Improvement of psychic and somatic symptoms in adult patients with generalized anxiety disorder: examination from a duloxetine, venlafaxine extended-release and placebo-controlled trial

Meta-analysis of the comparative efficacy of benzodiazepines and antidepressants for psychic versus somatic symptoms of generalized anxiety disorder

BACKGROUND

Benzodiazepines and antidepressants are effective agents for the treatment of generalized anxiety disorder (GAD), with the HAM-A frequently used as a primary outcome measure. The GAD literature is inconsistent regarding which medications are more effective for somatic versus psychic symptoms of GAD, and treatment guidelines do not advocate for prescribing based on subtype. This meta-analysis aimed to determine whether benzodiazepines and antidepressants have a differential impact on the somatic versus psychic subscales of the HAM-A in GAD.

METHODS

An electronic search was undertaken for randomized controlled trials of either benzodiazepines or antidepressants for GAD that reported treatment response using the HAM-A subscales. Data were extracted by independent reviewers. A random effects assessment of weighted mean difference with 95% confidence intervals and subgroup difference was applied. All analysis was done on SPSS 26. An assessment of bias, and of quality of evidence was performed.

RESULTS

24 randomized controlled trials met the inclusion criteria: 18 antidepressant trials, 5 benzodiazepine trials and 1 of both. 14 studies were assessed as having between some and high risk of bias, while 10 were assessed as having low risk of bias. Benzodiazepines (WMD of 1.81 [CI 1.03, 2.58]) were significantly more effective than antidepressants (WMD of 0.83 [CI 0.64, 1.02]) for reducing somatic symptoms of GAD (Chi2 = 5.81, p = 0.02), and were also more effective (WMD of 2.46 [CI 1.83, 3.09]) in reducing psychic symptoms than antidepressants (WMD of 1.83 [CI 1.55, 2.10]), although this comparison did not reach statistical significance (Chi2 = 3.31, p = 0.07).

CONCLUSION

The finding that benzodiazepines were significantly more effective than antidepressants for somatic symptoms needs to be weighed up against potential benefits of antidepressants over benzodiazepines. It may be useful for future treatment guidelines for GAD to explicitly consider symptom subtype.

Differential Outcomes of Placebo Treatment Across 9 Psychiatric Disorders: A Systematic Review and Meta-Analysis

Importance

Placebo is the only substance systematically evaluated across common psychiatric diagnoses, but comprehensive cross-diagnostic comparisons are lacking.

Objective

To compare changes in placebo groups in recent high-quality randomized clinical trials (RCTs) across a broad spectrum of psychiatric disorders in adult patients.

Data Sources

MEDLINE and the Cochrane Database of Systematic Reviews were systematically searched in March 2022 for the latest systematic reviews meeting predetermined high-quality criteria for 9 major psychiatric diagnoses.

Study Selection

Using these reviews, the top 10 highest-quality (ie, lowest risk of bias, according to the Cochrane Risk of Bias tool) and most recent placebo-controlled RCTs per diagnosis (totaling 90 RCTs) were selected, adhering to predetermined inclusion and exclusion criteria.

Data Extraction and Synthesis

Following the Cochrane Handbook, 2 authors independently carried out the study search, selection, and data extraction. Cross-diagnosis comparisons were based on standardized pre-post effect sizes (mean change divided by its SD) for each placebo group. This study is reported following the Meta-analysis of Observational Studies in Epidemiology (MOOSE) reporting guideline.

Main Outcome and Measure

The primary outcome, pooled pre-post placebo effect sizes (dav) with 95% CIs per diagnosis, was determined using random-effects meta-analyses. A Q test assessed statistical significance of differences across diagnoses. Heterogeneity and small-study effects were evaluated as appropriate.

Results

A total of 90 RCTs with 9985 placebo-treated participants were included. Symptom severity improved with placebo in all diagnoses. Pooled pre-post placebo effect sizes differed across diagnoses (Q = 88.5; df = 8; P < .001), with major depressive disorder (dav = 1.40; 95% CI, 1.24-1.56) and generalized anxiety disorder (dav = 1.23; 95% CI, 1.06-1.41) exhibiting the largest dav. Panic disorder, attention-deficit/hyperactivity disorder, posttraumatic stress disorder, social phobia, and mania showed dav between 0.68 and 0.92, followed by OCD (dav = 0.65; 95% CI, 0.51-0.78) and schizophrenia (dav = 0.59; 95% CI, 0.41-0.76).

