Risperidone augmentation of paroxetine in a case of severe, treatment-refractory obsessive-compulsive disorder without comorbid psychopathology

Characterization of Behavioral Phenotypes in Heterozygous DAT Rat Based on Pedigree

Dopamine is an essential neurotransmitter whose key roles include movement control, pleasure and reward, attentional and cognitive skills, and regulation of the sleep/wake cycle. Reuptake is carried out by the dopamine transporter (DAT; DAT1 SLC6A3 gene). In order to study the effects of hyper-dopaminergia syndrome, the gene was silenced in rats. DAT-KO rats show stereotypical behavior, hyperactivity, a deficit in working memory, and an altered circadian cycle. In addition to KO rats, heterozygous (DAT-HET) rats show relative hypofunction of DAT; exact phenotypic effects are still unknown and may depend on whether the sire or the dam was KO. Our goal was to elucidate the potential importance of the parental origin of the healthy or silenced allele and its impact across generations, along with the potential variations in maternal care. We thus generated specular lines to study the effects of (grand) parental roles in inheriting the wild or mutated allele. MAT-HETs are the progeny of a KO sire and a WT dam; by breeding MAT-HET males and KO females, we obtained subjects with a DAT -/- epigenotype, named QULL, to reflect additional epigenetic DAT modulation when embryos develop within a hyper-dopaminergic KO uterus. We aimed to verify if any behavioral anomaly was introduced by a QULL (instead of KO) rat acting as a direct father or indirect maternal grandfather (or both). We thus followed epigenotypes obtained after three generations and observed actual effects on impaired maternal care of the offspring (based on pedigree). In particular, offspring of MAT-HET-dam × QULL-sire breeding showed a compulsive and obsessive phenotype. Although the experimental groups were all heterozygous, the impact of having a sire of epigenotype QULL (who developed in the uterus of a KO grand-dam) has emerged clearly. Along the generations, the effects of the DAT epigenotype on the obsessive/compulsive phenotype do vary as a function of the uterine impact on either allele in one's genealogical line.

Critical Review of the Use of Second-Generation Antipsychotics in Obsessive-Compulsive and Related Disorders

Currently, all second-generation antipsychotics are approved for schizophrenia. Many are also approved for bipolar disorder, with some also approved as adjunctive treatment for depression and autism-related irritability. Second-generation antipsychotics are increasingly being prescribed for indications other than those approved by the Food and Drug Administration, such as in dementia, anxiety, and post-traumatic stress disorder to name a few. Obsessive-compulsive and related disorders are a group of disorders characterized by preoccupation and repetitive behaviors. According to the latest edition of the Diagnostic and Statistical Manual of Mental Disorders, obsessive-compulsive disorder, body dysmorphic disorder, trichotillomania, hoarding disorder, and excoriation, the latter two being newly designated disorders, fall under obsessive-compulsive and related disorders. Due to a lack of well designed clinical studies specifically addressing the use of second-generation antipsychotics in obsessive-compulsive and related disorders, it is unknown whether these agents are clinically beneficial. Current research describing the pathophysiology of these disorders shows the involvement of similar brain regions and neurotransmitters across the five obsessive-compulsive and related disorders. Despite differences in the receptor binding profiles, second-generation antipsychotics share many common pharmacodynamics properties. This review sought to examine all the published reports of second-generation antipsychotics being used in the management of symptoms of the aforementioned diseases and compile evidence for clinicians who encounter patients who are unresponsive to standard treatment.

