Nicotine augmentation for refractory obsessive-compulsive disorder. A case report

Central cholinergic transmission affects the compulsive-like behavior of mice in marble-burying test

The presence of the cholinergic system in the brain areas implicated in the precipitation of obsessive-compulsive behavior (OCB) has been reported but the exact role of the central cholinergic system therein is still unexplored. Therefore, the current study assessed the effect of cholinergic analogs on central administration on the marble-burying behavior (MBB) of mice, a behavior correlated with OCB. The result reveals that the enhancement of central cholinergic transmission in mice achieved by intracerebroventricular (i.c.v.) injection of acetylcholine (0.01 µg) (Subeffective: 0.1 and 0.5 µg), cholinesterase inhibitor, neostigmine (0.1, 0.3, 0.5 µg/mouse) and neuronal nicotinic acetylcholine receptor agonist, nicotine (0.1, 2 µg/mouse) significantly attenuated the number of marbles buried by mice in MBB test without affecting basal locomotor activity. Similarly, central injection of mAChR antagonist, atropine (0.1, 0.5, 5 µg/mouse), nAChR antagonist, mecamylamine (0.1, 0.5, 3 µg/mouse) per se also reduced the MBB in mice, indicative of anti-OCB like effect of all the tested cholinergic mAChR or nAChR agonist and antagonist. Surprisingly, i.c.v. injection of acetylcholine (0.01 µg), and neostigmine (0.1 µg) failed to elicit an anti-OCB-like effect in mice pre-treated (i.c.v.) with atropine (0.1 µg), or mecamylamine (0.1 µg). Thus, the findings of the present investigationdelineate the role of central cholinergic transmission in the compulsive-like behavior of mice probably via mAChR or nAChR stimulation.

Compulsive-like Behaviors in Amyloid-β 1-42-Induced Alzheimer's Disease in Mice Are Associated With Hippocampo-cortical Neural Circuit Dysfunction

Background

In addition to memory deficits, patients with Alzheimer's disease (AD) experience neuropsychiatric disturbances. Recent studies have suggested the association of obsessive-compulsive disorder with the early stages of AD. However, there is a lack of understanding of the neurobiological underpinnings of compulsive-like behaviors at the neuronal circuit level and their relationship with AD.

Methods

We have addressed this issue in an amyloid-β 1-42-induced mouse model of AD by studying compulsive-like behaviors. Next, we compared the hippocampal and medial prefrontal cortex (mPFC) local field potential pattern and coherence between these regions of control and AD mice. We also assessed the expression pattern of acetylcholine and glutamatergic signaling in these regions, using quantitative polymerase chain reaction.

Results

Our findings show that AD mice exhibit compulsive-like behaviors, as evidenced by enhanced marble burying, nest building, and burrowing. Furthermore, AD mice exhibited hippocampo-cortical circuit dysfunction demonstrated by decreased power of rhythmic oscillations at the theta (4-12 Hz) and gamma (25-50 Hz) frequencies in the hippocampus and mPFC, two functionally interconnected brain regions involved both in AD and compulsive behaviors. Importantly, coherence between the hippocampus and mPFC in the theta band of AD animals was significantly reduced. Furthermore, we found reduced cholinergic and glutamatergic neurotransmission in the hippocampus and mPFC of AD mice.

Conclusions

We conclude that the hippocampo-cortical functional alterations may play a significant role in mediating the compulsive-like behaviors observed in AD mice. These findings may help in understanding the underlying circuit mechanisms of obsessive-compulsive disorder-like phenotypes associated with AD.

Use of Selective Alternative Therapies for Treatment of OCD

About 40% of the people with the obsessive-compulsive-disorder do not experience the desired outcome after the existing treatment, and its several side effects were reported. This systematic review was conducted to evaluate the efficacy and tolerability of alternative drugs and assess the possibility of their use as treatment options for obsessive-compulsive-disorder. The Scientific databases PubMed, Science Direct, Google Scholar, Cochrane, Directory of Open Access Journals, MedRxiv and BioRxiv, were searched from inception to March 2022, using appropriate search strategies for each drug and following the Prisma guidelines 2020. Studies were selected according to the already set criteria and assessed for bias. Data were extracted, and descriptive and continuous data were analyzed and presented as frequency/percentage and mean. A total of 16 observational and interventional studies were included for data extraction. The studies focused on four drugs, Psilocybin (n=4), Cannabis (n=7), Nicotine (n=3), and Morphine (n=2), that were used to test out their effect on OCD symptoms. Overall, the majority of the studies showed promising results by documenting a reduction in Y-BOCS scores. However, few subjects, specifically those using nicotine or Cannabis, did not affect their condition or self-reported worsening symptoms. Few side effects were also noticed. This systematic review found that the drugs mostly showed a positive response. All Psilocybin and morphine users, 88.2% and 74.1% of the nicotine and Cannabis users, respectively, reported experiencing the positive effect of these drugs, indicating that these drugs have the potential to be used in the management of OCD. However, further research is required in this arena to thoroughly understand the mechanism of action by which these drugs produce their therapeutic effect. Policies to destigmatize and encourage clinical trials with these drugs are crucial for exploring the use of these drugs as a treatment option for OCD.

