Ketamine for rapid reduction of suicidal ideation: a randomized controlled trial.

BACKGROUND: Suicide is a devastating public health problem and very few biological treatments have been found to be effective for quickly reducing the intensity of suicidal ideation (SI). We have previously shown that a single dose of ketamine, a glutamate N-methyl-d-aspartate (NMDA) receptor antagonist, is associated with a rapid reduction in depressive symptom severity and SI in patients with treatment-resistant depression. METHOD: We conducted a randomized, controlled trial of ketamine in patients with mood and anxiety spectrum disorders who presented with clinically significant SI (n = 24). Patients received a single infusion of ketamine or midazolam (as an active placebo) in addition to standard of care. SI measured using the Beck Scale for Suicidal Ideation (BSI) 24 h post-treatment represented the primary outcome. Secondary outcomes included the Montgomery-Asberg Depression Rating Scale--Suicidal Ideation (MADRS-SI) score at 24 h and additional measures beyond the 24-h time-point. RESULTS: The intervention was well tolerated and no dropouts occurred during the primary 7-day assessment period. BSI score was not different between the treatment groups at 24 h (p = 0.32); however, a significant difference emerged at 48 h (p = 0.047). MADRS-SI score was lower in the ketamine group compared to midazolam group at 24 h (p = 0.05). The treatment effect was no longer significant at the end of the 7-day assessment period. CONCLUSIONS: The current findings provide initial support for the safety and tolerability of ketamine as an intervention for SI in patients who are at elevated risk for suicidal behavior. Larger, well-powered studies are warranted.

Deep brain stimulation of the ventral internal capsule/ventral striatum for obsessive-compulsive disorder: worldwide experience.

Psychiatric neurosurgery teams in the United States and Europe have studied deep brain stimulation (DBS) of the ventral anterior limb of the internal capsule and adjacent ventral striatum (VC/VS) for severe and highly treatment-resistant obsessive-compulsive disorder. Four groups have collaborated most closely, in small-scale studies, over the past 8 years. First to begin was Leuven/Antwerp, followed by Butler Hospital/Brown Medical School, the Cleveland Clinic and most recently the University of Florida. These centers used comparable patient selection criteria and surgical targeting. Targeting, but not selection, evolved during this period. Here, we present combined long-term results of those studies, which reveal clinically significant symptom reductions and functional improvement in about two-thirds of patients. DBS was well tolerated overall and adverse effects were overwhelmingly transient. Results generally improved for patients implanted more recently, suggesting a 'learning curve' both within and across centers. This is well known from the development of DBS for movement disorders. The main factor accounting for these gains appears to be the refinement of the implantation site. Initially, an anterior-posterior location based on anterior capsulotomy lesions was used. In an attempt to improve results, more posterior sites were investigated resulting in the current target, at the junction of the anterior capsule, anterior commissure and posterior ventral striatum. Clinical results suggest that neural networks relevant to therapeutic improvement might be modulated more effectively at a more posterior target. Taken together, these data show that the procedure can be successfully implemented by dedicated interdisciplinary teams, and support its therapeutic promise.

NeuroDAC: an open-source arbitrary biosignal waveform generator.

Objective.Researchers are developing biomedical devices with embedded closed-loop algorithms for providing advanced adaptive therapies. As these devices become more capable and algorithms become more complex, tasked with integrating and interpreting multi-channel, multi-modal electrophysiological signals, there is a need for flexible bench-top testing and prototyping. We present a methodology for leveraging off-the-shelf audio equipment to construct a biosignal waveform generator capable of streaming pre-recorded biosignals from a host computer. By re-playing known, well-characterized, but physiologically relevant real-world biosignals into a device under test, researchers can evaluate their systems without the need for expensivein vivoexperiments.Approach.An open-source design based on the proposed methodology is described and validated, the NeuroDAC. NeuroDAC allows for 8 independent channels of biosignal playback using a simple, custom designed attenuation and buffering circuit. Applications can communicate with the device over a USB interface using standard audio drivers. On-board analog amplitude adjustment is used to maximize the dynamic range for a given signal and can be independently tuned for each channel.Main results.Low noise component selection yields a no-signal noise floor of just 5.35 ± 0.063. NeuroDAC's frequency response is characterized with a high pass -3 dB rolloff at 0.57 Hz, and is capable of accurately reproducing a wide assortment of biosignals ranging from EMG, EEG, and ECG to extracellularly recorded neural activity. We also present an application example using the device to test embedded algorithms on a closed-loop neural modulation device, the Medtronic RC+S.Significance.By making the design of NeuroDAC open-source we aim to present an accessible tool for rapidly prototyping new biomedical devices and algorithms than can be easily modified based on individual testing needs.ClinicalTrials.gov Identifiers: NCT04281134, NCT03437928, NCT03582891.

