy (PWE) is very frequent with a mean percentage prevalence of up to 50% and even higher. Such a high frequency suggests that epilepsy and psychiatric disorders might share common pathological pathways. Various aspects contribute in making the matter very complex from a therapeutic point of view. Some antiseizure medications (ASMs), namely valproic acid, carbamazepine, and lamotrigine, have mood-stabilising effects and are routinely used for the treatment of bipolar disorder in patients who do not have epilepsy. Pregabalin and, to a lesser extent, gabapentin, exerts anxiolytic effects. However, several ASMs, in particular levetiracetam, topiramate, and perampanel, may contribute to psychiatric disorders, including depression, aggressive behaviour, and even psychosis. If these ASMs are prescribed, the patient should be monitored closely. A careful selection should be made also with psychotropic drugs. Although most of these can be safely used at therapeutic doses, bupropion, some tricyclic antidepressants, maprotiline, and clozapine may alter seizure threshold and facilitate epileptic seizures. Interactions between ASMs and psychotropic medication may make it difficult to predict individual response. Pharmacokinetic interactions can be assessed with drug monitoring and are consequently much better documented than pharmacodynamic interactions. Another aspect that needs a careful evaluation is patient adherence to treatment. Prevalence of non-adherence in PWE and psychiatric comorbidities is reported to reach values even higher than 70%. A careful evaluation of all these aspects contributes in optimizing therapy with a positive impact on seizure control, psychiatric wellbeing, and quality of life.

Bidirectionality of antiseizure and antipsychotic treatment: A population-based study

PURPOSE

To study the prevalence and directionality of comorbid epilepsy and psychosis in Norway.

METHODS

The Norwegian Prescription Database (NorPD) provided individual-based information on all antiseizure medications (ASMs) and antipsychotic drugs (APDs) dispensed during 2004-2017. Subjects were ≥18 years of age at the end of the study period. Diagnosis-specific reimbursement codes from the 10th revision of the International Classification of Diseases/2nd edition of the International Classification of Primary Care (ICD-10/ICPC-2) combined with ATC codes were used as indicators of diagnosis. Subjects had collected ASMs for epilepsy or APDs for psychosis at least four times, at least once issued with an ICD-10 code from the specialist healthcare service. Directionality was analyzed in subjects receiving both treatments. To reduce prevalent comorbidity bias, we employed a four-year comorbidity-free period (2004-2007). The use of specific ASMs and APDs was analyzed.

RESULTS

A total of 31,289 subjects had collected an ASM for epilepsy at least four times, 28,889 an APD for psychosis. Both the prevalence of treatment for epilepsy and of treatment for psychosis was 0.8%. Further, 891 subjects had been treated for both conditions; 2.8% with epilepsy had been treated for psychosis, and 3.1% with psychosis had been treated for epilepsy. Among 558 subjects included in the analyses of directionality, 56% had collected the first APD before an ASM, whereas 41% had collected an ASM first. During the last year prior to comorbidity onset, levetiracetam, topiramate, or zonisamide had been used for epilepsy by approximately 40%, whereas olanzapine and quetiapine were most used in patients with psychosis, and clozapine in 13%.

CONCLUSION

The proportion of patients with prior antipsychotic treatment at onset of epilepsy is higher than previously acknowledged, as demonstrated in this nation-wide study. Apart from a shared neurobiological susceptibility, the bidirectionality of epilepsy and psychosis may be influenced by various environmental factors, including the interaction of pharmacodynamic effects. APDs may facilitate seizures; ASMs may induce psychiatric symptoms. In patients with combined treatment, these potential drug effects should receive ample attention, along with the psychosocial consequences of the disorders. A prudent multi-professional approach is required.

Epilepsy in patients with schizophrenia: Pathophysiology and basic treatments

Schizophrenia is a chronic psychiatric disorder that may lead to epilepsy. However, there are limited findings on the issues. This narrative review aimed to provide a practical perspective on epilepsy in patients with schizophrenia using the current treatment systems for epilepsy. While there has been a debate on the relationship between epilepsy and schizophrenia, i.e., antagonism, affinity, and coincidence, recent large cohort studies have revealed a high frequency of epilepsy in patients with schizophrenia (4-5 times higher than that of general population). The high incidence observed is likely to be due to the bidirectionality between epilepsy and schizophrenia and additional schizophrenia-related conditions, e.g., antipsychotic drugs (APD), substance abuse, and head injury. As for symptomatology of epilepsy, only one small-size study showed that seizures of patients with schizophrenia are equivalent to those of patients without schizophrenia. Patients with schizophrenia exhibit the first seizure in their twenties or later, which are mostly focal seizures. Most of seizures in patients with schizophrenia can be controlled with conventional antiepileptic drugs. Few patients with schizophrenia develop treatment-resistant epilepsy. However, since drug interactions can be more complicated due to multiple conditions, such as pre-existing polypharmacy, heavy smoking, irregular eating, and comorbid metabolic disorders, cautious monitoring for clinical symptoms is required. To improve seizure control and adherence, non-pharmacological approaches are also recommended. Thus far, for seizure treatments in patients with schizophrenia, we have to use many empirical findings or substitute certain findings from population without schizophrenia because evidence is insufficient. The accumulation of clinical findings may contribute to the development of efficient treatment systems.

Individual vulnerabilities to psychosis after antiepileptic drug administration

Background

Psychosis often develops after the administration of antiepileptic drugs (AEDs) in patients with epilepsy. However, the individual vulnerability and clinical condition of such patients have been rarely scrutinised. We investigated the effect of individually consistent (trait-dependent) and inconsistent (state-dependent) characteristics.

Methods

The individual characteristics, clinical states and psychotic outcome of patients from eight adult epilepsy clinics were retrospectively reviewed over 6-month periods after a new drug (AED or non-AED) administration between 1981 and 2015.