Bidirectional Behavioral Selection in Mice: A Novel Pre-clinical Approach to Examining Compulsivity

Obsessive-compulsive disorder (OCD) and related disorders (OCRD) is one of the most prevalent neuropsychiatric disorders with no definitive etiology. The pathophysiological attributes of OCD are driven by a multitude of factors that involve polygenic mechanisms, gender, neurochemistry, physiological status, environmental exposures and complex interactions among these factors. Such complex intertwining of contributing factors imparts clinical heterogeneity to the disorder making it challenging for therapeutic intervention. Mouse strains selected for excessive levels of nest- building behavior exhibit a spontaneous, stable and predictable compulsive-like behavioral phenotype. These compulsive-like mice exhibit heterogeneity in expression of compulsive-like and other adjunct behaviors that might serve as a valuable animal equivalent for examining the interactions of genetics, sex and environmental factors in influencing the pathophysiology of OCD. The current review summarizes the existing findings on the compulsive-like mice that bolster their face, construct and predictive validity for studying various dimensions of compulsive and associated behaviors often reported in clinical OCD and OCRD.

Efficacy of nicotine administration on obsessions and compulsions in OCD: a systematic review

BACKGROUND

Preliminary studies have tested nicotine as a novel treatment for OCD patients who respond partially/incompletely or not at all to first and second-line treatment strategies, with the former represented by SSRIs or clomipramine, and the latter by switching to another SSRI, or augmentation with atypical antipsychotics, and/or combination with/switching to cognitive-behavioural therapy. Some studies found nicotine-induced reduction of obsessive thoughts and/or compulsive behaviour in OCD patients. We aimed to evaluate the efficacy of nicotine administration in OCD patients.

METHODS

We searched the PubMed, ScienceDirect Scopus, CINHAL, Cochrane, PsycINFO/PsycARTICLES, and EMBASE databases from inception to the present for relevant papers. The 'Preferred Reporting Items for Systematic Review and Meta-Analyses' (PRISMA) standards were used. We included all studies focusing on the effects of nicotine administration on OCD patients' obsessions or compulsions. Studies could be open-label, cross-sectional, randomized controlled trials, case series or case reports.

RESULTS

A total of five studies could be included. Nicotine administration may ameliorate behavioural features and recurrent thoughts of severe, treatment-resistant OCD patients; however, in one study it was not associated with OC symptom improvement or cognitive enhancement across various executive function subdomains.

CONCLUSIONS

Although encouraging, the initial positive response from the use of nicotine in OCD needs testing in large controlled studies. This, however, raises ethical issues related to nicotine administration, due to its addiction potential, which were not addressed in the limited literature we examined. As an alternative, novel treatments with drugs able to mimic only the positive effects of nicotine could be implemented.

Donepezil as Add-on Treatment for Resistant Obsessive-Compulsive Disorder: Retrospective Case Series

Obsessive-compulsive disorder (OCD) is one of the most common and disabling psychiatric disorders. Treatment with serotonin selective reuptake inhibitors (SSRIs) shows significant improvement; however, residual symptoms remain in most patients despite continued adequate OCD treatment. For patients exhibiting partial or no response to multiple SSRIs, augmentation strategies are usually recommended. Here, we introduce a retrospective consecutive sample of aged patients with resistant OCD treated with donepezil augmentation to regular pharmacotherapy.

METHODS

Ten patients (5 males, 5 females; mean [SD] age, 63.8 [7.5] years), suffering from resistant OCD, were openly treated with donepezil 10 mg/d as add-on. Efficacy was assessed at baseline and after 8 weeks of treatment using the Yale-Brown Obsessive Compulsive Scale, Clinical Global Impression-Severity, and Clinical Global Impression-Improvement.