Symptom dimensions and cognitive-behavioural therapy outcome for pediatric obsessive-compulsive disorder.

OBJECTIVE: To examine whether obsessive-compulsive disorder (OCD) symptom subtypes are associated with response rates to cognitive-behavioural therapy (CBT) among pediatric patients. METHOD: Ninety-two children and adolescents with OCD (range = 7-19 years) received 14 sessions of weekly or intensive (daily psychotherapy sessions) family-based CBT. Assessments were conducted at baseline and post-treatment. Primary outcomes included scores on the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS), remission status, and ratings on the Clinical Global Improvement (CGI) and Clinical Global Impression - Severity (CGI-Severity) scales. RESULTS: Seventy-six per cent of study participants (n = 70) were classified as treatment responders. Patients with aggressive/checking symptoms at baseline showed a trend (P = 0.06) toward improved treatment response and exhibited greater pre/post-treatment CGI-Severity change than those who endorsed only non-aggressive/checking symptoms. Step-wise linear regression analysis indicated higher scores on the aggressive/checking dimension were predictive of treatment-related change in the CGI-Severity index. Regression analysis with CY-BOCS score as the dependent variable showed no difference between OCD subtypes. CONCLUSION: Response to CBT in pediatric OCD patients does not differ substantially across subtypes.

Carbon dioxide sensitivity in panic anxiety. Ventilatory and anxiogenic response to carbon dioxide in healthy subjects and patients with panic anxiety before and after alprazolam treatment.

One hypothesis that could account for the anxiogenic response to breathing air supplemented with carbon dioxide seen in panic anxiety patients is that panic patients might have abnormally high central medullary chemoreceptor sensitivity. Chemoreceptor sensitivity was assessed by using a rebreathing technique to measure the ventilatory response to CO2 in 14 medication-free patients with agoraphobia and panic attacks and 23 healthy subjects. Ventilatory response to CO2 was similar in patients and controls (mean +/- SEM, 1.58 +/- 0.16 vs 1.58 +/- 0.14 L/min/mm Hg), suggesting that abnormal chemoreceptor sensitivity does not explain the behavioral sensitivity of panic patients to CO2. Anxiety ratings increased markedly during rebreathing both in patients and controls; anxiety increases were significantly greater in patients than in healthy subjects matched for age, sex, and rebreathing duration. Alprazolam treatment in eight patients markedly attenuated anxiety increases during rebreathing. Differences in anxiogenic sensitivity to CO2 between patients and controls may be due to differences in the regulation of noradrenergic or other neuronal systems.

Carbon dioxide-induced anxiety. Behavioral, physiologic, and biochemical effects of carbon dioxide in patients with panic disorders and healthy subjects.

Carbon dioxide was administered for 15 minutes to patients with panic disorders (5% CO2, n = 14) and healthy subjects (5% CO2, n = 11; 7.5% CO2, n = 8). Following administration of CO2 and air placebo, changes in behavioral ratings, vital signs, and plasma levels of the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol, cortisol, growth hormone, and prolactin were measured over three hours. In the healthy subjects, CO2 produced dose-related increases in anxiety, somatic symptoms, vital signs, and plasma cortisol levels. In the patients, the frequency of panic attacks (in eight of 14 patients) and the increases in anxiety and somatic symptoms induced by 5% CO2 exceeded those in the healthy subjects and were similar to those induced by 7.5% CO2 in the healthy subjects. The physiologic and biochemical measurements obtained did not elucidate the mechanisms underlying CO2-induced anxiety or the greater anxiogenic effects of CO2 seen in patients with panic disorders.

