Treatment of panic disorder and comorbid substance abuse with divalproex sodium

Anticonvulsant and antipsychotic medications in the pharmacotherapy of panic disorder: a structured review

BACKGROUND

As the remission rate of panic disorder (PD) achieved with conventional pharmacotherapy ranges between 20% and 50%, alternative psychopharmacological strategies are needed. We aimed to firstly review data regarding use of antipsychotic and non-benzodiazepine anticonvulsant medication in PD patients with or without comorbidities; secondly, to review data concerning reduction of panic symptoms during treatment of another psychiatric disorder with the same medications; and thirdly, to examine reports of anticonvulsant- or antipsychotic-induced new-onset panic symptomatology.

METHODS

We performed a PubMed search (last day: 28 April 2020) of English-language studies only, combining psychopathological terms (e.g. 'panic disorder') and terms referring either to categories of psychotropic medications (e.g. 'anticonvulsants') or to specific drugs (e.g. 'carbamazepine'). All duplications were eliminated. All studies included in the review met certain inclusion/exclusion criteria. The level of evidence for the efficacy of each drug was defined according to widely accepted criteria.

RESULTS

In treatment-resistant PD, beneficial effects have been reported after treatment (mostly augmentation therapy) with a range of anticonvulsant (carbamazepine, gabapentin, lamotrigine, levetiracetam, oxcarbamazepine, valproate, vigabatrin, tiagabine) and antipsychotic (aripiprazole, olanzapine, risperidone, sulpiride) medications: overall, most medications appear generally well tolerated. Additionally, bipolar patients receiving valproate or quetiapine-XR (but not risperidone or ziprasidone) demonstrated reductions of comorbid panic-related symptoms. There are case reports of new-onset panic symptoms associated with clozapine, haloperidol, olanzapine and topiramate, in patients with conditions other than PD. The small-to-modest sample size, the lack of control groups and the open-label and short-term nature of most of the reviewed studies hinder definitive conclusions regarding either the short-term and long-term efficacy of antipsychotic and anticonvulsant medications or their potential long-term side effects.

CONCLUSION

Some atypical antipsychotic and anticonvulsant medications may have a role in the treatment of some PD patients, mostly when more conventional approaches have not been successful, but the quality of supporting evidence is limited.

Frontoparietal Cortical Thinning in Respiratory-Type Panic Disorder: A Preliminary Report

OBJECTIVE

Many evidences raise the possibility that the panic disorder (PD) patients with respiratory subtype (RS) may have characteristic structural abnormalities. We aimed to explore the structural differences between PD patients with and without the respiratory symptoms.

METHODS

Patients with PD were recruited from the Department of Psychiatry at Korea University Anam Hospital. Respiratory subtype (RS) was diagnosed when at least 4 out of 5 of the following respiratory symptoms were present during the panic attack: fear of dying, chest pain/discomfort, shortness of breath, paresthesias, and a choking sensation. We acquired high-resolution MRI scans and used FreeSurfer to obtain a measure of cortical thickness for each patient.

RESULTS

Cluster based analysis revealed significantly decreased cortical thickness in the left hemisphere in the caudal-middle-frontal, superior frontal, and posterior parietal areas in the RS group. No significant difference was observed in any of the limbic areas.

CONCLUSION

Respiratory symptoms of panic disorder were associated with a reduction in cortical thickness in the left frontal and parietal areas. This finding leads to the assumption that the frontoparietal network is the crucial component in a larger cortical network underlying the perception of dyspnea in RS.

Decreased gray matter volume of the medial orbitofrontal cortex in panic disorder with agoraphobia: a preliminary study

BACKGROUND

Patients with panic disorder with agoraphobia (PDA) have clinical symptoms such as the fear of being outside or of open spaces from which escape would be difficult. Although recent neurobiological studies have suggested that fear conditioning and extinction are associated with PDA, no study has examined the possible structural abnormalities in patients with PDA.

METHODS

This preliminary study compares the gray matter volume among patients with PDA, those with panic disorder without agoraphobia (PDW), and healthy controls (HC) using high-resolution 3.0 T magnetic resonance imaging (MRI) with voxel-based morphometry (VBM).

RESULTS

Compared with HC, patients with PDA showed decreased gray matter volume in their left medial orbitofrontal gyrus. However, differences were not found in the gray matter volumes of patients with PDW and whole panic disorder compared with HC.