RESULTS

The treatment was generally well tolerated without adverse events. In all patients, mean (SD) Yale-Brown Obsessive Compulsive Scale scores diminished from 27.3 (4.3) points at baseline to 16.9 (4.5) points at week 8 (P < 0.0001). Mean (SD) Clinical Global Impression-Severity scores diminished from 5.5 (0.7) points to 3.1 (1.0) points, (P < 0.001). According to Clinical Global Impression-Improvement, 7 patients demonstrated "very much" or "much" improvement and 3 patients did not demonstrate any improvement.

CONCLUSIONS

Donepezil was a well-tolerated add-on to regular pharmacotherapy in treatment-resistant OCD patients in this small cases series. Donepezil could be a promising optional therapy for patients suffering from resistant OCD, but further randomized controlled studies are necessary.

Attenuation of Compulsive-Like Behavior Through Positive Allosteric Modulation of α4β2 Nicotinic Acetylcholine Receptors in Non-Induced Compulsive-Like Mice

Nicotinic α4β2 receptors are the most abundant subtypes of nicotinic acetylcholine receptors (nAChRs) expressed in brain regions implicated in obsessive compulsive disorder (OCD). These receptors are known to modify normal and addictive behaviors by modulating neuronal excitability. Desformylflustrabromine (dFBr) is a novel, positive allosteric modulator (PAM) of high acetylcholine sensitivity (HS) and low acetylcholine sensitivity (LS) α4β2 nAChRs. The present study tested the hypothesis that positive allosteric modulation of α4β2 receptors by dFBr will attenuate compulsive-like behavior in a non-induced compulsive-like mouse model. Male mice (Mus musculus) selected for compulsive-like nesting behavior (NB; 48 animals; 12 per group) received acute (once) and chronic (every day for 32 days) subcutaneous injection of dFBr at 2, 4 and 6 mg/kg doses. Saline was used as a control (0 mg/kg). Compulsive-like NB was assessed after 1, 2, 3, 4, 5 and 24 h, while compulsive-like marble burying (MB) and anxiety-like open field (OF) behaviors were performed 2 h after dFBr administration. In the acute administration protocol, dFBr dose dependently attenuated NB and MB. Rapid effects (1–2 h after drug administration) of dFBr on MB and NB were observed for the chronic administration which was in congruence with the acute study. Chronic administration also revealed sustained suppression of NB by dFBr following 5 weeks of treatment. In both the acute and chronic regimen dFBr did not modulate OF behaviors. This research demonstrates the novel role of positive allosteric modulation of α4β2 nicotinic receptors by dFBr as a translational potential for OCD.

OCDB: a database collecting genes, miRNAs and drugs for obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a psychiatric condition characterized by intrusive and unwilling thoughts (obsessions) giving rise to anxiety. The patients feel obliged to perform a behavior (compulsions) induced by the obsessions. The World Health Organization ranks OCD as one of the 10 most disabling medical conditions. In the class of Anxiety Disorders, OCD is a pathology that shows an hereditary component. Consequently, an online resource collecting and integrating scientific discoveries and genetic evidence about OCD would be helpful to improve the current knowledge on this disorder. We have developed a manually curated database, OCD Database (OCDB), collecting the relations between candidate genes in OCD, microRNAs (miRNAs) involved in the pathophysiology of OCD and drugs used in its treatments. We have screened articles from PubMed and MEDLINE. For each gene, the bibliographic references with a brief description of the gene and the experimental conditions are shown. The database also lists the polymorphisms within genes and its chromosomal regions. OCDB data is enriched with both validated and predicted miRNA-target and drug-target information. The transcription factors regulations, which are also included, are taken from David and TransmiR. Moreover, a scoring function ranks the relevance of data in the OCDB context. The database is also integrated with the main online resources (PubMed, Entrez-gene, HGNC, dbSNP, DrugBank, miRBase, PubChem, Kegg, Disease-ontology and ChEBI). The web interface has been developed using phpMyAdmin and Bootstrap software. This allows (i) to browse data by category and (ii) to navigate in the database by searching genes, miRNAs, drugs, SNPs, regions, drug targets and articles. The data can be exported in textual format as well as the whole database in.sql or tabular format. OCDB is an essential resource to support genome-wide analysis, genetic and pharmacological studies. It also facilitates the evaluation of genetic data in OCD and the detection of alternative treatments.

