Ketamine for Social Anxiety Disorder: A Randomized, Placebo-Controlled Crossover Trial.

Many patients with social anxiety disorder (SAD) experience inadequate symptom relief from available treatments. Ketamine is a potent N-methyl-D-aspartate receptor antagonist with a potentially novel mechanism of action for the treatment of anxiety disorders. Therefore, we conducted a double-blind, randomized, placebo-controlled crossover trial in 18 adults with DSM-5 SAD and compared the effects between intravenous ketamine (0.5 mg/kg over 40 min) and placebo (normal saline) on social phobia symptoms. Ketamine and placebo infusions were administered in a random order with a 28-day washout period between infusions. Ratings of anxiety were assessed 3-h post-infusion and followed for 14 days. We used linear mixed models to assess the impact of ketamine and placebo on anxiety symptoms. Outcomes were blinded ratings on the Liebowitz Social Anxiety Scale (LSAS) and self-reported anxiety on a visual analog scale (VAS-Anxiety). We also used the Wilcoxon signed-rank test to compare the proportion of treatment responders. Based on prior studies, we defined response as a greater than 35% LSAS reduction and 50% VAS-Anxiety reduction. We found ketamine resulted in a significantly greater reduction in anxiety relative to placebo on the LSAS (Time × Treatment: F9,115=2.6, p=0.01) but not the VAS-Anxiety (Time × Treatment: F10,141=0.4, p=0.95). Participants were significantly more likely to exhibit a treatment response after ketamine infusion relative to placebo in the first 2 weeks following infusion measured on the LSAS (33.33% response ketamine vs 0% response placebo, Wilcoxon signed-rank test z=2.24, p=0.025) and VAS (88.89% response ketamine vs 52.94% response placebo, Wilcoxon signed-rank test z=2.12, p=0.034). In conclusion, this proof-of-concept trial provides initial evidence that ketamine may be effective in reducing anxiety.

Risk of Irritability With Psychostimulant Treatment in Children With ADHD: A Meta-Analysis.

OBJECTIVE: Irritability is listed as a common side effect of psychostimulant medications. However, psychostimulants have been demonstrated as an effective treatment in reducing irritability and aggression in children with attention-deficit/hyperactivity disorder (ADHD). The goal of this study was to quantify the risk of irritability as a side effect of psychostimulant treatment for ADHD. DATA SOURCES AND STUDY SELECTION: A PubMed search was conducted on August 18, 2013, to identify all double-blind, randomized, placebo-controlled trials published in English examining the efficacy of psychostimulant medications in the treatment of children with ADHD. Trials were excluded if (1) they required additional psychiatric or medical comorbidity in addition to ADHD, (2) they involved fewer than 20 subjects (parallel group trials), or (3) children received psychostimulant medication for less than 1 week. DATA EXTRACTION: A fixed-effects meta-analysis was used to examine the risk ratio of irritability reported as a side effect in children treated with psychostimulants compared to placebo. Stratified subgroup analysis and meta-regression were used to examine the effects of stimulant type, dosage, duration of use, and trial design on the measured risk of irritability. RESULTS: From 92 potentially eligible trials, the meta-analysis identified 32 trials involving 3,664 children with ADHD that reported data on irritability as a side effect. The relative risk of irritability significantly differed between psychostimulant classes (test for subgroup differences χ²1 = 7.6, P = .006). Methylphenidate derivatives were associated with a significantly decreased risk of irritability compared to placebo (risk ratio [RR] = 0.89 [95% CI, 0.82 to 0.96], z = -2.87, P = .004, k = 32, I² = 50%), whereas amphetamine derivatives were associated with a significantly increased risk of irritability (RR = 2.90 [95% CI, 1.26 to 6.71], z = 2.5, P = .01, k = 5, I² = 0%). CONCLUSIONS: This meta-analysis suggests an increased risk of irritability may be confined to amphetamine-derived psychostimulants. Future meta-analyses examining the effects of amphetamine and methylphenidate derivatives on irritability as a continuous measure, as well as head-to-head trials between methylphenidate and amphetamine derivatives examining effects on irritability, will be important to replicate the findings of this meta-analysis.

The efficacy of benzodiazepines as acute anxiolytics in children: A meta-analysis.