Serotonin function in obsessive-compulsive disorder. A comparison of the effects of tryptophan and m-chlorophenylpiperazine in patients and healthy subjects.

To evaluate the role of serotonin (5-HT) function in obsessive-compulsive disorder (OCD), behavioral and biochemical responses to the 5-HT receptor agonist m-chlorophenylpiperazine (MCPP) and the 5-HT precursor tryptophan were examined in healthy subjects and patients with OCD. Baseline prolactin levels and the prolactin rise following MCPP were significantly reduced in female patients compared with female healthy subjects. In contrast, the increase in prolactin level following tryptophan administration was not significantly different between male or female patients with OCD and the respective sex-matched healthy subjects. The prolactin responses to MCPP and tryptophan were both significantly higher in female patients and healthy subjects than in their male counterparts. The cortisol and growth hormone responses to MCPP and tryptophan were similar in the patients and healthy subjects and were not related to gender. The behavioral responses to MCPP or tryptophan were not consistently different between patients and healthy subjects, and neither MCPP nor tryptophan had effects on obsessive or compulsive symptoms. These results lend only partial support to the hypothesis that 5-HT dysfunction may be linked to the pathophysiology of OCD and point to the need for the evaluation of other neurotransmitter systems in future investigations of OCD.

The Yale-Brown Obsessive Compulsive Scale. II. Validity.

The development design and reliability of the Yale-Brown Obsessive Compulsive Scale have been described elsewhere. We focused on the validity of the Yale-Brown Scale and its sensitivity to change. Convergent and discriminant validity were examined in baseline ratings from three cohorts of patients with obsessive-compulsive disorder (N = 81). The total Yale-Brown Scale score was significantly correlated with two of three independent measures of obsessive-compulsive disorder and weakly correlated with measures of depression and of anxiety in patients with obsessive-compulsive disorder with minimal secondary depressive symptoms. Results from a previously reported placebo-controlled trial of fluvoxamine in 42 patients with obsessive-compulsive disorder showed that the Yale-Brown Scale was sensitive to drug-induced changes and that reductions in Yale-Brown Scale scores specifically reflected improvement in obsessive-compulsive disorder symptoms. Together, these studies indicate that the 10-item Yale-Brown Scale is a reliable and valid instrument for assessing obsessive-compulsive disorder symptom severity and that it is suitable as an outcome measure in drug trials of obsessive-compulsive disorder.

Efficacy of fluvoxamine in obsessive-compulsive disorder. A double-blind comparison with placebo.

A six- to eight-week double-blind placebo-controlled trial of the potent and selective serotonin reuptake inhibitor fluvoxamine was conducted in 42 patients with primary obsessive-compulsive disorder (OCD). Approximately one half of the patients also had symptoms of major depression. Fluvoxamine was significantly better than placebo on all measures of obsessive-compulsive symptoms. Nine of 21 patients were responders ("much improved") with fluvoxamine compared with no responders with placebo, and fluvoxamine was effective in patients with OCD both with and without secondary depression. Response of OCD was not correlated with severity of baseline depression. These data lend partial support to the serotonin hypothesis of OCD. However, since a number of patients failed to respond to fluvoxamine, the role of other neurochemical systems in this disorder needs to be explored.

The Yale-Brown Obsessive Compulsive Scale. I. Development, use, and reliability.

The Yale-Brown Obsessive Compulsive Scale was designed to remedy the problems of existing rating scales by providing a specific measure of the severity of symptoms of obsessive-compulsive disorder that is not influenced by the type of obsessions or compulsions present. The scale is a clinician-rated, 10-item scale, each item rated from 0 (no symptoms) to 4 (extreme symptoms) (total range, 0 to 40), with separate subtotals for severity of obsessions and compulsions. In a study involving four raters and 40 patients with obsessive-compulsive disorder at various stages of treatment, interrater reliability for the total Yale-Brown Scale score and each of the 10 individual items was excellent, with a high degree of internal consistency among all item scores demonstrated with Cronbach's alpha coefficient. Based on pretreatment assessment of 42 patients with obsessive-compulsive disorder, each item was frequently endorsed and measured across a range of severity. These findings suggest that the Yale-Brown Scale is a reliable instrument for measuring the severity of illness in patients with obsessive-compulsive disorder with a range of severity and types of obsessive-compulsive symptoms.