Conclusion and Relevance

This systematic review and meta-analysis found that symptom improvement with placebo treatment was substantial in all conditions but varied across the 9 included diagnoses. These findings may help in assessing the necessity and ethical justification of placebo controls, in evaluating treatment effects in uncontrolled studies, and in guiding patients in treatment decisions. These findings likely encompass the true placebo effect, natural disease course, and nonspecific effects.

Systematic review and network meta-analysis of agomelatine for the treatment of generalized anxiety disorder in adult patients

This systematic literature review aimed to assess the efficacy and tolerability of agomelatine versus approved medications for the treatment of generalized anxiety disorder (GAD) in adult patients. We selected randomized controlled trials on various medications used to treat GAD in adult patients. An existing systematic literature review (Kong et al., 2020) was used to identify relevant studies published before 2020. Outcomes of remission and discontinuation due to adverse events (AEs) were analyzed, following a random-effects network meta-analysis approach. Of 25 identified studies, 20 and 22 studies were included in the network meta-analysis for studying the remission and discontinuation (due to AEs) outcomes, respectively. A statistically significant difference in the remission rate was observed between agomelatine and pregabalin [odds ratio (OR), 2.22; 95% confidence interval (CI), 1.19-4.21]. For the other comparators, the results were nonsignificant; however, all the point estimates were in favor of agomelatine. Similarly, for discontinuation because of AEs, the point estimates leaned consistently toward agomelatine suggesting its higher tolerability. The probabilities of agomelatine having the highest remission rate and lowest discontinuation (due to AEs) rate were 67% and 68%, respectively. Based on its demonstrated effectiveness and tolerability, agomelatine can be considered as a drug of choice for the treatment of GAD.

Serum angioneurin levels following electroconvulsive therapy for mood disorders

OBJECTIVES

The efficacy of electroconvulsive therapy (ECT) in treating mood disorders (MDs) is hypothesized to be mediated by the induction of neurotrophic factors (denoted "angioneurins") that trigger neuronal plasticity. This study aimed to assess the effects of ECT on serum angioneurin levels in patients with MD.

METHODS

A total of 110 patients with MDs including 30 with unipolar depression, 25 with bipolar depression (BD), 55 with bipolar mania (BM), and 50 healthy controls were included in the study. Patients were subdivided into two groups: those who received ECT + medication (12 ECT sessions) and those who received only medication (no-ECT). Depressive and manic symptom assessments and measurements of vascular endothelial growth factor (VEGF), fibroblast growth factor-2, nerve growth factor (NGF), and insulin-like growth factor-1 levels in blood samples were performed at baseline and week 8.

RESULTS

Patients in the ECT group, specifically those with BD and BM, had significantly increased levels of VEGF compared to their baseline VEGF levels (p = 0.002). No significant changes in angioneurin levels were observed in the no-ECT group. Serum NGF levels were significantly associated with a reduction in depressive symptoms. Angioneurin levels were not associated with manic symptom reduction.

CONCLUSIONS

This study hints that ECT may increase VEGF levels with angiogenic mechanisms that amplify NGF signaling to promote neurogenesis. It may also contribute to changes in brain function and emotional regulation. However, further animal experiments and clinical validation are needed.

Inflammatory Cytokines Changed in Patients With Depression Before and After Repetitive Transcranial Magnetic Stimulation Treatment

Studies have found that repetitive transcranial magnetic stimulation rTMS can produce antidepressant effects by affecting inflammatory cytokines in patients with depression, which plays a key role in the therapeutic mechanism of antidepressants. This study aimed to explore the changes in inflammatory cytokine levels in patients with depression after 4 weeks of rTMS treatment to determine the possible antidepressant mechanism of rTMS. This prospective, double-blind, pseudo-stimulus-controlled study was conducted, and a total of 57 patients with depression and 30 healthy controls were recruited. Patients were randomly divided into the active rTMS (n = 29) and sham rTMS groups (n = 28). The Hamilton Depression Scale was used to evaluate depressive symptoms and their severity. The serum levels of seven inflammatory cytokines were measured using enzyme-linked immunosorbent assay. Inflammatory cytokines include high-sensitivity C-reactive protein (CRP-hc); tumor necrosis factor (TNF-α); interferon (IFN-γ); interleukin-2 (IL-2); interleukin-4 (IL-4); interleukin-6 (IL-6); and interleukin-8 (IL-8). At baseline, TNF-α (F = 36.699, p < 0.001), IFN-γ (F = 8.907, p < 0.001), IL-4 (F = 66.256, p < 0.001), and IL-2 (F = 9.162, p < 0.001) levels in the depression group were significantly different from those of healthy controls. In the self-control analysis of the active rTMS group, the levels of IL-2 and CRP-hc increased significantly after 2 and 12 weeks of treatment. In the sham-rTMS group, IFN-γ increased after 2 and 12 weeks of treatment. Our results revealed that the changes in inflammatory cytokines after rTMS treatment showed different patterns compared to the sham group, suggesting that the antidepressant effect of rTMS may be related to changes in inflammatory cytokines.