Neuroimaging in anxiety disorders

Neuroimaging studies have gained increasing importance in validating neurobiological network hypotheses for anxiety disorders. Functional imaging procedures and radioligand binding studies in healthy subjects and in patients with anxiety disorders provide growing evidence of the existence of a complex anxiety network, including limbic, brainstem, temporal, and prefrontal cortical regions. Obviously, "normal anxiety" does not equal "pathological anxiety" although many phenomena are evident in healthy subjects, however to a lower extent. Differential effects of distinct brain regions and lateralization phenomena in different anxiety disorders are mentioned. An overview of neuroimaging investigations in anxiety disorders is given after a brief summary of results from healthy volunteers. Concluding implications for future research are made by the authors.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of anxiety, obsessive-compulsive and post-traumatic stress disorders - first revision

In this report, which is an update of a guideline published in 2002 (Bandelow et al. 2002, World J Biol Psychiatry 3:171), recommendations for the pharmacological treatment of anxiety disorder, obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD) are presented. Since the publication of the first version of this guideline, a substantial number of new randomized controlled studies of anxiolytics have been published. In particular, more relapse prevention studies are now available that show sustained efficacy of anxiolytic drugs. The recommendations, developed by the World Federation of Societies of Biological Psychiatry (WFSBP) Task Force for the Pharmacological Treatment of Anxiety, Obsessive-Compulsive and Post-traumatic Stress Disorders, a consensus panel of 30 international experts, are now based on 510 published randomized, placebo- or comparator-controlled clinical studies (RCTs) and 130 open studies and case reports. First-line treatments for these disorders are selective serotonin reuptake inhibitors (SSRIs), serotonin-noradrenaline reuptake inhibitors (SNRIs) and the calcium channel modulator pregabalin. Tricyclic antidepressants (TCAs) are equally effective for some disorders, but many are less well tolerated than the SSRIs/SNRIs. In treatment-resistant cases, benzodiazepines may be used when the patient does not have a history of substance abuse disorders. Potential treatment options for patients unresponsive to standard treatments are described in this overview. Although these guidelines focus on medications, non-pharmacological were also considered. Cognitive behavioural therapy (CBT) and other variants of behaviour therapy have been sufficiently investigated in controlled studies in patients with anxiety disorders, OCD, and PTSD to support them being recommended either alone or in combination with the above medicines.

Dopamine transporter density in the basal ganglia in obsessive-compulsive disorder, measured with [123I]IPT SPECT before and after treatment with serotonin reuptake inhibitors

It has been suggested that dopamine as well as serotonin are associated with the pathophysiology of obsessive-compulsive disorder (OCD). 5-Hydroxytryptophan inhibits dopamine release in healthy persons as well as in patients with OCD, and serotonin tonic inhibition affects dopamine function in basal ganglia, indicating a close relationship between serotonin and the dopamine system. Using iodine-123-labeled N-(3-iodopropen-2-yl)-2 beta-carbomethoxy-3beta-(4-chlorophenyl) tropane ([(123)I]IPT) single photon emission computed tomography (SPECT), we investigated the dopamine transporter (DAT) density in the basal ganglia of patients with OCD. The test consists of two measurements before and after treatment with serotonin reuptake inhibitors (SRIs). Ten patients with OCD before and after treatment with SRIs were included. We performed brain SPECT 2 h after intravenous administration of [(123)I]IPT using a dual-head SPECT camera (Vertex, ADAC, Calif., USA) and analyzed the SPECT data, reconstructed for the assessment of the specific/nonspecific DAT binding ratio in the basal ganglia. We then examined the correlation between the scores of OCD symptom changes, assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), and DAT binding ratio. Patients with OCD after treatment with SRIs showed a significantly decreased DAT binding ratio in the right basal ganglia compared with baseline. A significant correlation was found between the total scores and compulsion score changes of the Y-BOCS and the changes of the DAT binding ratio of the right basal ganglia. These findings suggest that the dopaminergic neurotransmitter system of the basal ganglia could play an important role in the symptom improvement of OCD patients.

Novel uses for risperidone: focus on depressive, anxiety and behavioral disorders

Risperidone has been shown to be a safe and effective atypical antipsychotic agent. It was initially approved for the treatment of schizophrenia, and now, in many countries, is used to treat other conditions, including bipolar disorder, dementia and behavior problems in a range of age groups. Yet, frequent off-label use by clinicians to treat other mood and anxiety disorders and behavioral disorders is common and requires an examination of the risks and benefits in such populations. A review of the literature provides varying levels of evidence supporting its use in a range of depressive and anxiety disorders, and in special populations, including children and the elderly. Most reports are based on short-term studies and include its use both as monotherapy and as an augmenting agent to other psychotropics, and in a range of doses. Further randomized controlled trials are needed to confirm the efficacy and tolerability of risperidone, both short- and long-term, in many of these conditions. The published evidence is summarized, with recommendations and suggestions for its use.