OBJECTIVE: Current practice guidelines do not recommend benzodiazepines for acute management of anxiety disorders in pediatric patients. However, in procedural settings, benzodiazepines are commonly used to relieve acute preprocedural stress. This meta-analysis examines the efficacy and tolerability of benzodiazepines as short-term anxiolytics in children. METHOD: PubMed was searched for randomized controlled trials assessing the efficacy of benzodiazepines as short-term anxiolytics in pediatric patients. Twenty-one trials involving 1,416 participants were included. A fixed effects model was used to examine the standardized mean difference of improvement in anxiety levels compared to control conditions. In stratified subgroup and meta-regression, the effect of the specific agent, dose, timing, and setting of benzodiazepine treatment was examined. RESULTS: A significant benefit was seen for benzodiazepines compared to control (standardized mean difference = 0.71 [95% confidence interval, 0.60-0.82], k = 24, z = 12.7, P < .001). There was also funnel plot asymmetry in this meta-analysis, suggesting some evidence of publication bias. Moderator analyses found that when benzodiazepines were used in dental or nonoperating room procedures, they were more effective than when they were used in operating room procedures (test for subgroup differences Q2 = 6.34, P = .04). Tolerability analysis revealed there was no significant difference in the risk of developing irritability or behavioral changes between benzodiazepine and control groups. CONCLUSIONS: Benzodiazepines are effective and well-tolerated when used as short-term anxiolytics in procedural settings for pediatric patients. Further research is needed to determine whether benzodiazepines are effective in pediatric anxiety disorders.

N-Acetylcysteine in the Treatment of Pediatric Tourette Syndrome: Randomized, Double-Blind, Placebo-Controlled Add-On Trial.

BACKGROUND: Current pharmacological treatments for Tourette Syndrome (TS), such as antipsychotic agents and α-2 agonists, are moderately effective in the treatment of tics, but have substantial side effects that limit their use. N-acetylcysteine (NAC) modulates glutamatergic systems, and has been used safely as an antioxidant agent with minimal side effects for decades. NAC has been increasingly studied for the treatment of other obsessive-compulsive spectrum disorders. We aim to examine the efficacy of NAC for the treatment of pediatric TS in a double-blind, placebo-controlled, add-on study. METHODS: Thirty-one children and adolescents 8-17 years of age with TS were randomly assigned to receive NAC or matching placebo for 12 weeks. Our primary outcome was change in severity of tics as measured by the Yale Global Tic Severity Scale (YGTSS), Total tic score. Secondary measures assessed comorbid obsessive-compulsive disorder (OCD), depression, anxiety, and attention-deficit/hyperactivity disorder (ADHD). Linear mixed models in SAS were used to examine differences between NAC and placebo. RESULTS: Of 31 randomized subjects, 14 were assigned to placebo (two females; 11.5 + 2.8 years) and 17 to active NAC (five females; 12.4 + 1.4 years) treatment. No significant difference between NAC and placebo was found in reducing tic severity or any secondary outcomes. CONCLUSIONS: We found no evidence for efficacy of NAC in treating tic symptoms. Our findings stand in contrast to studies suggesting benefits of NAC in the treatment of other obsessive-compulsive spectrum disorders in adults, including OCD and trichotillomania, but are similar to a recent placebo-controlled trial of pediatric trichotillomania that found no benefit of NAC.

Meta-Analysis: Reduced Risk of Anxiety with Psychostimulant Treatment in Children with Attention-Deficit/Hyperactivity Disorder.

OBJECTIVE: Anxiety is a commonly reported side-effect of psychostimulant treatment. Our goal was to quantify the risk of anxiety as a side effect of psychostimulant treatment for attention-deficit/hyperactivity disorder (ADHD). METHODS: We conducted a PubMed search to identify all double-blind, randomized, placebo-controlled trials examining the efficacy of psychostimulant medications in the treatment of children with ADHD. We used a fixed-effects meta-analysis to examine the risk ratio of anxiety reported as a side effect in children treated with psychostimulants compared with those treated with placebo. We used stratified subgroup analysis and meta-regression to examine the effects of stimulant type, dosage, duration of use, and trial design on the measured risk of anxiety. RESULTS: We identified 23 studies involving 2959 children with ADHD for inclusion in our meta-analysis. The risk of anxiety associated with psychostimulant treatment was significantly lower than that experienced with placebo (relative risk [RR] = 0.86 [95% CI: 0.77, 0.95], z = -2.90, p < 0.05). Higher doses of psychostimulants were associated with a reduced measured risk of anxiety of psychostimulants when compared with placebo (ß = -0.0039 [95% CI: -0.00718, -0.00064], z = -2.34, p = 0.019). CONCLUSIONS: Meta-analysis suggests that treatment with psychostimulants significantly reduced the risk of anxiety when compared with placebo. This finding does not rule out the possibility that some children experience increased anxiety when treated with psychostimulants, but suggests that those risks are outweighed by the number of children who experience improvement in anxiety symptoms (possibly as a secondary effect of improved control of ADHD symptoms). Clinicians should consider rechallenging children with ADHD who report new-onset or worsening anxiety with psychostimulants, as these symptoms are much more likely to be coincidental rather than caused by psychostimulants.

Meta-Analysis: Risk of Tics Associated With Psychostimulant Use in Randomized, Placebo-Controlled Trials.