Comparative Remission Rates and Tolerability of Drugs for Generalised Anxiety Disorder: A Systematic Review and Network Meta-analysis of Double-Blind Randomized Controlled Trials

Background: Generalized anxiety disorder (GAD) is one of the most common psychiatric disorders associated with substantial dysfunction and socioeconomic burden. Pharmacotherapy is the first choice for GAD. Remission [Hamilton Anxiety Scale (HAM-A) score ≤7] is regarded as a crucial treatment goal for patients with GAD. There is no up-to-date evidence to compare remission rate and tolerability of all available drugs by using network meta-analysis. Therefore, the goal of our study is to update evidence and determine the best advantageous drugs for GAD in remission rate and tolerability profiles.

Method: We performed a systematic review and network meta-analysis of double-blind randomized controlled trials (RCTs). We searched PubMed, EMBASE, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, wanfang data, China Biology Medicine and ClinicalTrials.gov from their inception to March 2020 to identify eligible double-blind, RCTs reporting the outcome of remission in adult patients who received any pharmacological treatment for GAD. Two reviewers independently assessed quality of included studies utilizing the Cochrane Collaboration’s risk of bias tool as described in Cochrane Collaboration Handbook and extracted data from all manuscripts. Our outcomes were remission rate (proportion of participants with a final score of seven or less on HAM-A) and tolerability (treatments discontinuations due to adverse events). We calculated summary odds ratios (ORs) and 95% confidence intervals (CIs) of each outcome via pairwise and network meta-analysis with random effects.

Results: Overall, 30 studies were included, comprising 32 double-blind RCTs, involving 13,338 participants diagnosed as GAD by DSM-IV criteria. Twenty-eight trials were rated as moderate risk of bias, four trials as low. For remission rate, agomelatine (OR 2.70, 95% CI 1.74–4.19), duloxetine (OR 1.88, 95% CI 1.47–2.40), escitalopram (OR 2.03, 95% CI 1.48–2.78), paroxetine (OR 1.74, 95% CI 1.25–2.42), quetiapine (OR 1.88, 95% CI 1.39–2.55), and venlafaxine (OR 2.28, 95% CI 1.69–3.07) were superior to placebo. For tolerability, sertraline, agomelatine, vortioxetine, and pregabalin were found to be comparable to placebo. However, the others were worse than placebo in terms of tolerability, with ORs ranging between 1.86 (95% CI 1.25–2.75) for tiagabine and 5.98 (95% CI 2.41–14.87) for lorazepam. In head-to-head comparisons, agomelatine, duloxetine, escitalopram, quetiapine, and venlafaxine were more efficacious than tiagabine in terms of remission rate, ORs from 1.66 (95% CI 1.04–2.65) for duloxetine to 2.38 (95% CI 1.32–4.31) for agomelatine. We also found that agomelatine (OR 2.08, 95% CI 1.15–3.75) and venlafaxine (OR 1.76, 95% CI 1.08–2.86) were superior to vortioxetine. Lorazepam and quetiapine were poorly tolerated when compared with other drugs.

Conclusions: Of these interventions, only agomelatine manifested better remission with relatively good tolerability but these results were limited by small sample sizes. Duloxetine, escitalopram, venlafaxine, paroxetine, and quetiapine showed better remission but were poorly tolerated.

Comparative efficacy of add-on rTMS in treating the somatic and psychic anxiety symptoms of depression comorbid with anxiety in adolescents, adults, and elderly patients-A real-world clinical application

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is an effective adjuvant treatment for depression. Many patients with depression have comorbid anxiety symptoms. However, previous rTMS studies have focused on patients with depression, and often excluded comorbid anxiety. This real-world study aimed to investigate the comparative efficacy of add-on rTMS in treating the somatic and psychic anxiety symptoms of depression comorbid with anxiety in adolescents, adults and elderly patients.

