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

Intravenous Clomipramine for Treatment-Resistant Obsessive-Compulsive Disorder

BACKGROUND

This open trial was conducted to evaluate the effectiveness of intravenous clomipramine (CMI) in refractory obsessive-compulsive disorder (OCD).

METHODS

Thirty OCD poor responders to previous multiple trials of anti-obsessive medications were selected and admitted to the hospital. Severity of the illness and response to treatment were primarily assessed by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). CMI was gradually administered intravenously for one week. All patients were thereafter switched to oral CMI with a maximum dose of 225 mg/day.

RESULTS

The Y-BOCS total score mean at admission was in the severe range (24-31), and dropped on discharge and follow-ups to the moderate range (16-23). At discharge, 23 patients (76.7%) had a decrease in Y-BOCS ≥ 25% and were considered responders, while only 18 (60%) were still responders at 24 weeks. No relevant persistent side effects were reported.

CONCLUSION

Intravenous clomipramine could be of benefit for severe OCD cases that have not adequately responded to several therapies, including oral clomipramine.

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.

Effects of intravenous antidepressant drugs on the excitability of human motor cortex: a study with paired magnetic stimulation on depressed patients

BACKGROUND

The effect of various drugs was investigated by using transcranial magnetic stimulation (TMS) both in healthy subjects and patients, and the results indicated an influence of antidepressant drugs (ADs) on motor excitability.

OBJECTIVE

The aim of our study was to analyze the effects of two ADs, the tricyclic (TCA) clomipramine and the serotoninergic antidepressant (SSRI) citalopram on the motor cortex excitability in major depressed patients with TMS.

METHODS

Thirty affected subjects were placed into three groups: two received an intravenous dose of 25 mg clomipramine or 40 mg citalopram, and one received an injection of a placebo. Motor cortex excitability was studied by single and paired TMS before and after 3.5, 8, and 24 hours from administration of the drugs and placebo. Motor cortical excitability was measured using different TMS parameters: resting motor threshold (RMT), motor-evoked potential (MEP) amplitude, intracortical inhibition (ICI), and intracortical facilitation (ICF).

RESULTS

The results indicated a temporary but significant increase of RMT and ICI and a decrease of ICF after the administration of both drugs, with a longer inhibition for the clomipramine rather than the citalopram. MEP amplitude was not significantly affected by the antidepressant injections.

CONCLUSIONS

Our findings highlight that a single intravenous dose of clomipramine or citalopram exerts a significant but transitory suppression of motor cortex excitability in depressed patients. TMS represents a useful research tool in assessing the effects of motor cortical excitability of drugs used in the treatment of mental disorders.

Diurnal cortisol levels and cortisol response in youths with obsessive-compulsive disorder

BACKGROUND/AIMS

Recent results indicate a role of the hypothalamic-pituitary-adrenal (HPA) axis in the pathophysiology of obsessive-compulsive disorder (OCD). Although childhood onset is common, the HPA axis has scarcely been studied in young OCD subjects. Therefore, the present study aimed at examining basal and response levels of salivary cortisol in a sample of young OCD subjects.

METHODS

Twenty-three children and adolescents with DSM-IV OCD were compared to a reference group of school children (n = 240-336). The basal cortisol rhythm was measured through saliva samples 3 times/day. The cortisol response to a psychological stressor (exposure therapy in the OCD group and a fire alarm in the reference group) was also examined.

RESULTS

Compared to the reference group, OCD subjects displayed higher early-morning cortisol values (p = 0.005) with no difference between the late-morning and evening values. The cortisol levels in the OCD group diminished in response to the psychological stressor, compared to a positive response in the reference group (p < 0.001). No relation was found between cortisol and clinical parameters.

CONCLUSION

These results support the idea that HPA hyperactivity, commonly found in adult OCD patients, is also present at an earlier stage of development, with specificity for the early-morning peak.