Demographic, psychosocial, and genetic risk associated with smokeless tobacco use among Mexican heritage youth

BACKGROUND

Despite well-established negative health consequences of smokeless tobacco use (STU), the number and variety of alternative non-combustible tobacco products on the market have increased tremendously over the last 10 years, as has the market share of these products relative to cigarettes. While STU among non-Hispanic white youth has decreased over the last 10 years, the prevalence has remained constant among Hispanic youth. Here we examine demographic, psychosocial, and genetic risk associated with STU among Mexican heritage youth.

METHODS

Participants (50.5 % girls) reported on psychosocial risk factors in 2008-09 (n = 1,087, mean age = 14.3 years), and smokeless tobacco use in 2010-11 (mean age = 16.7 years). Participants provided a saliva sample that was genotyped for genes in the dopamine, serotonin and opioid pathways.

RESULTS

Overall 62 (5.7 %) participants reported lifetime STU. We identified five single nucleotide polymorphisms that increased the risk for lifetime use. Specifically, rs2023902 on SERGEF (OR = 1.93; 95 % CI: 1.05-3.53), rs16941667 on ALDH2 (OR = 3.14; 95 % CI: 1.65-5.94), and rs17721739 on TPH1 (OR = 1.71; 95 % CI: 1.00-2.91) in the dopamine pathway, rs514912 on TRH-DE (OR = 1.84; 95 % CI: 1.25-2.71) in the serotonin pathway, and rs42451417 on the serotonin transporter gene, SLC6A4 (OR = 3.53; 95 % CI: 1.56-7.97). After controlling for genetic risk, being male (OR = 1.86; 95 % CI: 1.02-3.41), obesity status (OR = 2.22; 95 % CI: 1.21-4.09), and both higher levels of anxiety (OR = 1.04; 95 % CI: 1.01-1.08) and social disinhibition (OR = 1.26; 95 % CI: 1.07-1.48) were associated with increased use. High subjective social status (OR = 0.78; 95 % CI: 0.64-0.93) was protective against use, while higher parental education (OR = 2.01; 95 % CI: 1.03-3.93) was associated with increased use.

CONCLUSIONS

These data suggest that use of genetic risk, along with psychosocial, demographic, and behavioral risk factors may increase our ability to identify youth at increased risk for STU, which in turn may improve our ability to effectively target prevention messages to Mexican heritage youth.

Performance of motor associated behavioural tests following chronic nicotine administration

Background

Nicotine has shown potential therapeutic value for neurodegenerative diseases though there are concerns that it may induce behavioural deficits.

Purpose

The present study sought to determine the effect of chronic nicotine administration on overall motor functions and coordination.

Methods

Forty adult female and male Wistar rats were randomly grouped into 4 groups. Treated groups were administered nicotine via subcutaneous injections at doses of 0.25, 2 and 4 mg/kg body weight for 28 days. Control groups received normal saline. All animals were monitored for the first few minutes after each injection for any observed immediate effect of drug administration. Motor associated behavioural tests performed include: open field test, string test for grip strength and limb impairment, movement initiation and step test.

Results

Nicotine induced muscular convulsions within the first 1-5 minutes following daily subcutaneous injections, throughout the period of administration. This was observed to be more severe in females. Nicotine did not produce major alterations in overall motor functions and coordination in both females and males.

Conclusion

The present study shows chronic nicotine treatment produces muscular convulsion but no major deficit in overall motor function and coordination and that any observed alterations may just be transient effects.

Cigarette smoking in obsessive-compulsive disorder and unaffected parents of OCD patients

BACKGROUND

Cigarette smoking is more prevalent among individuals with psychiatric disorders than the general population. Obsessive-compulsive disorder (OCD) may be an intriguing exception, although no recent study has investigated this hypothesis in OCD patients. Moreover, it is unknown whether reduced smoking rates are present in unaffected first-degree relatives of OCD patients.

METHODS

We assessed smoking prevalence in adults with OCD and unaffected parents of youth with OCD (PYOCD). To this end, 113 adults with OCD completed online questionnaires assessing symptom severity and smoking status. Smoking status was obtained from an independent sample of 210 PYOCD assessed for psychiatric diagnoses.

RESULTS

Smoking prevalence rates in adults with OCD (13.3%; n=15) and PYOCD (9.5%; n=20) samples were significantly lower than those found in representative samples of the general population (19-24%, all P<.001) and Axis I disorders (36-64%; all P<.001). There were no smokers in the adult OCD subset without clinically significant depressive symptoms (n=54).

CONCLUSION

Low prevalence of smoking in OCD may be familial and unique among psychiatric disorders, and might represent a possible state-independent OCD marker. Hypotheses concerning the uncharacteristically low prevalence rates are discussed with relation to OCD phenomenology and pathophysiology.