METHODS

This study included 147 depression patients with anxiety symptoms who were treated with at least 10 sessions of rTMS. The symptoms of anxiety and depression were assessed with the Hamilton Rating Scale for Anxiety (HAMA) and the Hamilton Rating Scale for Depression (HAMD) at baseline and after 2 and 4 weeks of treatment. This was done to compare the improvement degree of add-on rTMS on somatic and psychic anxiety symptoms in adolescents, adults and elderly patients respectively.

RESULTS

Both somatic and psychic anxiety symptoms were significantly improved after the add-on rTMS in adolescents, adults and elderly patients. The improvement of somatic anxiety was better than that of psychic anxiety after rTMS treatment in elderly patients (t_2w=3.895, P<0.001; t_4w=2.823, P = 0.008).

LIMITATION

The overall sample was mostly composed of elderly patients, while adolescents and adult patients were fewer.

CONCLUSIONS

The add-on rTMS treatment can improve somatic anxiety better than psychic anxiety in depression with anxiety symptoms, especially in elderly patients.

Age-dependent association of polymorphisms in the promoter and 5'-untranslated region of the norepinephrine transporter gene with generalized anxiety disorder

BACKGROUND

Norepinephrine transporter (NET), which regulates synaptic norepinephrine for noradrenergic signaling, is involved in the pathogenesis of anxiety, while expression of the NET gene differs at different ages. Here, we examine whether genetic variants in the NET gene are associated, in an age-specific manner, with increased risk of generalized anxiety disorder (GAD), one of the most disabling anxiety disorders.

METHODS

Three common single-nucleotide polymorphisms (SNPs) in the promoter (rs168924: A/G; rs2242446: T/C) and 5'-untranslated region (5'-UTR) (rs2397771: G/C) of the NET gene were genotyped in 2,317 Han-Chinese participants (791 GAD patients and 1,526 controls; age: 20-65). Potential confounding factors, such as gender, stress levels and psychiatric comorbidities, were included as covariates.

RESULTS

An interaction between age and NET genotypes and haplotypes was found for the risk of GAD. In the younger participants, rs168924 minor allele G homozygotes had the lowest incidence of GAD; however, older subjects displayed an inverse pattern, with homozygous G/G carriers presenting the highest prevalence of GAD. Additionally, younger individuals carrying 2 copies of the GGT haplotype composed of rs2397771-rs168924-rs2242446 had the lowest rate of GAD. However, those with 2 copies of the same haplotype exhibited the highest risk of GAD in the older groups.

LIMITATIONS

Only 3 common SNPs in the promoter and 5'-UTR of the NET gene were analyzed.

CONCLUSIONS

Our findings are the first to demonstrate that potentially functional SNPs in the NET promoter and 5'-UTR are associated with an increased risk of GAD, and that such associations are determined in an age-specific way.

Meta-analysis of placebo group dropout in adult antidepressant trials

BACKGROUND

Minimizing dropouts across antidepressant, placebo-controlled trials remains a major opportunity to improve the efficiency of trials. This meta-analysis investigated placebo dropout rate and its predictors in second generation antidepressant (SGA) for anxiety, depression and obsessive-compulsive disorder (OCD).

METHODS

A random-effects meta-analysis was performed to examine placebo group dropout rate in SGA trials for depression, anxiety and OCD using Freeman - Tukey transformation. Stratified subgroup analysis by diagnostic indication was performed to examine the dropout rate across disorders. Meta-regression was performed to identify correlates between placebo dropout rate and trial and subject characteristics.

RESULTS

Meta-analysis included 148 trials with 18,016 participants receiving placebo. Across antidepressant trials the overall placebo dropout rate was 25% (dropout rate ± standard error (SE) = 0.25 ± 0.01, 95% CI: 0.23-0.27, z = 23.95, p < .001) and was similar across disorders (χ2 = 1.09, df = 2, p = .58). The placebo group dropout rate was 26% in depressive disorders, 25% in anxiety disorders and 22% in OCD. Across all diagnostic indications, earlier publication year, placebo lead-in, studies conducted in a single country (instead of internationally), longer trial duration, fewer study sites, more study visits and less baseline illness severity were associated with higher placebo dropout rate. Significant predictors of placebo dropout did not replicate across disorders.