The genetic studies of obsessive-compulsive disorder and its future directions

Obsessive-compulsive disorder (OCD) is characterized by recurrent and persistent thoughts (obsessions), and repetitive behaviors or mental acts (compulsions). In Korea, an epidemiological study reported that the lifetime prevalence of OCD in the population was greater than two percent. The exact cause of OCD is still unknown. Evidence from familial, twin and segregation studies supports the role of a genetic component in the etiology of OCD. In addition, there is growing evidence that OCD has a specific neurochemical and neuroanatomical basis. According to this evidence, researchers have selected various candidate genes which have been implicated in the neurophysiology of OCD, and differences of allelic variants in OCD patients and controls have been analyzed. In this review we will introduce the results of previous genetic studies of OCD which have been performed in other populations, including twin studies, family studies, segregation analyses, linkage analyses, and association studies. In addition to these studies, we will present the results of our genetic studies of OCD performed in Korea.

Olanzapine augmentation of fluoxetine for refractory generalized anxiety disorder: a placebo controlled study

BACKGROUND

There has been little systematic study of "next-step" interventions for patients with generalized anxiety disorder (GAD) who remain symptomatic despite initial pharmacotherapy. We present one of the first randomized controlled trials for refractory GAD, comprising double blind augmentation with olanzapine or placebo for patients remaining symptomatic on fluoxetine.

METHODS

Patients remaining symptomatic after 6 weeks of fluoxetine (20 mg/day) were randomized to 6 weeks of olanzapine (mean dose 8.7 +/- 7.1 mg/day) or placebo augmentation.

RESULTS

Twenty-four of 46 fluoxetine-treated patients were randomized. Olanzapine resulted in a greater proportion of treatment responders based on a Clinical Global Impression-Severity Scale (CGI-S) end point score of 1 or 2 (Fisher's exact test [FET] p < .05) or a 50% reduction in Hamilton Anxiety Scale (HAMA-A) score (FET p < .05). There were no other statistically significant differences for olanzapine compared with placebo augmentation in outcome measures, though rates of remission (HAM-A <or= 7) on olanzapine were higher at the level of a trend (FET, p = .1). Average weight gain for completers was greater with olanzapine than placebo augmentation (11.0 +/- 5.1 vs. -0.7 +/- 2.4 pounds: t = 6.32, p < .001).

CONCLUSIONS

Olanzapine may have a salutary effect on anxiety for some GAD patients remaining symptomatic despite initial serotonin selective reuptake inhibitor (SSRI) therapy, but the emergence of significant weight gain represents an important clinical consideration.

Pharmacological augmentation strategies for treatment-resistant obsessive-compulsive disorder

First-line treatment for obsessive-compulsive disorder (OCD) has been well-established for over a decade, although newer medications, such as citalopram and venlafaxine, have emerged to take a place among the older, more established serotonin re-uptake inhibitors (SRIs). Unfortunately, as many as 50% of all patients with OCD will have symptoms refractory to a single medication treatment trial, and a smaller percentage will remain refractory after two or more trials. The optimal dosage and duration for first-line trials have been established. Many strategies exist for patients who do not respond to first- or second-line medication trials, including behavioural therapy, switching to newer SRIs, and augmentation with additional medications. This review will focus on medication strategies for augmenting SRI treatment response in OCD treatment, including neuroleptic and serotonergic agents. Future investigations should include more controlled studies and investigate medications that are less likely to trigger extrapyramidal symptoms, diabetes mellitus and weight gain.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of anxiety, obsessive-compulsive and posttraumatic stress disorders