Specificity of serotonin reuptake inhibitors in the treatment of obsessive-compulsive disorder. Comparison of fluvoxamine and desipramine.

To evaluate whether serotonin reuptake inhibition is critical to the treatment of obsessive-compulsive disorder, 40 outpatients with a principal diagnosis of obsessive-compulsive disorder were randomized in a double-blind fashion to 8 weeks of treatment with either the serotonin reuptake inhibitor fluvoxamine maleate (n = 21) or the norepinephrine reuptake inhibitor desipramine hydrochloride (n = 19). Fluvoxamine was significantly better than desipramine in reducing the severity of obsessive-compulsive symptoms, as measured by the Yale-Brown Obsessive Compulsive Scale and by the global response rate ("responder" equaling "much improved"). Eleven of 21 patients were responders with fluvoxamine compared with 2 of 19 patients with desipramine. Fluvoxamine, but not desipramine, was also effective in reducing the severity of "secondary" depression. Fluvoxamine-induced improvement in symptoms of obsessive-compulsive disorder was not correlated with the severity of baseline depressive symptoms. This study provides additional evidence that the acute serotonin reuptake properties of a drug are predictive of its anti-obsessive-compulsive efficacy. It is hypothesized that the mechanism of action of serotonin reuptake inhibitors in obsessive-compulsive disorder may be related to chronic treatment-induced adaptive changes in presynaptic serotonin receptor function (eg, autoreceptor desensitization) and/or indirect influences on dopaminergic function (eg, in the basal ganglia).

Haloperidol addition in fluvoxamine-refractory obsessive-compulsive disorder. A double-blind, placebo-controlled study in patients with and without tics.

BACKGROUND: To determine the efficacy of adding haloperidol to the treatment of patients with obsessive-compulsive disorder (OCD), with or without a comorbid chronic tic disorder, who were refractory to adequate treatment with the serotonin-uptake inhibitor fluvoxamine alone. It was hypothesized that OCD patients with a concurrent chronic tic disorder would preferentially respond to this treatment. METHODS: Sixty-two patients with a primary DSM-III-R diagnosis of OCD received placebo fluvoxamine for 1 week, followed by 8 weeks of active fluvoxamine. Thirty-four of these patients were refractory to fluvoxamine and were randomized in a double-blind fashion to 4 weeks of treatment with either haloperidol (n = 17) or placebo (n = 17) added to ongoing fluvoxamine treatment. The placebo-treated group included five women and 12 men, six inpatients and 11 outpatients, and eight patients with a comorbid chronic tic disorder. The haloperidol-treated group consisted of two women and 15 men, three inpatients and 14 outpatients, and seven patients with a comorbid chronic tic disorder. All 34 patients completed the entire study. The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the Clinical Global Impression scale were the principal measures of treatment outcome. RESULTS: Haloperidol addition was significantly better than placebo in reducing the severity of obsessive-compulsive symptoms as measured by the Y-BOCS. Eleven of 17 patients responded to the haloperidol, compared with none of 17 patients given placebo. Eight of eight patients with comorbid chronic tic disorders, such as Tourette's disorder, responded to double-blind haloperidol addition to ongoing fluvoxamine treatment. Haloperidol addition was of little benefit in treating OCD patients without tics. Fluvoxamine blood levels were not related to treatment response. CONCLUSIONS: The results of this study suggest that OCD patients with a comorbid chronic tic disorder constitute a clinically meaningful subtype of OCD that might require conjoint serotonin-uptake inhibitor/neuroleptic therapy for effective symptom reduction.

Tryptophan depletion in patients with obsessive-compulsive disorder who respond to serotonin reuptake inhibitors.

