Intravenous clomipramine challenge in obsessive-compulsive disorder: predicting response to oral therapy at eight weeks

Hypothalamic-pituitary-adrenocortical axis: neuropsychiatric aspects

Evidence of aberrant hypothalamic-pituitary-adrenocortical (HPA) activity in many psychiatric disorders, although not universal, has sparked long-standing interest in HPA hormones as biomarkers of disease or treatment response. HPA activity may be chronically elevated in melancholic depression, panic disorder, obsessive-compulsive disorder, and schizophrenia. The HPA axis may be more reactive to stress in social anxiety disorder and autism spectrum disorders. In contrast, HPA activity is more likely to be low in PTSD and atypical depression. Antidepressants are widely considered to inhibit HPA activity, although inhibition is not unanimously reported in the literature. There is evidence, also uneven, that the mood stabilizers lithium and carbamazepine have the potential to augment HPA measures, while benzodiazepines, atypical antipsychotics, and to some extent, typical antipsychotics have the potential to inhibit HPA activity. Currently, the most reliable use of HPA measures in most disorders is to predict the likelihood of relapse, although changes in HPA activity have also been proposed to play a role in the clinical benefits of psychiatric treatments. Greater attention to patient heterogeneity and more consistent approaches to assessing treatment effects on HPA function may solidify the value of HPA measures in predicting treatment response or developing novel strategies to manage psychiatric disease.

Intravenous anti-obsessive agents: a review

Oral antidepressants are currently the first-line pharmacotherapy for obsessive-compulsive disorder (OCD), but response rates can often be low and with delayed onset of therapeutic action. Some reports have suggested that intravenous (i.v.) anti-obsessive agents may have faster onset of action and greater efficacy. A Medline search was conducted for all reports pertaining to the use of i.v. antidepressants for OCD. Search terms included: 'intravenous', 'clomipramine', 'selective serotonin reuptake inhibitor', 'tricyclic', 'citalopram', 'sertraline', 'paroxetine', 'fluvoxamine', 'SSRIs' and 'intravenous antidepressants'. Relevant articles mainly investigated clomipramine (CMI) with one open trial examining citalopram. Intravenous agents appear to be well-tolerated, particularly in those who have failed oral agents, and may act more rapidly to produce initial clinical response, although this advantage is often lost over time. Preliminary evidence suggests subgroups of patients with severe treatment-refractory OCD may benefit from i.v. anti-obsessive agents, CMI and citalopram. Larger, controlled trials are needed for more definitive conclusions.

Issues in the pharmacological treatment of obsessive-compulsive disorder

AIMS

Obsessive-compulsive disorder (OCD) preferentially responds to a class of antidepressants called serotonin reuptake inhibitors (SRI). This review discusses certain issues unique to pharmacological treatment of OCD: choice of SRI, dose and duration of treatment, options after first failed SRI trial and treatment of SRI non-responders.

METHODS

We performed a MEDLINE search for pharmacotherapy studies published until December 2006. In addition, the reference sections of major articles, and reviews were also screened. We also considered clinical guidelines and narrative reviews in writing this review.

RESULTS

The SRIs are equally effective in treating OCD. Meta-analyses suggest that clomipramine may be superior to other SRIs. OCD tends to respond to higher doses of SRIs than that used to treat depression. Response to treatment is usually delayed and may take up to 8-12 weeks. Atypical antipsychotics are the only proven augmenting agents in SRI non-responders. Cognitive behaviour therapy (CBT) is an effective treatment strategy in treating OCD and possibly has a role in treating SRI non-responders.

DISCUSSION

Side effect profile and drug-drug interactions largely determine the choice of SRI. Those who fail to respond to one SRI trial may well respond to another SRI trial. Clomipramine is recommended if 2-3 trials of SRIs fail to produce response. Atypical antipsychotics are the first-line augmenting agents in SRI non-responders. CBT should be considered in all patients with OCD and is a potential option in SRI non-responders.

CONCLUSION

OCD is a chronic and debilitating disorder. In responders, SRIs have to be continued in the same doses (if possible) for a minimum of 1-2 years and may be lifelong in those with persistent symptoms and in those with multiple relapses. CBT has to be offered in combination with SRIs wherever facilities for CBT exist.

Contemporary assessment and pharmacotherapy of Tourette syndrome

To develop a guide to clinical assessment and pharmacotherapy for children and adults with Tourette syndrome (TS), we reviewed published literature over the past 25 years to identify original articles and reviews on the assessment and pharmacological treatment of Tourette syndrome, attention-deficit/hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD). The literature search also included a survey of reviews published in book chapters. The assessment section was compiled from several reviews. Pharmacological treatments were classified into those with strong empirical support (as evidenced by two positive placebo-controlled studies for tics, OCD, or ADHD in TS samples); modest empirical support (one positive placebo-controlled study), or minimal support (open-label data only). We conclude that accurate diagnosis, including identification of comorbid conditions, is an essential step toward appropriate treatment for patients with TS. In many patients with TS, symptom management requires pharmacotherapy for tics or coexisting conditions. The evidence supporting efficacy and safety for medications used in patients with TS varies. But this evidence offers the best guide to clinical practice.

