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1.
Can J Psychiatry ; 66(2): 159-169, 2021 02.
Article in English | MEDLINE | ID: mdl-32677851

ABSTRACT

OBJECTIVE: Patients with depression frequently experience persistent residual symptoms even with optimal interventions. These patients often use complementary treatments, including yoga, as a preferred alternative or adjunctive treatment. There is evidence for the benefit of yoga for depression, but this has not been rigorously evaluated, particularly in bipolar depression. We aimed to determine the feasibility and benefit of manualized breathing-focused yoga in comparison to psychoeducation as augmentation to pharmacotherapy for improving residual symptoms of depression in unipolar and bipolar patients. METHODS: Using a randomized single-blind crossover design, 72 outpatients with unipolar or bipolar depression were augmented with the two 8-week interventions at separate times, as add-ons to current first-line antidepressants and mood stabilizers. The primary outcome measure was the Montgomery-Åsberg Depression Rating Scale (MADRS). Due to the high dropout of participants after crossover at Week 8, analysis focused on between-group comparisons of yoga and psychoeducation during the initial 8 weeks of the study. RESULTS: There was a significant decline in depressive symptoms, as measured by the MADRS, following 8 weeks of yoga. However, there was no significant difference in MADRS ratings between intervention groups. Similar improvements in self-rated depressive symptoms and well-being were also observed across time. CONCLUSIONS: Both yoga and psychoeducation may improve residual symptoms of unipolar and bipolar depression as add-on to medications. In-class group sessions and long study durations may reduce feasibility for this population. Larger trials with parallel group design and shorter duration may be more feasible.


Subject(s)
Bipolar Disorder , Yoga , Antidepressive Agents/therapeutic use , Bipolar Disorder/therapy , Humans , Respiration , Single-Blind Method
2.
Psychol Med ; 50(7): 1173-1181, 2020 05.
Article in English | MEDLINE | ID: mdl-31120006

ABSTRACT

BACKGROUND: Obsessive-compulsive disorder (OCD) is an anxiety disorder with significant morbidity whose pathophysiology is not fully understood. Neuroimaging studies have characterized OCD in terms of elevated striatal and prefrontal reactivity to emotion provocation. This neural model may be informed by investigation of functional connectivity in OCD, identifying alterations in how sensory information is integrated into frontostriatal regions. METHODS: The current study employed functional magnetic resonance imaging (fMRI) to compare neural activity and connectivity in 31 OCD patients (12 washing and 19 checking subtypes) and 17 healthy volunteers in an emotion provocation paradigm using visual stimuli. RESULTS: OCD status was associated with hyper-activation of the posterior cingulate (PCg) in response to emotion provocation. Additionally, OCD patients demonstrated elevated PCg functional connectivity with the visual cortices and frontostriatal regions. Exploratory analyses suggested that stimulus-provoked activity and connectivity was elevated for checking subtypes in motor cortices, and elevated in washing subtypes in the anterior insula and orbitofrontal cortex. CONCLUSIONS: The PCg's role in moderating connectivity between the visual cortex and frontolimbic regions is muted in OCD, consistent with the PCg's suggested role in regulating attention towards emotional stimuli. Exploratory analyses suggest distinct PCg connectivity profiles in OCD subtypes, with checking linked to motor activation, but washing linked to a network supporting emotional salience. The study was not powered to fully investigate the effects of medication, patients often endorsed secondary symptom subtypes that muddied washing/checking distinctions, and the emotion provocation paradigm was of limited intensity compared to life stressors.


Subject(s)
Brain/physiopathology , Obsessive-Compulsive Disorder/physiopathology , Adult , Brain Mapping , Canada , Case-Control Studies , Cerebral Cortex/physiopathology , Emotions/physiology , Female , Gyrus Cinguli/physiopathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prefrontal Cortex/physiopathology , Young Adult
3.
J Affect Disord ; 251: 121-129, 2019 05 15.
Article in English | MEDLINE | ID: mdl-30921595