METHODS: The effects of short-term tryptophan depletion were examined in 15 patients with DSM-III-R obsessive-compulsive disorder who had demonstrated symptom reduction following treatment with serotonin reuptake inhibitors. Patients received a 24-hour, low-tryptophan (160-mg/d) diet followed the next morning by a drink of 15 amino acids. A double-blind, placebo-controlled cross-over design was used. RESULTS: The diet and the amino acid drink reduced free plasma tryptophan levels by a mean of 84% 5 hours later. Short-term tryptophan depletion did not significantly change mean ratings of obsessions and compulsions. In contrast, mean depression ratings were significantly increased with tryptophan depletion compared with the control (tryptophan-supplemented) testing. CONCLUSION: Maintenance of serotonin reuptake inhibitor-induced improvement of obsessive and compulsive symptoms, unlike remission of depressive symptoms, may not depend on ongoing short-term availability of serotonin.

Elevated cerebrospinal fluid levels of oxytocin in obsessive-compulsive disorder. Comparison with Tourette's syndrome and healthy controls.

BACKGROUND: Limited neurobiological data have implicated central arginine vasopressin in the pathobiology of obsessive-compulsive disorder (OCD). Based on twin, family genetic, and pharmacological studies, some forms of OCD are etiologically related to Tourette's syndrome. The role of arginine vasopressin and related compounds such as oxytocin in Tourette's syndrome has not been previously explored. METHODS: To compare cerebrospinal fluid (CSF) levels of arginine vasopressin and oxytocin, we collected CSF at midday in a standardized fashion from a total of 83 individuals (29 patients with OCD, 23 patients with Tourette's syndrome, and 31 normal controls). We also collected family study data on each subject to determine which subjects had a family history positive for Tourette's syndrome, OCD, or related syndromes. RESULTS: In contrast to previous reports, we report similar concentrations of arginine vasopressin for all three groups but increased oxytocin levels in patients with OCD. Remarkably, this increase was observed only in a subset of patients with OCD (n = 22) independently identified as being without a personal or family history of tic disorders (P = .0003). In this subgroup of patients, the CSF oxytocin level was correlated with current severity of OCD (n = 19, r = .47, P < .05). CONCLUSIONS: A possible role for oxytocin in the neurobiology of a subtype of OCD is suggested by the elevated CSF levels of oxytocin and by the correlation between CSF oxytocin levels and OCD severity. These findings reinforce the value of family genetic data in identifying biologically homogeneous (and perhaps more etiologically homogeneous) groups of patients with OCD. Together with emerging pharmacological data showing differential responsiveness to treatment of tic-related OCD vs non-tic-related OCD, these data also argue strongly for the incorporation of tic-relatedness as a variable in biological and behavioral studies of patients with OCD.

Cerebral laterality, perception of emotion, and treatment response in obsessive-compulsive disorder.

Patients with obsessive-compulsive disorder (OCD) had lower right-ear advantages than healthy controls on five different language-related dichotic listening tests of cerebral laterality. This abnormality was more pronounced in patients with more severe illness. Stimulus pairs in one test consisted of one word with a positive emotional valence and one emotionally neutral word. Pairs in another test consisted of one negative and one neutral word. Patients with OCD tended to hear fewer emotion-related words than did healthy controls, a finding also noted in depressed patients. Moreover, OCD patients who responded to treatment with serotonin reuptake inhibitors heard fewer emotion-related words than did nonresponders.

On defining Sydenham's chorea: where do we draw the line?

Sydenham's chorea (SC) is a major manifestation of rheumatic fever characterized by an array of neuropsychiatric symptoms that vary in severity, timing, and character. Some of the same symptoms are seen in Tourette's syndrome and childhood-onset obsessive-compulsive disorder. Genetic vulnerability appears to play a role in all three conditions. The term PANDAS (pediatric autoimmune neuropsychiatric disorder associated with streptococcus) has been introduced to describe a putative subset of obsessive-compulsive disorder and Tourette's syndrome that bears some resemblance to Sydenham's chorea. This article discusses whether PANDAS should be subsumed under Sydenham's chorea, thus expanding the diagnostic boundaries of Sydenham's chorea to include primarily neuropsychiatric presentations now classified as cases of obsessive-compulsive disorder or Tourette's syndrome. We conclude that PANDAS is a useful construct, but that it would be premature to view it as a subset of Sydenham's chorea-whether defined narrowly or broadly.

Effects of tryptophan depletion on responses to yohimbine in healthy human subjects.