Predictors of response in anxiety disorders

Anxiety disorder variables such as duration, severity of illness, and comorbidity with other anxiety or mood disorders appear to identify individuals who are at the greatest risk of treatment nonresponse. Conversely, in accord with clinical experience, shorter periods of illness, less severe illness, being treatment naive, and the absence of comorbidity tend to identify patients who are likely to respond robustly to medication management. Symptom clusters in OCD and PTSD are promising as a means of stratifying those more likely to respond to standard pharmacologic treatment. The presence of hoarding or sexual obsessions seems to presage poorer response in OCD, while the presence of dissociative symptoms in PTSD has been linked to high nonspecific treatment response rates to placebo. Genotyping individuals with respect to genes that are thought to have an important role in the underlying disease process, such as the work with the 5HTTL-PR allele, is exciting and is perhaps the first glimmer of using genotyping to identify treatment strategies or to predict the likelihood or speed of response. The use of neuroimaging as a means of identifying individuals who may respond favorably to pharmacologic or neurosurgical intervention is still in its infancy. As a strategy, it may help combine symptom severity and response variables into a clear neurobiologic vulnerability model of illness. In the future, it may be possible to identify specific treatment interventions for specific patterns of abnormal metabolic rates in certain areas of the brain. However, it should be emphasized that such an approach has not been empirically demonstrated in a rigorous experimental context at this time.

Neuroendocrine predictors of response to intravenous clomipramine therapy for refractory obsessive-compulsive disorder

The current study examines the neuroendocrine response to intravenous clomipramine (IV CMI) in oral CMI-resistant obsessive-compulsive disorder (OCD) patients on day 1 and day 14 of treatment to identify predictors of response. Forty-four OCD patients with an inadequate response or poorly tolerant to oral CMI were begun at 25 mg IV CMI, increasing to 250 mg by day 10, and continuing on that dose to day 14. On day 1, plasma levels of prolactin (PRL), growth hormone (GH), and cortisol were obtained immediately before the 25 mg IV infusion, and at five 30-minute time points after the infusion. On day 14, hormonal samples were obtained in a similar fashion. Response was assessed by the Clinical Global Impressions (CGI). Low PRL(MAX) to IV CMI and low cortisol levels overall on day 1 were both significantly associated with clinical response at day 14. An overall increase in growth hormone (GH) secretion during the day 14 testing was associated with positive response. A pronounced PRL response to IV CMI on day 14 was exhibited by the nonresponders, whereas a smaller and later but significant increase in PRL was noted in the responders. The findings suggest that in this sample of oral CMI-resistant patients with OCD, neuroendocrine measures derived from pharmacological challenge with IV CMI are capable of distinguishing IV CMI treatment responders from nonresponders. The limitations of IV CMI as a specific probe of serotonin function are discussed.

The neurobiology of anxiety disorders: implications for psychiatric nursing practice

This era of neurobiological advances challenges psychiatric nurses to develop innovative practice models that address the needs of clients with anxiety disorders. Technological discoveries and molecular and genetic research provide a wealth of evidence-based data that serve as the basis of symptom management, prevention, and health promotion and maintenance in clients experiencing anxiety disorders. This article provides an overview of current data-based studies and conceptual models of various anxiety disorders and their key components. Underpinnings include the interrelationship among neurotransmitter systems, neuroendocrinological processes, and neuroanatomical structures and their role in mediating stress, normal anxiety, and various anxiety disorders. Treatment considerations are also an integral part of this article. The discussion of pharmacologic and nonpharmacological interventions reflect dysregulation of intricate neurobiologic processes and concurrent behaviors and individual client needs.

Serotonin, cerebral blood flow, and cerebral metabolic rate in geriatric major depression and normal aging

While there is substantial evidence for abnormalities in serotonin (5-HT) neurotransmission in major depressive disorder (MDD), almost all of the findings derive from studies of young adults. Moreover, relatively little research has assessed brain 5-HT transmission in vivo. Neuroendocrine studies do not permit evaluation of a range of brain regions, but only the limited circuitry associated with hormone release. Data from autopsy studies are limited by the difficulties of assessment of the acute clinical picture before death, and by post-mortem artifacts. In vivo neuroimaging techniques overcome many of the methodological limitations of both these approaches. There is a large body of imaging data indicating regional cerebral blood flow (rCBF) and cerebral metabolic rate (rCMR) decrements both with aging and in patients with MDD. While the physiological bases for these phenomena are largely unknown, changes in brain 5-HT function may be involved. Neuroanatomical studies have revealed an intricate network of 5-HT-containing neurons within the cerebral microvasculature, with physiological evidence for serotonergic control of both rCBF and rCMR. Acute pharmacological challenges are available to probe brain 5-HT function. Such paradigms, using neuroendocrine responses as endpoints, have been of some utility in predicting outcome with antidepressant treatment. The role of 5-HT dysregulation in geriatric MDD takes on more importance given concerns regarding putative reduced efficacy of serotonin-specific reuptake inhibitors (SSRIs) in this population. If this is due to diminished responsivity of 5-HT systems, then the ability to identify antidepressant nonresponders via 5-HT challenge in combination with neuroimaging measures may have important clinical utility.