ABSTRACT

BACKGROUND: Patient outcome expectancy - the belief that treatment will lead to an improvement in symptoms - is linked to favourable therapeutic outcomes in major depressive disorder (MDD). The present study extends this literature by investigating the temporal dynamics of expectancy, and by exploring whether expectancy during treatment is linked to differential outcomes across treatment modalities, for both optimistic versus pessimistic expectancy. METHODS: A total of 104 patients with MDD were randomized to receive either cognitive behavioral therapy (CBT) or pharmacotherapy for 16 weeks. Outcome expectancy was measured throughout treatment using the Depression Change Expectancy Scale (DCES). Depression severity was measured using both the Hamilton Depression Rating Scale and Beck Depression Inventory-II. RESULTS: Latent growth curve models supported improvement in expectancy across both treatments. Cross-lagged panel models revealed that both higher optimistic and lower pessimistic expectancy at mid-treatment predicted greater treatment response in pharmacotherapy. For CBT, the associative patterns between expectancy and depression differed as a function of expectancy type; higher optimistic expectancy at pre-treatment and lower pessimistic expectancy at mid-treatment predicted greater treatment response. LIMITATIONS: The sample size limited statistical power and the complexity of models that could be explored. CONCLUSIONS: Results suggest that outcome expectancy improved during treatment for depression. Whether outcome expectancy represents a specific mechanism for the reduction of depression warrants further investigation.


Subject(s)
Antidepressive Agents/therapeutic use , Cognitive Behavioral Therapy/methods , Depressive Disorder, Major/therapy , Adolescent , Adult , Aged , Depressive Disorder, Major/diagnosis , Depressive Disorder, Major/psychology , Female , Humans , Male , Middle Aged , Pessimism , Psychiatric Status Rating Scales , Surveys and Questionnaires , Treatment Outcome
4.
Psychol Med ; 49(15): 2626-2634, 2019 11.
Article in English | MEDLINE | ID: mdl-30560738

ABSTRACT

BACKGROUND: Although cognitive-behavioural therapy (CBT) is a well-established treatment for adult depression, its efficacy and efficiency may be enhanced by better understanding its mechanism(s) of action. According to the theoretical model of CBT, symptom improvement occurs via reductions in maladaptive cognition. However, previous research has not established clear evidence for this cognitive mediation model. METHODS: The present study investigated the cognitive mediation model of CBT in the context of a randomized controlled trial of CBT v. antidepressant medication (ADM) for adult depression. Participants with major depressive disorder were randomized to receive 16 weeks of CBT (n = 54) or ADM (n = 50). Depression symptoms and three candidate cognitive mediators (dysfunctional attitudes, cognitive distortions and negative automatic thoughts) were assessed at week 0 (pre-treatment), week 4, week 8 and week 16 (post-treatment). Longitudinal associations between cognition and depression symptoms, and mediation of treatment outcome, were evaluated in structural equation models. RESULTS: Both CBT and ADM produced significant reductions in maladaptive cognition and depression symptoms. Cognitive content and depression symptoms were moderately correlated within measurement waves, but cross-lagged associations between the variables and indirect (i.e. mediated) treatment effects were non-significant. CONCLUSIONS: The results provide support for concurrent relationships between cognitive and symptom change, but not the longitudinal relationships hypothesized by the cognitive mediation model. Results may be indicative of an incongruence between the timing of measurement and the dynamics of cognitive and symptom change.


Subject(s)
Antidepressive Agents/therapeutic use , Cognition , Cognitive Behavioral Therapy/methods , Depressive Disorder, Major/psychology , Depressive Disorder, Major/therapy , Adult , Attitude , Female , Humans , Longitudinal Studies , Male , Models, Psychological , Treatment Outcome , Young Adult
5.
Focus (Am Psychiatr Publ) ; 16(1): 85-94, 2018 Jan.
Article in English | MEDLINE | ID: mdl-32015703

ABSTRACT

(Reprinted by permission of SAGE Publications, Inc., from The Canadian Journal of Psychiatry 2016; 61:576-587. Copyright © 2016 by the Authors [https://doi.org/10.1177/0706743716660290]).