CONCLUSION

No significant difference was found in placebo dropout rate between internalizing disorders with overall dropout rate for placebo groups in antidepressant trials being around 25%. Placebo dropouts in trials can be minimized by reducing subject burden in trials, enrolling more severely affected subjects and foregoing placebo lead-in periods.

A Systematic Review of Efficacy, Safety, and Tolerability of Duloxetine

Duloxetine is a serotonin-norepinephrine reuptake inhibitor approved for the treatment of patients affected by major depressive disorder (MDD), generalized anxiety disorder (GAD), neuropathic pain (NP), fibromyalgia (FMS), and stress incontinence urinary (SUI). These conditions share parallel pathophysiological pathways, and duloxetine treatment might be an effective and safe alternative. Thus, a systematic review was conducted following the 2009 Preferred Reporting Items (PRISMA) recommendations and Joanna Briggs Institute Critical (JBI) Appraisals guidelines. Eighty-five studies focused on efficacy, safety, and tolerability of duloxetine were included in our systematic review. Studies were subdivided by clinical condition and evaluated individually. Thus, 32 studies of MDD, 11 studies of GAD, 19 studies of NP, 9 studies of FMS, and 14 studies of SUI demonstrated that the measured outcomes indicate the suitability of duloxetine in the treatment of these clinical conditions. This systematic review confirms that the dual mechanism of duloxetine benefits the treatment of comorbid clinical conditions, and supports the efficacy, safety, and tolerability of duloxetine in short- and long-term treatments.

Pharmacological and psychological interventions for generalized anxiety disorder in adults: A network meta-analysis

Generalized anxiety disorder (GAD) is a significant and common mental illness with a lifetime prevalence of 3.7%. Regardless of the complexity of treatment decisions for GAD, few studies have conducted systematic comparisons of the efficacies of varying interventions. Thus, this study performed a valid network meta-analysis (NMA) of randomized controlled trials (RCTs) to synthesize direct and indirect evidence for alternative interventions for GAD. We searched four major bibliographic databases, the Cochrane Central Register of Controlled Trials, Embase, PsycINFO, and PubMed, for published RCTs of adult patients with a diagnosis of GAD and allowed for all comorbidities. A total of 91 articles (14,812 participants) were identified in the final NMA. The results showed that all pharmacological treatments except for serotonin modulators and second-generation antipsychotics had greater effects than placebo: norepinephrine-dopamine reuptake inhibitors (standardized mean difference (SMD) -1.84, 95% credible interval -3.05 to -0.62), noradrenergic and specific serotonergic antidepressants (-0.91, -1.62 to -0.20), melatonergic receptor agonists (-0.68, -1.15 to -0.21), selective serotonin reuptake inhibitors (SSRIs; -0.67, -0.90 to -0.43), azapirones (-0.58, -1.00 to -0.17), anticonvulsants (-0.56, -0.85 to -0.28), serotonin-norepinephrine reuptake inhibitors (SNRIs; -0.54, -0.79 to -0.30), and benzodiazepines (BZDs; -0.40, -0.65 to -0.15). Most psychological and self-help interventions exerted greater effects than the waitlist group. However, no psychological interventions had greater effects compared with the psychological placebo. Overall, most pharmacological interventions had larger effect sizes than psychological interventions, and most psychological interventions showed larger effect sizes than self-help interventions.

Emotion-based brain mechanisms and predictors for SSRI and CBT treatment of anxiety and depression: a randomized trial

Mechanisms and predictors for the successful treatment of anxiety and depression have been elusive, limiting the effectiveness of existing treatments and curtailing the development of new interventions. In this study, we evaluated the utility of three widely used neural probes of emotion (experience, regulation, and perception) in their ability to predict symptom improvement and correlate with symptom change following two first-line treatments-selective serotonin reuptake inhibitors (SSRIs) and cognitive-behavioral therapy (CBT). Fifty-five treatment-seeking adults with anxiety and/or depression were randomized to 12 weeks of SSRI or CBT treatment (ClinicalTrials.gov identifier: NCT01903447). Functional magnetic resonance imaging (fMRI) was used to examine frontolimbic brain function during emotion experience, regulation, and perception, as probed by the Emotion Regulation Task (ERT; emotion experience and regulation) and emotional face assessment task (EFAT; emotion perception). Brain function was then related to anxiety and depression symptom change. Results showed that both SSRI and CBT treatments similarly attenuated insula and amygdala activity during emotion perception, and greater treatment-related decrease in insula and amygdala activity was correlated with greater reduction in anxiety symptoms. Both treatments also reduced amygdala activity during emotion experience but brain change did not correlate with symptom change. Lastly, greater pre-treatment insula and amygdala activity during emotion perception predicted greater anxiety and depression symptom improvement. Thus, limbic activity during emotion perception is reduced by both SSRI and CBT treatments, and predicts anxiety and depression symptom improvement. Critically, neural reactivity during emotion perception may be a non-treatment-specific mechanism for symptom improvement.