The role of the cholinergic system in the signal attenuation rat model of obsessive-compulsive disorder

RATIONALE

In comparison to studies of the involvement of the serotonergic, dopaminergic, and glutamatergic systems in the pathophysiology of obsessive-compulsive disorder (OCD), research on the involvement of the cholinergic system in this disorder has remained sparse.

OBJECTIVES

The aim of this study was to test the role of the cholinergic system in compulsive behavior using the signal attenuation rat model of OCD. In this model, "compulsive" behavior is induced by attenuating a signal indicating that a lever-press response was effective in producing food.

METHODS

The acetylcholinesterase inhibitor physostigmine (0.05, 0.10, and 0.15 mg/kg), the nicotinic agonist nicotine (0.03, 0.06, 0.10, 0.30, 0.60, and 1.00 mg/kg), the nicotinic antagonist mecamylamine (1, 3, 5, and 8 mg/kg), the muscarinic agonist oxotremorine (0.0075, 0.0150, and 0.0300 mg/kg), and the muscarinic antagonist scopolamine (0.15, 0.50, 1.00, and 1.50 mg/kg) were acutely administered to rats just before assessing their lever-press responding following signal attenuation (experiments 1, 3, 5, 7, and 9, respectively). Because the effects of signal attenuation are assessed under extinction conditions, drug doses that were effective in the above experiments were also tested in an extinction session of lever-press responding that was not preceded by signal attenuation (experiments 2, 4, 6, 8, and 10).

RESULTS

Acute systemic administration of the cholinergic agents did not exert a selective anti- or pro-compulsive effect in the signal attenuation model.

CONCLUSIONS

Acetylcholine does not seem to play a role in the signal attenuation rat model of OCD.

Pharmacotherapy of obsessive-compulsive disorder: evidence-based treatment and beyond

BACKGROUND

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder associated with a significant degree of functional disability and poor quality of life. Pharmacotherapy may have a substantial impact on the course and outcome of OCD.

METHOD

We review the evidence supporting available strategies for the pharmacological treatment of OCD.

RESULTS

Selective serotonin reuptake inhibitors (SSRIs) remain the pharmacological treatment of choice and are associated with improved health-related quality of life. Discontinuation is associated with relapse and loss of quality of life, implying treatment should continue long-term. A substantial minority of patients who fail to respond to SSRI may benefit from dose elevation or adjunctive antipsychotics, though long-term trials validating the effectiveness and tolerability of these strategies are relatively lacking.

CONCLUSION

The pharmacological evidence-base for the treatment of OCD is becoming increasingly robust. Treatment with SSRIs and clomipramine remains uncontroversial and improvements are sustained over time. Newer compounds targeting serotonin receptor subtypes and other neurotransmitter systems are undergoing evaluation.

Drug treatment of obsessive-compulsive disorder

Knowledge of pharmacotherapeutic treatment options in obsessive-compulsive disorder (OCD) has grown considerably over the past 40 years. Serotonergic antidepressants, such as selective serotonin reuptake inhibitors (SSRIs) and clomipramine, are the established pharmacologic first-line treatment of OCD. Medium to large dosages and acute treatment for at least 3 months are recommended until efficacy is assessed. In case of significant improvement, maintenance treatment is necessary. Unfortunately, about half of the patients do not respond sufficiently to oral serotonergic antidepressants; augmentation with atypical antipsychotics is an established second-line drug treatment strategy. Alternatives include intravenous serotonergic antidepressants and combination with or switch to cognitive behavioral psychotherapy. Remarkably, a considerable proportion of OCD patients still do not receive rational drug treatment. Novel research approaches, such as preliminary treatment studies with glutamatergic substances, and trials with further drugs, as well as needed aspects of future research, are reviewed.