6.
JAMA Psychiatry ; 74(8): 833-840, 2017 08 01.
Article in English | MEDLINE | ID: mdl-28636705

ABSTRACT

Importance: For a small percentage of obsessive-compulsive disorder (OCD) cases exhibiting additional neuropsychiatric symptoms, it was proposed that neuroinflammation occurs in the basal ganglia as an autoimmune response to infections. However, it is possible that elevated neuroinflammation, inducible by a diverse range of mechanisms, is important throughout the cortico-striato-thalamo-cortical circuit of OCD. Identifying brain inflammation is possible with the recent advance in positron emission tomography (PET) radioligands that bind to the translocator protein (TSPO). Translocator protein density increases when microglia are activated during neuroinflammation and the TSPO distribution volume (VT) is an index of TSPO density. Objective: To determine whether TSPO VT is elevated in the dorsal caudate, orbitofrontal cortex, thalamus, ventral striatum, dorsal putamen, and anterior cingulate cortex in OCD. Design, Setting, and Participants: This case-control study was conducted at a tertiary care psychiatric hospital from May 1, 2010, to November 30, 2016. Participants with OCD (n = 20) and age-matched healthy control individuals (n = 20) underwent a fluorine F 18-labeled N-(2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide PET scan. It is a high-quality second-generation TSPO-binding PET radiotracer. All participants were drug and medication free, nonsmoking, and otherwise healthy. Main Outcomes and Measures: The TSPO VT was measured in the dorsal caudate, orbitofrontal cortex, thalamus, ventral striatum, dorsal putamen, and anterior cingulate cortex. Compulsions were assessed with the Yale-Brown Obsessive Compulsive Scale. Results: In the OCD and healthy groups, the mean (SD) ages were 27.4 (7.1) years and 27.6 (6.6) years, respectively, and 11 (55%) and 8 (40%) were women, respectively. In OCD, TSPO VT was significantly elevated in these brain regions (mean, 32%; range, 31%-36% except anterior cingulate cortex, 24%; analysis of variance, effect of diagnosis: P < .001 to P = .004). Slightly lower elevations in TSPO VT (22%-29%) were present in other gray matter regions. The Yale-Brown Obsessive Compulsive Scale measure of distress associated with preventing compulsive behaviors significantly correlated with TSPO VT in the orbitofrontal cortex (uncorrected Pearson correlation r = 0.62; P = .005). Conclusions and Relevance: To our knowledge, this is the first study demonstrating inflammation within the neurocircuitry of OCD. The regional distribution of elevated TSPO VT argues that the autoimmune/neuroinflammatory theories of OCD should extend beyond the basal ganglia to include the cortico-striato-thalamo-cortical circuit. Immunomodulatory therapies should be investigated in adult OCD, rather than solely childhood OCD, particularly in cases with prominent distress when preventing compulsions.


Subject(s)
Encephalitis/metabolism , Obsessive-Compulsive Disorder/metabolism , Adult , Anilides/metabolism , Case-Control Studies , Female , Functional Neuroimaging , Humans , Male , Positron-Emission Tomography , Pyridines/metabolism , Receptors, GABA/metabolism , Young Adult
7.
Can J Psychiatry ; 61(9): 576-87, 2016 09.
Article in English | MEDLINE | ID: mdl-27486153

ABSTRACT

BACKGROUND: The Canadian Network for Mood and Anxiety Treatments (CANMAT) conducted a revision of the 2009 guidelines by updating the evidence and recommendations. The scope of the 2016 guidelines remains the management of major depressive disorder (MDD) in adults, with a target audience of psychiatrists and other mental health professionals. METHODS: Using the question-answer format, we conducted a systematic literature search focusing on systematic reviews and meta-analyses. Evidence was graded using CANMAT-defined criteria for level of evidence. Recommendations for lines of treatment were based on the quality of evidence and clinical expert consensus. "Complementary and Alternative Medicine Treatments" is the fifth of six sections of the 2016 guidelines. RESULTS: Evidence-informed responses were developed for 12 questions for 2 broad categories of complementary and alternative medicine (CAM) interventions: 1) physical and meditative treatments (light therapy, sleep deprivation, exercise, yoga, and acupuncture) and 2) natural health products (St. John's wort, omega-3 fatty acids; S-adenosyl-L-methionine [SAM-e], dehydroepiandrosterone, folate, Crocus sativus, and others). Recommendations were based on available data on efficacy, tolerability, and safety. CONCLUSIONS: For MDD of mild to moderate severity, exercise, light therapy, St. John's wort, omega-3 fatty acids, SAM-e, and yoga are recommended as first- or second-line treatments. Adjunctive exercise and adjunctive St. John's wort are second-line recommendations for moderate to severe MDD. Other physical treatments and natural health products have less evidence but may be considered as third-line treatments. CAM treatments are generally well tolerated. Caveats include methodological limitations of studies and paucity of data on long-term outcomes and drug interactions.


Subject(s)
Acupuncture Therapy/standards , Biological Products/therapeutic use , Depressive Disorder, Major/therapy , Evidence-Based Medicine/standards , Exercise Therapy/standards , Phototherapy/standards , Practice Guidelines as Topic/standards , Sleep Deprivation , Acupuncture Therapy/methods , Canada , Exercise Therapy/methods , Humans , Phototherapy/methods
8.
J Neuropsychiatry Clin Neurosci ; 28(3): 243-7, 2016.
Article in English | MEDLINE | ID: mdl-27019066

ABSTRACT

This study investigated the effect of an intravenous serotonin reuptake inhibitor on the neural substrates of obsessive-compulsive disorder (OCD), as intravenous agents may be more effective in treating OCD than conventional oral pharmacotherapy. Eight OCD subjects and eight control subjects received alternate infusions of citalopram and placebo during functional magnetic resonance imaging, in a randomized, symptom-provocation, crossover design. Compared with baseline, OCD subjects displayed significant changes in prefrontal neural activity after the citalopram infusion relative to placebo, and these changes correlated with reductions in subjective anxiety.