OBJECTIVE: Clinical practice currently restricts the use of psychostimulant medications in children with tics or a family history of tics for fear that tics will develop or worsen as a side effect of treatment. Our goal was to conduct a meta-analysis to examine the risk of new onset or worsening of tics as an adverse event of psychostimulants in randomized, placebo-controlled trials. METHOD: We conducted a PubMed search to identify all double-blind, randomized, placebo-controlled trials examining the efficacy of psychostimulant medications in the treatment of children with attention-deficit/hyperactivity disorder (ADHD). We used a fixed effects meta-analysis with risk ratio of new onset or worsening tics in children treated with psychostimulants compared to placebo. We used stratified subgroup analysis and meta-regression to examine the effects of stimulant type, dose, duration of treatment, recorder of side effect data, trial design, and mean age of participants on the measured risk of tics. RESULTS: We identified 22 studies involving 2,385 children with ADHD for inclusion in our meta-analysis. New onset tics or worsening of tic symptoms were commonly reported in the psychostimulant (event rate = 5.7%, 95% CI = 3.7%-8.6%) and placebo groups (event rate = 6.5%, 95% CI = 4.4%-9.5%). The risk of new onset or worsening of tics associated with psychostimulant treatment was similar to that observed with placebo (risk ratio = 0.99, 95% CI = 0.78-1.27, z = -0.05, p = .962). Type of psychostimulant, dose, duration of treatment, recorder, and participant age did not affect risk of new onset or worsening of tics. Crossover studies were associated with a significantly greater measured risk of tics with psychostimulant use compared to parallel group trials. CONCLUSION: Meta-analysis of controlled trials does not support an association between new onset or worsening of tics and psychostimulant use. Clinicians may want to consider rechallenging children who report new onset or worsening of tics with psychostimulant use, as these symptoms are much more likely to be coincidental rather than caused by psychostimulants.

LONG-TERM OUTCOME IN PEDIATRIC TRICHOTILLOMANIA.

OBJECTIVE: To examine long-term outcome in children with trichotillomania. METHOD: We conducted follow-up clinical assessments an average of 2.8 ± 0.8 years after baseline evaluation in 30 of 39 children who previously participated in a randomized, double-blind, placebo-controlled trial of N-acetylcysteine (NAC) for pediatric trichotillomania. Our primary outcome was change in hairpulling severity on the Massachusetts General Hospital Hairpulling Hospital Hairpulling Scale (MGH-HPS) between the end of the acute phase and follow-up evaluation. We also obtained secondary measures examining styles of hairpulling, comorbid anxiety and depressive symptoms, as well as continued treatment utilization. We examined both correlates and predictors of outcome (change in MGH-HPS score) using linear regression. RESULTS: None of the participants continued to take NAC at the time of follow-up assessment. No significant changes in hairpulling severity were reported over the follow-up period. Subjects reported significantly increased anxiety and depressive symptoms but improvement in automatic pulling symptoms. Increased hairpulling symptoms during the follow-up period were associated with increased depression and anxiety symptoms and increased focused pulling. Older age and greater focused pulling at baseline assessment were associated with poor long-term prognosis. CONCLUSIONS: Our findings suggest that few children with trichotillomania experience a significant improvement in trichotillomania symptoms if behavioral treatments are inaccessible or have failed to produce adequate symptom relief. Our findings also confirm results of previous cross-sectional studies that suggest an increased risk of depression and anxiety symptoms with age in pediatric trichotillomania. Increased focused pulling and older age among children with trichotillomania symptoms may be associated with poorer long-term prognosis.

Meta-analysis: parental interventions for preschool ADHD.

OBJECTIVE: Although psychostimulants are commonly utilized to treat preschoolers with ADHD, side effects and parental preferences limit their use in younger children. The current meta-analysis examines the efficacy of parent interventions for the treatment of ADHD in preschoolers. METHOD: We searched PubMed and the Cochrane Library for randomized, controlled trials comparing behavioral interventions for preschool children with ADHD. Our primary outcome measure was mean improvement in an ADHD rating scale compared with control conditions. RESULTS: Eight trials were included in the final analysis, totaling 399 participants. There was a significant benefit of parental behavioral interventions compared with control conditions (standardized mean difference [SMD] = 0.61, 95% confidence interval = [0.40, 0.83], z = 5.6, p < .001). CONCLUSION: The present meta-analysis provides preliminary evidence that parental interventions are an efficacious treatment for preschool ADHD. Future research is needed to compare the relative efficacy of parental interventions for ADHD with medication management and to determine if the combination of parental training and medication management is more effective than either condition alone.

Nutritional supplements for the treatment of ADHD.

Polyunsaturated fatty acid supplementation appears to have modest benefit for improving ADHD symptoms. Melatonin appears to be effective in treating chronic insomnia in children with ADHD but appears to have minimal effects in reducing core ADHD symptoms. Many other natural supplements are widely used in the United States despite minimal evidence of efficacy and possible side effects. This review synthesizes and evaluates the scientific evidence regarding the potential efficacy and side effects of natural supplements and herbal remedies for ADHD. We provide clinicians with recommendations regarding their potential use and role in overall ADHD treatment.