Impaired P50 suppression in fear extinction in obsessive-compulsive disorder

The processes of fear conditioning and extinction are thought to be related to the pathophysiology of anxiety disorders including obsessive-compulsive disorder (OCD). We have reported alterations of auditory P50 suppression in human fear conditioning and extinction in healthy control subjects (Kurayama et al., 2009). In the study, P50 suppression was impaired transiently in the course of fear acquisition and extinction. In this study, we investigated the changes of P50 suppression with OCD patients in the course of the same experimental paradigm. 39 patients with OCD and 21 healthy control subjects were recruited. In the acquisition phase of classical fear conditioning, 10 pairings of the conditioned stimulus (CS; the visual stimulus from a light-emitting diode) and the unconditioned stimulus (US; the electrical stimulus to the wrist) were administered, and in the extinction phase, 10 CS without US were administered. P50 auditory evoked potentials were measured as the first stimulus sound (S1) and the second stimulus sound (S2) in double-click paradigm with a 500 ms interval. P50 S2/S1 ratio was used to evaluate P50 suppression. The mean P50 S2/S1 ratio in patients with OCD significantly elevated from baseline level during the fear acquisition as that in healthy controls, but the elevated S2/S1 ratio did not recover to baseline level. The S2/S1 ratio in the extinction phase was significantly higher in the OCD patient group than in the healthy control group. In conclusion, our data suggested that P50 sensory gating in fear extinction was impaired in patients with OCD.

New pharmacotherapeutic approaches to obsessive-compulsive disorder

This article summarizes results of all pharmacotherapy trials for obsessive-compulsive disorder (OCD) published from 2006 to 2008 as well as studies on markers for predicting response to treatment and neurobiological changes induced by pharmacotherapy. Results show that recent developments in the treatment of OCD have been modest and primarily involve evidence for the efficacy of escitalopram and other selective serotonin reuptake inhibitors (SSRIs); augmentation with antipsychotics in treatment-refractory patients and combination treatment with D-cycloserine and cognitive-behavioral therapy has also been effective. The efficacy of serotonin-norepinephrine reuptake inhibitors remains inconclusive. Studies on markers of clinical response have shown inconsistent results, however, duration and severity of OCD and the presence of comorbidities can often identify patients at risk for nonresponse. Lastly, successful treatment with an SSRI results in both serotonergic and dopaminergic changes, but more research is necessary in order to define the biological characteristics of responders and nonresponders.

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.

An update on the pharmacological treatment of obsessive-compulsive disorder

The purpose of this article is to introduce the reader to an updated evidence-based drug treatment algorithm to be employed in patients with obsessive-compulsive disorder (OCD). Relevant studies were identified through a comprehensive review and classified according to the type of patients enrolled, the quality of the study design and the invasiveness, availability and complexity of the therapeutic approach. When ineffective, therapeutic trials with first-line strategies (such as the selective serotonin re-uptake inhibitors [SSRIs] and venlafaxine) should be followed by treatment approaches such as clomipramine, augmentation with antipsychotics or pindolol, SSRI megadoses or cognitive behavioral therapy. These therapeutic strategies are expected to help most patients with OCD. Additional approaches include intravenous clomipramine, oral morphine, 'heroic drug strategies', deep brain stimulation and functional neurosurgery. Independent studies are urgently needed to help identify the most promising drug treatment sequences for OCD.

Relationship between obsessive-compulsive symptoms and smoking habits amongst schizophrenic patients

The rate of smoking is especially high among patients with schizophrenia (SCH) and schizoaffective disorder (SCHAFF). Patients with obsessive-compulsive disorder (OCD) smoke less than the general population. OCD symptoms are more frequent among patients with SCH or SCHAFF than in the general population, but it is still unclear whether schizophrenia patients with OC symptoms suffer from SCH and comorbid OCD, or whether they represent a unique subgroup of SCH with presenting OC symptoms. In our study we hypothetised that the current smoking rate of schizophrenia patients with OC symptoms is lower than in schizophrenia patients without OC symptoms. We assessed OC symptoms with the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), general state with the Brief Psychiatric Rating Scale (BPRS) and smoking habits with a questionnaire among 66 patients with SCH or SCHAFF. We formed two groups by dividing patients according to their Y-BOCS score. Group I consisted of patients with Y-BOCS scores under 16, while group II consisted of patients with Y-BOCS scores above 16, and we compared the current smoking rates of the two groups. We found that the rates did not differ significantly, so we came to the conclusion that OC symptoms are not in a tight relationship with smoking habits among patients with SCH/SCHAFF.

Memantine augmentation for refractory obsessive-compulsive disorder

Glutamatergic hyperactivity hypothesis in obsessive-compulsive disorder (OCD) has been proposed but not tested. Memantine is an uncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist. We report two cases of refractory obsessive-compulsive disorder treated with an augmentation of memantine at 15 mg/day. The first case did not benefit from such treatment, while the second showed immediate and substantial improvement. Contrasting results, reflecting different subtypes of OCD, are discussed. We hypothesized that in certain OCD subtypes an agent that enhances memory for actions may promote a reduction in orbitofrontal activation.

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.