Subject(s)
Brain Mapping , Brain/drug effects , Citalopram/administration & dosage , Obsessive-Compulsive Disorder/drug therapy , Selective Serotonin Reuptake Inhibitors/administration & dosage , Administration, Intravenous/methods , Adolescent , Adult , Brain/diagnostic imaging , Double-Blind Method , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Obsessive-Compulsive Disorder/diagnostic imaging , Psychiatric Status Rating Scales , Treatment Outcome , Young Adult
9.
Psychiatry Res ; 220(1-2): 245-50, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25124683

ABSTRACT

Decrements in cognitive function are a common feature of Major Depressive Disorder (MDD), and whether distinct classes of antidepressants differentially affect memory in these individuals has not been sufficiently evaluated. In this study we sought to determine the effect of escitalopram and bupropion XL on memory and psychosocial function. Forty-one individuals (18-50 years) with MDD were enrolled in an 8-week, double-blind, double-dummy, randomized controlled comparative trial of bupropion XL and escitalopram. Thirty-six participants completed pre and post memory assessments. Verbal, non-verbal and working memory were evaluated with a comprehensive neuropsychological battery. Psychosocial function was assessed with the Sheehan Disability Scale and Endicott Work Productivity Scale. Escitalopram and bupropion XL significantly improved immediate as well as delayed verbal and nonverbal memory, global function (all p≤0.001), and work productivity (p=0.045), with no significant between-group differences. Improvement in immediate verbal memory exerted a direct influence on improvement in global function (p=0.006). Treatment with either escitalopram or bupropion XL was associated with improvement in memory and psychosocial function in adults with MDD.


Subject(s)
Antidepressive Agents, Second-Generation/therapeutic use , Bupropion/therapeutic use , Citalopram/therapeutic use , Depressive Disorder, Major/drug therapy , Memory/drug effects , Adolescent , Adult , Antidepressive Agents, Second-Generation/pharmacology , Bupropion/pharmacology , Citalopram/pharmacology , Cognition/drug effects , Depressive Disorder, Major/psychology , Double-Blind Method , Female , Humans , Male , Memory, Short-Term/drug effects , Middle Aged , Neuropsychological Tests , Treatment Outcome , Young Adult
10.
Asian J Psychiatr ; 6(2): 157-61, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23466114

ABSTRACT

Few published studies have evaluated selective serotonin reuptake inhibitors in dysthymia without current co-morbid major depression. In this 12-week study, 40 dysthymic patients were randomly assigned to either placebo (n=19) or 20-40 mg/day of paroxetine (n=21). At endpoint, the paroxetine group showed significantly greater improvement on the Clinical Global Impression Scale, Beck Depression Inventory, and Quality of Life Enjoyment and Satisfaction Questionnaire (p<0.05), and a trend to superiority over placebo on the Hamilton Depression Rating Scale. Response and remission were significantly higher with paroxetine than placebo (p<0.05). There were no significant differences in drop out rates or frequency of adverse effects, except for excessive sweating (greater with paroxetine, p=0.04). Reporting of multiple side effects was also higher with paroxetine than with placebo (p=0.02). Paroxetine is more effective than placebo in improving symptoms and quality of life in dysthymia, and is generally tolerable.


Subject(s)
Dysthymic Disorder/drug therapy , Paroxetine/administration & dosage , Selective Serotonin Reuptake Inhibitors/administration & dosage , Adult , Double-Blind Method , Female , Humans , Male , Middle Aged , Paroxetine/adverse effects , Selective Serotonin Reuptake Inhibitors/adverse effects , Surveys and Questionnaires , Treatment Outcome , Young Adult
11.
Clin Neurophysiol ; 124(7): 1309-20, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23485366