Obsessive-compulsive disorder spectrum as a scientific "metaphor"

As a result of clinical, epidemiological, neuroimaging, and therapy studies that took place in the late 1980s, obsessive-compulsive disorder (OCD) has been well-characterized in the field of anxiety disorders. Other disorders attracted attention for their similarities to OCD, and were located in the orbit of the disorder. OCD has become known as the "primary domain" of a scientific "metaphor" comprising the putative cluster of OCD-related disorders (OCRDs). It is a "paradigm" with which to explore basal ganglia dysfunction. The OCRDs share common phenomenology, comorbidities, lifetime course, demographics, possible genetics, and frontostriatal dysfunction (particularly caudate hyperactivity.) The adoption of this metaphor analogy has proven useful. However, 15 years since its emergence, the spectrum of obsessive-compulsive disorders remains controversial. Questions under debate include whether OCD is a unitary or split condition, whether it is an anxiety disorder, and whether there exists only one spectrum or several possible spectrums. Further work is needed to clarify obsessive-compulsive symptoms, subtypes, and endophenotypes. There is need to integrate existing databases, better define associated symptom domains, and create a more comprehensive endophenotyping protocol for OCRDs. There is also a need to integrate biological and psychological perspectives, concepts, and data to drive this evolution. By increasing research in this field, the OCD spectrum may evolve from a fragmented level of conceptualization as a "metaphor" to one that is more comprehensive and structured.

Outcome predictors for severe obsessive-compulsive patients in intensive residential treatment

Intensive residential treatment (IRT) is an effective management approach for those with severe obsessive-compulsive disorder (OCD). This study aimed to identify IRT response predictors for clinical and research use. Consecutive subjects admitted to the Massachusetts General Hospital/McLean OCD Institute (OCDI) between February 1997 and June 2003 were included (N=476). IRT responder and non-responder group characteristics were compared using t-tests and chi(2) analyses. Multiple regression analysis modeled relationships between final OCD severity (Yale-Brown Obsessive-Compulsive scale scores) and predictor variables, while accounting for multicollinearity and potential outliers. Treatment responders comprised 59.3% of the treatment sample. Responders had significantly fewer males (p=0.02), lower depression severity (p=0.03), poorer psychosocial functioning (p=0.03) and fewer tic disorders (0.04), but were not different with respect to admission length, age, marital or employment status, OCD onset, family OCD history, treatment or admission history. In the final regression model, decreased initial OCD severity (p<0.001), female gender (p=0.003) and better initial psychosocial functioning (Work and Social Adjustment scale scores) (p=0.003) were predictors of less severe OCD at discharge (adjusted R-square=0.28). Depression severity (Beck Depression Inventory scores) and insight were not predictive of treatment outcome. Future research is necessary to elucidate putative relationships between gender and OCD psychopathology, and to understand the interplay of psychosocial factors, OCD severity and treatment outcome.

Pharmacotherapy of obsessive-compulsive disorder and obsessive-compulsive spectrum disorders

This article reviews new developments of pharmacotherapy in obsessive-compulsive disorder (OCD) and OC spectrum disorders of the past five years. New developments primarily involved the ex-tension of evidence of efficacy of serotonin reuptake inhibitors(SRIs), the use of atypical antipsychotics in addition to SRIs for treatment refractory patients, the combination of pharmacotherapy with behavior therapy, and studies assessing predictors of response. Today, frontline pharmacological treatment of OCD still consists of drugs with potent serotonin reuptake inhibition proper-ties. In case of non-response, treatment options comprise adding another drug, increasing the dose, switching drugs, or changing the mode of delivery.

Doxapram-induced panic attacks and cortisol elevation

Numerous agents with differing biological properties and central nervous system (CNS) effects can induce panic attacks in predisposed individuals. A potential explanation of this finding is that panic disorder patients are more likely to panic than normal control subjects when given a panicogen due to an excessive fear response to somatic arousal. We test this hypothesis by using doxapram, a panicogen with minimal CNS effects, to induce panic in patients and control subjects. Doxapram was given to six subjects with panic disorder with or without agoraphobia and four healthy volunteers. Measures comprised the Acute Panic Inventory, the Borg Exertion scale, the 10-point Anxiety Scale, the 10-point Apprehension Scale, cortisol, prolactin, and MHPG, all obtained at baseline and multiple time points after the doxapram infusion. All panic disorder patients panicked with doxapram, whereas no control subjects had a panic attack. Panic patients had similar levels of breathlessness with doxapram compared with control subjects. Although panic patients had higher levels of anxiety and apprehension, these did not change significantly with doxapram compared with control levels. Doxapram led to similar increases in cortisol and prolactin in both groups, and MHPG was consistently elevated in panic patients, but unaffected by doxapram. These results show that doxapram is a useful panicogen in the study of panic disorder. Since the panic patients and control subjects had similar levels of physiological and psychological arousal, but the panic patients were more likely to have a panic attack, this lends support to the concept of a sensitized fear network in panic disorder patients.

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.