Systematic review and meta-analysis: Dose-response curve of SSRIs and SNRIs in anxiety disorders

BACKGROUND

We aimed to examine the efficacy of selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) for anxiety disorders examining overall symptom improvement, likelihood of treatment response, time course of treatment response, individual pharmacological agent, diagnostic indication dose, and tolerability.

METHODS

We searched PubMed and Cochrane Central Register of Controlled Trials. We included randomized placebo-controlled clinical trials of SSRIs/SNRIs in adult patients with anxiety disorders that provided data at three or more time points. Extracted data included trial duration, weekly/biweekly anxiety scores for 12 weeks.

RESULTS

Meta-analysis included 57 trials (N = 16,056). A linear mixed model analysis based on weekly outcome data suggested that for SNRI a logarithmic model offered the best fit compared to placebo (indicating the greatest incremental improvement from baseline occurred early in treatment); whereas for SSRI a linear model provided the best fit (indicating a similar improvement over the duration of the acute treatment phase). There were no significant differences in efficacy between pharmacological agents within each class or when comparing SSRIs to SNRIs. The greatest treatment benefits were observed for social anxiety disorder for both medication classes. Higher doses of SSRIs, but not SNRIs, were associated with significantly greater symptom improvement and likelihood of treatment response. For both medical classes, higher doses were associated with an increased likelihood of dropout due to side effects.

CONCLUSIONS

SSRIs and SNRIs are effective in treating anxiety disorders. Higher doses of SSRIs within the therapeutic range are associated with greater treatment benefit, whereas higher doses of SNRIs are not.

Comparing the efficacy of benzodiazepines and serotonergic anti-depressants for adults with generalized anxiety disorder: a meta-analytic review

INTRODUCTION

Generalized anxiety disorder (GAD) is a common form of anxiety disorder. Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), and benzodiazepines (BZs) are the most commonly prescribed medications for GAD, but little is known about the relative efficacy of these pharmacological treatments. Areas covered: This study provides a meta-analytic review of the efficacy of these medications in the treatment of adults with GAD. A comprehensive literature search yielded 54 articles reporting 56 unique studies with 12,655 participants treated with either pill placebo (6,191 participants), SSRIs (16 trials, 2,712 participants), SNRIs (17 trials, 2,603 participants), or BZs (23 trials, 1,149 participants). The overall combined effect size was modest to moderate (Hedges' g = 0.37, p < 0.0001). Effect sizes decreased significantly over time. SSRIs (Hedges' g = 0.33) and SNRIs (Hedges' g = 0.36) demonstrated significantly lower effect sizes than BZs (Hedges' g = 0.50). These findings were not due to differences in treatment length or publication year. Expert opinion: The results of this study suggest that the most common forms of pharmacotherapy for adult GAD are moderately effective, with BZs being the most effective drug.

Efficacy and tolerability of short-term duloxetine treatment in adults with generalized anxiety disorder: A meta-analysis

OBJECTIVE

To investigate the efficacy and tolerability of duloxetine during short-term treatment in adults with generalized anxiety disorder (GAD).

METHODS

We conducted a comprehensive literature review of the PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and ClinicalTrials databases for randomized controlled trials(RCTs) comparing duloxetine or duloxetine plus other antipsychotics with placebo for the treatment of GAD in adults. Outcome measures were (1) efficacy, assessed by the Hospital Anxiety and Depression Scale(HADS) anxiety subscale score, the Hamilton Rating Scale for Anxiety(HAM-A) psychic and somatic anxiety factor scores, and response and remission rates based on total scores of HAM-A; (2) tolerability, assessed by discontinuation rate due to adverse events, the incidence of treatment emergent adverse events(TEAEs) and serious adverse events(SAEs). Review Manager 5.3 and Stata Version 12.0 software were used for all statistical analyses.