ABSTRACT

OBJECTIVE: To evaluate transcranial magnetic stimulation (TMS) measures of inhibition and excitation in obsessive-compulsive disorder (OCD), major depressive disorder (MDD) and schizophrenia (SCZ). METHODS: Paradigms included: short-interval cortical inhibition (SICI), cortical silent period (CSP), resting motor threshold, intracortical facilitation, and motor evoked potential amplitude. A literature search was performed using PubMed, Ovid Medline, Embase Psychiatry and PsycINFO 1990 through April 2012. RESULTS: A significant Hedge's g was found for decreased SICI (g=0.572, 95% confidence interval [0.179, 0.966], p=0.004), enhanced intracortical facilitation (g=0.446, 95% confidence interval [0.042, 0.849], p=0.030) and decreased CSP (g=-0.466, 95% confidence interval [-0.881, -0.052], p=0.027) within the OCD population. For MDD, significant effect sizes were demonstrated for decreased SICI (g=0.641, 95% confidence interval [0.384, 0.898], p=0.000) and shortened CSP (g=-1.232, 95% confidence interval [-1.530, -0.933], p=0.000). In SCZ, a significant Hedge's g was shown for decreased SICI (g=0.476, 95% confidence interval [0.331, 0.620], p=0.000). CONCLUSION: Inhibitory deficits are a ubiquitous finding across OCD, MDD, SCZ and enhancement of intracortical facilitation is specific to OCD. SIGNIFICANCE: Provides a clear platform from which diagnostic procedures can be developed.


Subject(s)
Evoked Potentials, Motor/physiology , Mental Disorders/pathology , Motor Cortex/physiopathology , Neural Inhibition/physiology , Transcranial Magnetic Stimulation , Databases, Factual/statistics & numerical data , Depressive Disorder, Major/physiopathology , Female , Humans , Male , Mental Disorders/physiopathology , Obsessive-Compulsive Disorder , Reaction Time , Schizophrenia/physiopathology , Time Factors
12.
Hum Psychopharmacol ; 27(4): 419-27, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22782542

ABSTRACT

OBJECTIVE: Heightened anticipation of future events has been characterized as a feature of certain anxiety disorders. In functional magnetic resonance imaging studies, anticipation of fearful/threatening images has been shown to robustly activate the insular cortex and amygdala in healthy subjects, in subjects with high trait anxiety, and in some with anxiety disorders. Blood oxygenation level dependent activation in response to negative image anticipation is also sensitive to anxiolytic treatment, suggesting that image anticipation probes anxiety systems. It is not clear, however, if behavioral responses to image anticipation are also sensitive to anxiolytics. This study tested the hypothesis that anxiety behaviors during anticipation of negative images are sensitive to anxiolytic treatment. METHOD: This study examined the effects of alprazolam and pregabalin treatment on potentiated startle during affective image anticipation. RESULTS: There was an effect of anticipation type (negative versus neutral versus positive) on startle reactivity and subjective ratings, suggesting that the task was effective in assaying negative anticipatory arousal. Both treatments significantly reduced overall startle magnitude. However, neither treatment specifically affected potentiated startle during aversive anticipation. CONCLUSION: These data suggest that potentiated startle in response to anticipation of aversive images is not sensitive to anxiolytic treatments in a healthy population, limiting its use as a predictive model of anxiolytic activity. This article is a US Government work and is in the public domain in the USA.


Subject(s)
Alprazolam/pharmacology , Anti-Anxiety Agents/pharmacology , Anticipation, Psychological/drug effects , Reflex, Startle/drug effects , gamma-Aminobutyric Acid/analogs & derivatives , Alprazolam/administration & dosage , Anti-Anxiety Agents/administration & dosage , Anxiety/drug therapy , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Male , Pregabalin , Young Adult , gamma-Aminobutyric Acid/administration & dosage , gamma-Aminobutyric Acid/pharmacology
13.
J Psychiatry Neurosci ; 37(6): 369-78, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22663947

ABSTRACT

Several lines of evidence suggest that deficits in γ-aminobutyric acid (GABA) inhibitory neurotransmission are implicated in the pathophysiology of schizophrenia, bipolar disorder, major depressive disorder and obsessive-compulsive disorder. Cortical inhibition refers to a neurophysiological process, whereby GABA inhibitory interneurons selectively attenuate pyramidal neurons. Transcranial magnetic stimulation (TMS) represents a noninvasive technique to measure cortical inhibition, excitability and plasticity in the cortex. These measures were traditionally specific to the motor cortex, which is an important limitation when nonmotor neurophysiological processes are of primary interest. Recently, TMS has been combined with electro encephalography (EEG) to derive such measurements directly from the cortex. This review focuses on neurophysiological studies related to inhibitory and excitatory TMS paradigms, linking dysfunctional GABAergic neurotransmission to disease states. We review evidence that suggests cortical inhibition deficits among psychiatric populations and demonstrate how each disorder has a specific neurophysiological response to treatment. We conclude by discussing the future directions of TMS combined with EEG, demonstrating the potential to identify biological markers of neuropsychiatric disorders.