Results

A total of 5018 new drugs (4402 AEDs and 616 non-AEDs) were used in 2015 patients with focal epilepsy. Subsequently, 105 psychotic episodes (81 interictal and 24 postictal) occurred in 89 patients. Twelve patients exhibited multiple episodes after different AED administrations. Trait-dependent characteristics (early onset of epilepsy, known presumed causes of epilepsy, lower intellectual function and a family history of psychosis) were significantly associated with the patients who exhibited psychosis. Absence of family history of epilepsy was also associated with psychosis but not significantly. Subsequent logistic regression analysis with a model incorporating family history of psychosis and epilepsy, and intellectual function was the most appropriate (p=0.000). State-dependent characteristics, including previous psychotic history and epilepsy-related variables (longer duration of epilepsy, AED administration, higher seizure frequency and concomitant use of AEDs) were significantly associated with psychotic episodes. Subsequent analysis found that a model including AED administration and previous psychotic history was the most appropriate (p=0.000).

Conclusion

Psychosis occurring after new AED administration was related to the individual vulnerability to psychosis and intractability of epilepsy.

Herbal Medicine in the Treatment of Epilepsy

Epilepsy is one of the most common disorders of the central nervous system. Although epilepsy is common worldwide, approximately 80% of epileptic patients live in the developing countries or those with low-middle income. Up until the second decade of the 20th century, epilepsy was treated mostly by traditional remedies. Today, antiepileptic drugs are used as a general treatment instead to prevent and control epileptic seizures. However, patient access to these drugs is hindered due to the healthcare systems of their countries and a number of other reasons, such as cultural, socio-demographic, and financial poverty. In addition, approximately 30-40%of epileptic patients suffer from refractory epilepsy, additionally, AEDs have adverse side-effects that can lead to treatment failure or reduce the patient's quality of life. Despite recent advances in the treatment of epilepsy, there is still a need for improving medical treatment with a particular focus on efficacy, safety, and accessibility. Since herbal medicines have been used for many centuries around the world for treating epilepsy, it is, therefore, plausible that a rigorous study on herbal medicine and phytochemical components within plants of various species and origin may lead to the discovery of novel AEDs. Nowadays, many medicinal plants used in different cultures and regions of the world have been identified. Most phytochemical components of these plants have been identified and, in some cases, their targets located. Therefore, it is possible that new, effective, and accessible anticonvulsants drugs can be obtained from a medicinal plant.

[Interictal psychosis of epilepsy]

Interictal psychosis (IIP) refers to psychosis that occurs in clear consciousness in persons with epilepsy (PWE) with temporal onset not during or immediately following a seizure. The pooled prevalence estimate of psychosis in PWE is 5.6%. PWE and schizophrenia have very high mortality, and more than one in four persons with both disorders die between the age of 25 and 50years. IIP can manifest in brief or chronic forms. The chronic forms of IIP may closely resemble schizophrenia. However, some authors have described the typical presence of persecutory and religious delusions, sudden mood swings and the preservation of affect, as well as rarity of negative symptoms and catatonic states, but these differences remain controversial. Typically, IIP starts after many years of active temporal lobe epilepsy. Several epilepsy-related variables are considered pathogenically relevant in IIP including epilepsy type and seizure characteristics. Risk factors for developing IIP are family history of psychosis, learning disability, early age of onset of epilepsy, unilateral or bilateral hippocampal sclerosis, history of status epilepticus, history of febrile seizures, and poorly controlled temporal lobe epilepsy. In patients with epilepsy and psychosis, structural imaging studies have shown several relevant changes leading to conflicting findings. Altered neuronal plasticity and excitability have been described in epilepsy and psychotic disorders. Neuropathological data suggest that IIP are not the result of classic epileptic pathology of the temporal lobe. Forced normalization (FN) and alternating psychosis refer to patients with poorly controlled epilepsy (focal or generalized) who have had psychotic episodes associated with remission of their seizures and disappearance of epileptiform activity on their EEGs. FN mainly occurs in temporal lobe epilepsy when patients have frequent seizures that are abruptly terminated triggered by an antiepileptic drug, vagus nerve stimulation or epilepsy surgery. Treatment is based on withdrawal of the responsible drug, and by transient use of antipsychotics for acute symptomatic control on a case-by-case basis. FN is an entity whose pathophysiology remains uncertain. Antiepileptic drugs (AEDs) may sometimes induce psychotic symptoms and psychosis could be a direct effect of the AEDs. IIP has been reported more frequently following the initiation of zonisamide, topiramate, and levetiracetam when compared with other antiepileptic drugs. However, AEDs do not appear to be the only determinant of IIP. The management of IIP requires a multidisciplinary approach with early involvement of a liaison psychiatrist associated with a neurologist. IIP are underdiagnosed and mistreated. Existing recommendations are extrapolated from those established for the treatment of schizophrenia with some additional guidance from expert opinions. A two-step procedure, not necessarily consecutive, is suggested. The first step requires reevaluation of the antiepileptic treatment. The second step requires initiation of atypical neuroleptics. Antipsychotic drugs should be selected with consideration of the balance between pharmacological profiles, efficacy, and adverse effects. Regarding pharmacokinetic interactions, AEDs with inducing properties reduce the blood levels of all antipsychotics. It is important to consider implications of combining neuroleptics and AEDs with a similar spectrum of side effects. Regarding the duration of treatment, IIP episodes are more likely to be recurrent than in primary schizophrenia. In practice, atypical neuroleptics with few motor side effects such as risperidone can be used as first choice, given the low propensity for drug-drug interactions and the low seizure risk, with the added suggestion to start low and go slow. Clozapine could be prescribed in selected cases.