RESULTS

The meta-analysis included 8 RCTs. Mean changes in the HADS anxiety subscale score [mean difference(MD) = 2.32, 95% confidence interval(CI) 1.77-2.88, P<0.00001] and HAM-A psychic anxiety factor score were significantly greater in patients with GAD that received duloxetine compared to those that received placebo (MD = 2.15, 95%CI 1.61-2.68, P<0.00001). However, there was no difference in mean change in the HAM-A somatic anxiety factor score (MD = 1.13, 95%CI 0.67-1.58, P<0.00001). Discontinuation rate due to AEs in the duloxetine group was significantly higher than the placebo group [odds ratio(OR) = 2.62, 95%CI 1.35-5.06, P = 0.004]. The incidence of any TEAE was significantly increased in patients that received duloxetine (OR = 1.76, 95%CI 1.36-2.28, P<0.0001), but there was no significant difference in the incidence of SAEs (OR = 1.13, 95%CI 0.52-2.47, P = 0.75).

CONCLUSION

Duloxetine resulted in a greater improvement in symptoms of psychic anxiety and similar changes in symptoms of somatic anxiety compared to placebo during short-term treatment in adults with GAD and its tolerability was acceptable.

Predictors of Pharmacotherapy Response in Generalized Anxiety Disorder: A Systematic Review

BACKGROUND

Pharmacotherapy for generalized anxiety disorder (GAD) may be effective in reducing symptoms in the majority of patients. The study of moderators and predictors of treatment response may help clinicians both to select appropriate interventions to maximize the probability of response and to inform the general prognosis.

METHODS

A systematic literature search of electronic databases, selected authors, and reference lists was used to identify articles that reported trials of drug monotherapy in GAD. Data on predictors and moderators were extracted. Quality of evidence was determined by the presence of a priori hypotheses, number of variables investigated, adequate quality of the measurement, and use of interaction-effects testing.

RESULTS

From the 98 articles meeting inclusion criteria, 24 reported a total of 22 factors associated with treatment response. The reported results were heterogeneous, ranging over sociodemographic, clinical, comorbidity, genetic, and functional-imaging studies. Major depressive symptoms were found to moderate treatment outcome in favor of antidepressants versus benzodiazepines. Neuroticism, previous treatment, genetic polymorphisms (including serotonin receptor gene 2A), and functional activation of the anterior cingulate cortex and amygdala were identified as potential predictors of treatment response.

CONCLUSIONS

Correlates of poor emotion regulation predicted poor treatment response, but subclinical depression was the only variable capable of informing treatment selection in this review. Future research should focus on further exploring the value of depression as a moderator and on a narrower list of potential genetic, brain-imaging, and temperament predictors of response to pharmacotherapy in GAD.

Meta-analysis: Risk of hyperhidrosis with second-generation antidepressants

BACKGROUND

Our goal was to quantify the risk of hyperhidrosis associated with commonly used antidepressant agents and examine the impact of medication class, pharmacodynamics, and dose on risk of hyperhidrosis.

METHODS

We conducted a PubMed search to identify all double-blind, randomized, placebo-controlled trials examining the efficacy of second-generation antidepressant medications in the treatment of adults with a depressive disorder, anxiety disorders, or obsessive-compulsive disorder. We used a random-effects meta-analysis to examine the pooled risk ratio of hyperhidrosis reported as a side effect in adults treated with second-generation antidepressants compared to placebo. We used stratified subgroup analysis and metaregression to examine the effects of medication type, class, dosage, indication, and receptor affinity profile on the measured risk of hyperhidrosis.

RESULTS

We identified 76 trials involving 28,544 subjects. There was no significant difference in the risk of hyperhidrosis between serotonin-norepinephrine reuptake inhibitors (SNRI) [risk ratio (RR) = 3.17, 95% CI: 2.63-3.82] and selective serotonin reuptake inhibitors (SSRI) (RR = 2.93, 95% CI: 2.46-3.47) medications compared to placebo. All antidepressant medications were associated with a significantly increased risk of hyperhidrosis except fluvoxamine (RR = 0.56, 95% CI: 0.12-2.53), bupropion (RR = 1.23, 95% CI: 0.57-2.67), and vortioxetine (RR = 1.35, 95% CI: 0.79-2.33). The dose of SSRI/SNRI medications was not significantly associated with the risk of hyperhidrosis. Increased risk of hyperhidrosis was associated with increased affinity of SSRI/SNRI medications to the dopamine transporter.