Subject(s)
Cerebral Cortex/physiopathology , Mental Disorders/physiopathology , Nerve Net/physiopathology , Neural Inhibition/physiology , Transcranial Magnetic Stimulation/methods , Transcranial Magnetic Stimulation/trends , Cerebral Cortex/metabolism , Forecasting/methods , Humans , Mental Disorders/metabolism , Nerve Net/metabolism
14.
Front Hum Neurosci ; 6: 42, 2012.
Article in English | MEDLINE | ID: mdl-22470326

ABSTRACT

Pregabalin has shown promise in the treatment of anxiety disorders. Previous functional magnetic resonance imaging (fMRI) studies indicate agents used to treat anxiety, e.g., SSRIs and benzodiazepines, attenuate amygdala, insula, and medial prefrontal cortex (mPFC) activation during emotional processing. Our prior study has shown that during anticipation of an emotional stimulus, pregabalin attenuates amygdala and insula activation but increases medial PFC activation. In this study, we examined whether, similar to SSRIs and benzodiazepines, pregabalin attenuates amygdala, insula, and medial PFC during emotional face processing. Sixteen healthy volunteers underwent a double-blind within-subjects fMRI study investigating effects of placebo, 50 mg, and 200 mg pregabalin on neural activation during an emotional face-matching task. Linear mixed model analysis revealed that pregabalin dose-dependently attenuated left amygdala activation during fearful face-matching and left anterior insula activation during angry face-matching. The 50 mg dose exhibited more robust effects than the 200 mg dose in the right anterior insula and ventral ACC. Thus, pregabalin shares some similarity to SSRIs and benzodiazepines in attenuating anger and fear-related insula and amygdala activation during emotional face processing. However, there is evidence that a subclinical 50 mg dose of pregabalin produced more robust and widespread effects on neural responses in this paradigm than the more clinically relevant 200 mg dose. Taken together, pregabalin has a slightly different effect on brain activation as it relates to anticipation and emotional face processing, which may account for its unique characteristic as an agent for the treatment of anxiety disorders.

15.
Neuropsychopharmacology ; 37(5): 1144-51, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22169948

ABSTRACT

Several lines of evidence suggest that obsessive-compulsive disorder (OCD) is associated with an inability to inhibit unwanted intrusive thoughts. The neurophysiological mechanisms mediating such inhibitory deficits include abnormalities in cortical γ-aminobutyric acid (GABA) inhibitory as well as N-methyl-D-aspartate (NMDA) receptor-mediated mechanisms. Molecular evidence suggests that both these neurotransmitter systems are involved in OCD. Transcranial magnetic stimulation (TMS) represents a noninvasive technique to ascertain neurophysiological indices of inhibitory GABA and facilitatory NMDA receptor-mediated mechanisms. In this study, both mechanisms were indexed in 34 patients with OCD (23 unmedicated and 11 medicated) and compared with 34 healthy subjects. Cortical inhibitory and facilitatory neurotransmission was measured using TMS paradigms known as short-interval cortical inhibition (SICI), cortical silent period (CSP), and intracortical facilitation (ICF). Patients with OCD demonstrated significantly shortened CSP (p<0.001, Cohen's d=0.91) and increased ICF (p<0.009, Cohen's d=0.71) compared with healthy subjects. By contrast, there were no significant deficits in SICI. After excluding patients with OCD and comorbid major depressive disorder (MDD) from the analysis, these differences remained significant. Our findings suggest that OCD is associated with dysregulation in cortical inhibitory and facilitatory neurotransmission. Specifically, these findings suggest impairments in GABA(B) receptor-mediated and NMDA receptor-mediated neurotransmission. These findings are consistent with previously published genetic studies implicating GABA(B), and NMDA transporter and receptor genes in OCD. It is posited that dysregulation of such mechanisms may lead to the generation and persistence of intrusive thoughts that form the basis for this disorder.