CONCLUSIONS

These findings suggest that the phobic avoidance found in patients with PDA arise from abnormalities in the medial orbitofrontal cortex, which plays an important role in fear extinction. Future studies should investigate the neuroanatomical substrates of PDA and distinguish them from those of PDW.

Mood stabilizers in the treatment of substance use disorders

Individuals suffering from drug addiction may also manifest features of bipolar spectrum disorders. Hyperthymic and cyclothymic temperaments may render individuals vulnerable to later development of substance abuse. Bipolar disorders themselves may be altered or precipitated by substance use, most notably by stimulants (amphetamines), alcohol, and cannabinoids. The clinical usefulness of mood stabilizers, particularly antiepileptics, has been established as safe and effective in substance abusers with and without comorbid mood disorders. Most studies on this issue have been of short duration and focused on the resolution of a currently manifest period of illness. Few studies have been conducted on the usefulness of these drugs on the long-term longitudinal course of these diseases, such as frequently encountered recurrent relapses into states of agitation, impulsivity, and/or dissatisfaction. As opposed to the clinical experience with traditional antidepressants and neuroleptics, antiepileptics do not induce counter-polar states (depressed patients abruptly turning manic or hypomanic; nor patients currently hypomanic or manic turning abruptly depressed). Many clinicians consider antiepileptic mood stabilizers to be the preferred category of medications for the treatment of such patients. Valproate appears to be a potentially fruitful medication to study in these dual diagnosis patients due to preliminary evidence demonstrating its anticraving efficacy.

Management of co-morbid anxiety and alcohol disorders: parallel treatment of disorders

Co-morbid alcohol-related disorders and anxiety disorders have been found to occur in alcohol treatment populations, anxiety treatment populations and the general community. People suffering from co-occurring alcohol-related and anxiety disorders are more prone to relapse to alcohol abuse, and more likely to re-enter the treatment system for either disorder than sufferers of either disorder without a co-morbid disorder. To review the current state of the management of this disorder, evidence of the prevalence of this co-morbid condition in clinical and community populations is examined, then the theoretical mechanisms that might explain this connection are reviewed. A comparison of the few treatment studies of co-morbid alcohol and anxiety disorders shows a limited number of pharmacological treatment trials and no psychotherapy outcome trials. This review shows that it is no longer sustainable to conceptualize co-morbidity of alcohol and anxiety disorders as a unitary concept, i.e. lumping alcohol-related and anxiety disorders as one global condition, but as separate distinct combinations of particular anxiety disorders, e.g. alcohol dependence and panic disorder, alcohol dependence and generalize anxiety disorder. The recommended treatment approach, supported by the evidence, is to offer separate and parallel therapy for the alcohol-related and anxiety disorder, until empirical evidence from treatment outcome studies suggest otherwise. There is an urgent need to conduct treatment outcome research for the subtypes of co-morbid alcohol and anxiety disorders.

The role of anticonvulsant drugs in anxiety disorders: a critical review of the evidence

Antiepileptic drugs (AEDs) have been successfully used in the treatment of mood disturbances, leading clinicians and researchers to investigate their use in other psychiatric disorders. This article reviews the literature about the potential efficacy of AEDs in anxiety disorders. An updated MEDLINE search (January 1970 to September 2006) using the terms "panic disorder," "agoraphobia," "posttraumatic stress disorder," "obsessive-compulsive disorder," "generalized anxiety disorder," "social phobia," "phobia," "carbamazepine," "phenobarbital," "phenytoin," "valproate," "lamotrigine," "topiramate," "vigabatrin," "tiagabine," "gabapentin," "levetiracetam," and "pregabalin" showed more than 70 articles and 38 published studies. Only articles published in English were reviewed. We have assigned level 1 of evidence to meta-analysis and replicated randomized controlled trials, level 2 to at least 1 randomized controlled trial, level 3 to uncontrolled trials with 10 or more subjects, and level 4 to anecdotal case reports. The strongest evidence has been demonstrated for pregabalin in social phobia and generalized anxiety disorder, lamotrigine in posttraumatic stress disorder, and gabapentin in social anxiety. The available data about gabapentin in panic disorder are somewhat mixed, and more definitive conclusion would require additional studies. This review suggests that AEDs can be an alternative treatment in some anxiety disorders. Further investigation is needed to determine in what circumstances they should be used in individuals who are partially responsive or nonresponsive to conventional therapy.