There is considerable evidence that both the norepinephrine (NE) and serotonin (5-HT) systems are involved in the regulation of human anxiety and fear responses. To assess the modulating effects of central 5-HT levels on NE function, 11 healthy human subjects were studied with placebo-controlled challenge tests involving tryptophan depletion followed by administration of the alpha-2-adrenergic antagonist yohimbine 0.4 mg/kg IV. Five of the 11 subjects reported a marked increase in feelings of nervousness (> or = 25 mm on a 100 mm analog scale) following the combination test, while 1/11 had this response to yohimbine alone. No subjects had an increase in nervousness during other control tests. The increase in nervousness after the tryptophan depletion-yohimbine test was statistically significant for the whole group, but there were no other unique changes in behavioral, physiologic or biochemical (MHPG, cortisol) variables with this test. These data are discussed in terms of possible functional interactions between the 5-HT and NE neurotransmitter systems.

m-Chlorophenylpiperazine in patients with obsessive-compulsive disorder: absence of symptom exacerbation.

Oral administration of the serotonin mixed agonist-antagonist meta-chlorophenylpiperazine (mCPP) at 0.5 mg/kg has been reported to exacerbate symptoms of obsessive-compulsive disorder (OCD). In an attempt to replicate these findings, double-blind behavioral and biochemical measures were obtained in 12 drug-free patients (9 men, 3 women) with OCD who received either oral mCPP (0.5 mg/kg), intravenous (IV) mCPP (0.1 mg/kg over 20 min), or placebo in random order on 3 separate test days. Neither oral nor IV mCPP had significant effects on the severity of OCD symptoms. The magnitude of the mCPP-induced plasma prolactin response and plasma mCPP levels were similar to those values obtained in other published studies in which mCPP exacerbated OCD symptoms. In contrast, both oral and IV mCPP were associated with significant increases in ratings of anxiety. These findings suggest that mCPP, whether administered by an oral or intravenous route (as a slow infusion), may not be a reliable probe for investigating obsessive-compulsive symptoms. It is possible, however, that more reproducible behavioral findings might be obtained by identifying susceptible subgroups of OCD or by including a behavioral exposure condition.

Effects of left frontal transcranial magnetic stimulation on depressed mood, cognition, and corticomotor threshold.

BACKGROUND: The pathophysiology of depression may include synaptic hypoactivity of left prefrontal cortex. Several groups of investigators have described improved mood associated with rapid transcranial magnetic stimulation (rTMS) but have not looked for possible cognitive side effects associated with left prefrontal magnetic stimulation. METHODS: We measured the effects of left prefrontal rTMS on mood, cognition, and motor evoked potential threshold in 10 patients with medication-resistant major depression. RESULTS: In a 2-week open trial of left prefrontal rTMS off antidepressant medications, scores on the Hamilton Rating Scale for Depression and the Beck Depression Inventory decreased by 41% and 40%, respectively. After resuming pre-rTMS antidepressant medication, improvement in mood was still significant at 1 and 3 months later. rTMS had no adverse effects on neuropsychological performance. rTMS treatments were associated with significant decreases in motor evoked potential threshold in the 9 of 10 patients who remained off psychotropic medications during the 2-week treatment period. CONCLUSIONS: These preliminary data suggest that left prefrontal rTMS is safe and improves mood in patients with medication-resistant major depression. Changes in motor evoked potential threshold suggest that prefrontal rTMS may alter brain activity at sites remote from the stimulation. Double-blind, sham-controlled studies are needed.

Neurobiological mechanisms of panic anxiety: biochemical and behavioral correlates of yohimbine-induced panic attacks.

The effects of yohimbine, an alpha 2-adrenergic receptor antagonist, on anxiety, blood pressure, heart rate, and plasma levels of the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol (MHPG) and cortisol were determined in 20 healthy subjects and 68 patients who had agoraphobia with panic attacks or panic disorder. Yohimbine produced panic attacks meeting DSM-III criteria in 37 patients and one healthy subject. The patients reporting yohimbine-induced panic attacks had significantly larger increases in plasma MHPG, cortisol, systolic blood pressure, and heart rate than the healthy subjects. These findings support the hypothesis relating high noradrenergic neuronal activity to the pathophysiology of panic attacks in a subgroup of panic disorder patients.