Subject(s)
Cortical Spreading Depression/physiology , Evoked Potentials, Motor/physiology , Motor Cortex/physiopathology , Obsessive-Compulsive Disorder/pathology , Adult , Case-Control Studies , Chi-Square Distribution , Female , Humans , Male , Middle Aged , Personality Inventory , Psychiatric Status Rating Scales , Time Factors , Transcranial Magnetic Stimulation
16.
Neuropsychopharmacology ; 36(7): 1466-77, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21430645

ABSTRACT

Pregabalin (PGB) has shown potential as an anxiolytic for treatment of generalized and social anxiety disorder. PGB binds to voltage-dependent calcium channels, leading to upregulation of GABA inhibitory activity and reduction in the release of various neurotransmitters. Previous functional magnetic resonance imaging (fMRI) studies indicate that selective serotonin reuptake inhibitors and benzodiazepines attenuate amygdala, insula, and medial prefrontal cortex activation during anticipation and emotional processing in healthy controls. The aim of this study was to examine whether acute PGB administration would attenuate activation in these regions during emotional anticipation. In this double-blind, placebo-controlled, randomized crossover study, 16 healthy controls completed a paradigm involving anticipation of negative and positive affective images during fMRI approximately 1 h after administration of placebo, 50, or 200 mg PGB. Linear mixed model analysis revealed that PGB was associated with (1) decreases in left amygdala and anterior insula activation and (2) increases in anterior cingulate (ACC) activation, during anticipation of positive and negative stimuli. There was also a region of the anterior amygdala in which PGB dose was associated with increased activation during anticipation of negative and decreased activation during anticipation of positive stimuli. Attenuation of amygdala and insula activation during anticipatory or emotional processing may represent a common regional brain mechanism for anxiolytics across drug classes. PGB induced increases in ACC activation could be a unique effect related to top-down modulation of affective processing. These results provide further support for the viability of using pharmaco-fMRI to determine the anxiolytic potential of pharmacologic agents.


Subject(s)
Amygdala/drug effects , Analgesics/pharmacology , Attention/drug effects , Cerebral Cortex/drug effects , Emotions/drug effects , gamma-Aminobutyric Acid/analogs & derivatives , Adult , Amygdala/blood supply , Brain Mapping , Cerebral Cortex/blood supply , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/methods , Male , Oxygen/blood , Photic Stimulation/methods , Pregabalin , Young Adult , gamma-Aminobutyric Acid/pharmacology
17.
Psychopharmacol Bull ; 43(3): 15-25, 2010.
Article in English | MEDLINE | ID: mdl-21150843

ABSTRACT

OBJECTIVE: Sexual dysfunction is frequently associated with depression and is often exacerbated by antidepressant treatment. The true prevalence of antidepressant minduced dysfunction during a major depressive episode is generally underreported, due to reliance on spontaneous self-report data and the reluctance of physicians to use standardized rating scales. The aim of this study is to validate the Sex Effects scale (SexFX) in a healthy population, addressing internal and inter-rater reliability, test-retest reliability, as well as convergent and divergent validity. MATERIALS AND METHODS: The SexFX is a 13-item scale that assesses severity of sexual dysfunction across the domains of desire, arousal, and orgasm based on the frequency of behaviour. Healthy participants (N = 53) had the SexFX and Changes in Sexual Functioning Questionnaire (CSFQ) administered at two timepoints, two weeks apart. RESULTS: The Cronbach's a was 0.91 and 0.93 for the male and female scales, respectively, and inter-rater reliability was very high with ICCs of 0.99 for both the male and female scales. Concurrent validity with the CSFQ was adequate. CONCLUSION: The SexFX demonstrated satisfactory psychometric properties, providing the results necessary to proceed with further validation trials.


Subject(s)
Sexual Dysfunction, Physiological/diagnosis , Sexual Dysfunctions, Psychological/diagnosis , Surveys and Questionnaires , Adult , Female , Humans , Male , Middle Aged , Observer Variation , Ontario , Pilot Projects , Predictive Value of Tests , Psychometrics , Reference Values , Reproducibility of Results , Young Adult
18.
J Clin Psychiatry ; 71(7): 839-54, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20667290

ABSTRACT

Anxiety disorders, as a group, are among the most common mental health conditions and frequently cause significant functional impairment. Both psychotherapeutic and pharmacologic techniques are recognized to be effective management strategies. This review provides a discussion of the major classes of psychotropic medications investigated in clinical trials of the following anxiety disorders: panic disorder, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder, and obsessive-compulsive disorder. Findings suggest that both selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors are useful first-line agents for most of the anxiety disorders, particularly given the frequent comorbidity with mood disorders. Highly serotonergic agents are preferred for obsessive-compulsive disorder. Other antidepressants, such as tricyclic antidepressants or monoamine oxidase inhibitors, are generally reserved as second- and third-line strategies due to tolerability issues. Evidence for other agents, including anticonvulsants and atypical antipsychotics, suggests that they may have an adjunctive role to antidepressants in cases of treatment resistance, while azapirones have been used effectively for generalized anxiety disorder, and a substantial body of evidence supports benzodiazepine use in panic disorder and generalized anxiety disorder. Despite notable advances, many patients with anxiety disorders fail to adequately respond to existing pharmacologic treatments. Increased research attention should be focused on systematizing pharmacologic and combined pharmacologic-psychosocial strategies to address treatment resistance and developing novel treatments for anxiety disorders.