In this report, recommendations for the pharmacological treatment of anxiety and obsessive-compulsive disorders are presented, based on available randomized, placebo- or comparator-controlled clinical studies. Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for panic disorder. Tri2-cyclic antidepressants (TCAs) are equally effective, but they are less well tolerated than the SSRIs. In treatment-resistant cases, benzodiazepines like alprazolam may be used when the patient does not have a history of dependency and tolerance. Due to possible serious side effects and interactions with other drugs and food components, the irreversible monamine oxidase inhibitor (MAOI) phenelzine should be used only when first-line drugs have failed. In generalised anxiety disorder, venlafaxine and SSRIs can be recommended, while buspirone and imipramine may be alternatives. For social phobia, SSRIs are recommended for the first line, and MAOIs, moclobemide and benzodiazepines as second line. Obsessive-compulsive disorder is best treated with SSRIs or clomipramine.

Severe weight gain induced by combination treatment with risperidone and paroxetine

Successful combination therapy with atypical antipsychotics and selective serotonin reuptake inhibitors has been reported for several psychiatric conditions. However, great attention should be paid to the possible adverse effects. In this retrospective chart review, we focused on the drug-drug interaction of paroxetine and risperidone. Retrospectively, we identified two patients treated with a combination of risperidone and paroxetine therapy, and analyzed their medical records. During a 3-month period of monotherapy with risperidone, the changes in body weight were +/- 0.0 kg in Patient 1 and -2.0 kg in Patient 2. In contrast, during combination therapy with paroxetine and risperidone, the body-weight changes were +14.0 kg in Patient 1 (after 4 months) and +13.5 kg in Patient 2 (after 5 months). In addition, diabetes mellitus was observed in Patient 2. Regarding the mechanism of severe weight gain in these two patients, we speculate a drug-drug interaction involving inhibition of the cytochrome P450 enzyme 2D6 (CYP4502D6) by paroxetine.

Does risperidone have a place in the treatment of nonschizophrenic patients?

There is a now a substantial body of evidence that suggests the new antipsychotic agent, risperidone, may be safe and effective for treating psychotic, affective or behavioural symptoms associated with various disorders other than schizophrenia, schizophreniform disorder or schizo-affective disorder. These conditions include bipolar disorder, obsessive-compulsive disorder, Tourette's syndrome, dementia, Lewy body disease, mental retardation, Parkinson's disease, idiopathic segmental dystonia and organic catatonia. Although much of the data is anecdotal or in the form of open studies, there is now emerging a small number of well controlled investigations supporting efficacy for mania, dementia, behavioural disturbance in mental retardation and conduct disorder. Conventional antipsychotics have long been used, either in a primary capacity or as an adjunct to treat these disorders; however, they have limited benefit, pose significant risks of extrapyramidal side-effects, and may cause the potentially life-threatening neuroleptic malignant syndrome. In contrast, risperidone at the recommended low doses may be efficacious and pose reduced risk of motor side-effects. This article reviews the evidence that risperidone may be an effective new treatment for disorders other than schizophrenia.

Reciprocal autoreceptor and heteroreceptor control of serotonergic, dopaminergic and noradrenergic transmission in the frontal cortex: relevance to the actions of antidepressant agents

The frontal cortex (FCX) plays a key role in processes that control mood, cognition and motor behaviour, functions which are compromised in depression, schizophrenia and other psychiatric disorders. In this regard, there is considerable evidence that a perturbation of monoaminergic input to the FCX is involved in the pathogenesis of these states. Correspondingly, the modulation of monoaminergic transmission in the FCX and other corticolimbic structures plays an important role in the actions of antipsychotic and antidepressant agents. In order to further understand the significance of monoaminergic systems in psychiatric disorders and their treatment, it is essential to characterize mechanisms underlying their modulation. Within this framework, the present commentary focuses on our electrophysiological and dialysis analyses of the complex and reciprocal pattern of auto- and heteroreceptor mediated control of dopaminergic, noradrenergic and serotonergic transmission in the FCX. The delineation of such interactions provides a framework for an interpretation of the influence of diverse classes of antidepressant agent upon extracellular levels of dopamine, noradrenaline and serotonin in FCX. Moreover, it also generates important insights into strategies for the potential improvement in the therapeutic profiles of antidepressant agents.