Subject(s)
Anxiety Disorders/drug therapy , Psychotropic Drugs/therapeutic use , Anticonvulsants/therapeutic use , Antidepressive Agents/therapeutic use , Antipsychotic Agents/therapeutic use , Anxiety Disorders/diagnosis , Anxiety Disorders/psychology , Benzodiazepines/therapeutic use , Buspirone/therapeutic use , Humans , Obsessive-Compulsive Disorder/drug therapy , Panic Disorder/drug therapy , Phobic Disorders/drug therapy , Randomized Controlled Trials as Topic , Stress Disorders, Post-Traumatic/drug therapy
19.
Curr Top Behav Neurosci ; 2: 505-25, 2010.
Article in English | MEDLINE | ID: mdl-21309124

ABSTRACT

Post-traumatic stress disorder (PTSD) is a prevalent psychiatric disorder that may result in significant social and occupational debilitation unless symptoms are recognized and treated appropriately. Considerable research effort has been devoted over the last 20 years to developing effective pharmacological treatments for this illness. At this time, the bulk of the agents investigated include antidepressants, anticonvulsants, atypical antipsychotics, benzodiazepines, and antiadrenergic agents. Herein, we review the existing evidence base for these different classes of psychotropics in PTSD. Emphasis is placed on discussion of evidence stemming from randomized placebo-controlled clinical trials wherever possible. A brief description of novel agents that have shown initial promise for PTSD treatment is also provided.


Subject(s)
Adrenergic Antagonists/therapeutic use , Anticonvulsants/therapeutic use , Antidepressive Agents/therapeutic use , Antipsychotic Agents/therapeutic use , Benzodiazepines/therapeutic use , Monoamine Oxidase Inhibitors/therapeutic use , Selective Serotonin Reuptake Inhibitors/therapeutic use , Stress Disorders, Post-Traumatic/drug therapy , Antidepressive Agents, Tricyclic , Benzodiazepines/adverse effects , Humans , Randomized Controlled Trials as Topic , Treatment Outcome
20.
J Sex Med ; 7(2 Pt 1): 816-25, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19796059

ABSTRACT

AIM: Men with Major Depressive Disorder (MDD) report high rates of sexual dysfunction, as do healthy males with low levels of testosterone. The objective of this study is to evaluate the effects of depression and low testosterone across various domains of sexual function. METHODS: Untreated depressed males (N = 44) and age-matched healthy controls (N = 50) had blood samples drawn to determine morning levels of total testosterone (TT) and bioavailable testosterone (BT). In addition, questionnaires regarding depressive symptoms as well as sexual function were administered. MAIN OUTCOME MEASURES: Sexual function outcomes were measured using the Sex Effects (SexFX) Scale and depression severity was assessed with the Hamilton Rating Scale for Depression-17 item (HAMD-17). RESULTS: Using TT criteria, 27.9% of men were categorically defined as hypogonadal compared to 19.3% using BT criteria. Within both TT and BT hypogonadal groups, men with MDD had lower scores on all domains of sexual function compared to healthy controls with hypogonadism. Testosterone levels interacted with MDD status to affect orgasm and desire, although not arousal. Multiple linear regression analyses revealed that depression status was the main factor influencing sexual function. Hypogonadal status was not a predictor of sexual function in this sample, although age did play a minor role in the domain of arousal. CONCLUSION: While testosterone levels appear to influence sexual function, specifically orgasm, the presence of MDD appears to be a stronger factor and has high predictive value for sexual outcomes.


Subject(s)
Depressive Disorder, Major/blood , Depressive Disorder, Major/psychology , Sexual Dysfunction, Physiological/blood , Sexual Dysfunction, Physiological/psychology , Sexual Dysfunctions, Psychological/blood , Sexual Dysfunctions, Psychological/psychology , Testosterone/blood , Adult , Arousal/physiology , Biological Availability , Comorbidity , Cross-Sectional Studies , Depressive Disorder, Major/epidemiology , Humans , Hypogonadism/blood , Hypogonadism/epidemiology , Hypogonadism/psychology , Libido/physiology , Male , Middle Aged , Orgasm/physiology , Risk Factors , Sex Hormone-Binding Globulin/metabolism , Sexual Dysfunction, Physiological/epidemiology , Sexual Dysfunctions, Psychological/epidemiology , Surveys and Questionnaires
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