CONCLUSION

Risk of hyperhidrosis was significantly increased with most antidepressant medications but was associated with dopamine transporter affinity.

Short-term efficacy and tolerability of venlafaxine extended release in adults with generalized anxiety disorder without depression: A meta-analysis

Background

Although efficacy of venlafaxine extended release (XR) for generalized anxiety disorder (GAD) has been reported in previous analyses in 2002 and 2004, the sample size was rather small and estimate of safety or tolerability was not clear. The present analysis had the advantage of large sample size and provided evidence for tolerability.

Methods

Literature databases were searched, including Pubmed, Embase, Cochrane Central Register of Controlled Trials, Web of science and clinical trials. 10 eligible articles were finally selected and data was extracted and logged into the Review Manager 5.3 by two independent authors. The risk of bias was evaluated by the Cochrane Collaboration’s Risk of Bias Tool and the stability of the results was assessed by sensitivity analysis. The publication bias was assessed by funnel plot and Egger’s/Begg’s test using Stata Version 12.0 software.

Results

In the current meta-analysis, 10 articles (14 studies) satisfying the inclusion criteria were analyzed. As efficacy outcomes, our findings indicated venlafaxine XR was significantly more effective than placebo according to mean change of the Hamilton Rating Scale for Anxiety total scores [mean difference = 3.31, 95% confidence interval(CI) 1.44–5.18, P = 0.0005], response [odds ratio(OR) = 1.83, 95%CI 1.58–2.12, P<0.00001], and remission (OR = 2.55, 95%CI 1.36–4.78, P = 0.003). In terms of tolerability, the most frequently reported treatment-emergent adverse events were nausea, dry mouth, dizziness, insomnia, somnolence, and headache. In addition, discontinuation due to all-cause (OR = 1.17, 95%CI 0.92–1.49, P = 0.19) was not significantly different between the two groups, whereas discontinuation due to adverse events was statistically higher in the venlafaxine XR group compared with the placebo treatment (OR = 2.80, 95%CI 2.21–3.54, P<0.00001) and discontinuation due to inefficacy was lower in venlafaxine than placebo treatment (OR = 0.26, 95%CI 0.17–0.40, P<0.00001). There was no significant publication bias and sensitivity analysis showed that our analysis exhibited high stability.

Conclusion

We concluded that venlafaxine XR (75–225 mg/day) is an effective and well-tolerated pharmacological treatment option for adult patients with GAD.

Obsessive-compulsive disorder has a reduced placebo (and antidepressant) response compared to other anxiety disorders: A meta-analysis

BACKGROUND

Previous studies have indicated that obsessive-compulsive disorder (OCD) might have a reduced placebo response compared to other anxiety-related disorders including generalized anxiety disorder, panic disorder, post-traumatic stress disorder, and social anxiety disorder. No previous analysis has directly compared antidepressant and placebo responses between OCD and these conditions.

METHOD

We analyzed pre-post change scores within drug and placebo groups as well as between-groups change scores (i.e., drug compared to placebo) for all FDA-approved antidepressants for the treatment of these five anxiety-related disorders. Antidepressants included duloxetine, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, and venlafaxine. Random effects meta-analysis was used to examine all trials submitted to the FDA, plus additional post-approval trials available from manufacturer-sponsored clinical trial registers. Clinician-rated symptom inventories were the outcome measures for all conditions to facilitate comparisons across diagnoses.

RESULTS

Fifty-six trials met inclusion criteria. OCD had significantly lower pre-post effect sizes (ps<0.003) for both placebo (Hedges' g=0.49) and antidepressants (g=0.84) compared to the other four conditions (gs between 0.70 and 1.10 for placebo and 1.11 and 1.40 for antidepressants). However, the drug-placebo effect sizes did not significantly differ across diagnoses (Q(4)=6.09, p=0.193, I² =34.3% [95% CI: -7.0,59.7]), with gs between=0.26 and 0.39.

CONCLUSIONS

Overall pre-post change scores were smaller for OCD compared to other anxiety disorders for both antidepressants and placebo, although drug-placebo effects sizes did not significantly differ across disorders. Theoretical and clinical implications for the understanding and treatment of OCD are discussed.

Duloxetine in treating generalized anxiety disorder in adults: A meta-analysis of published randomized, double-blind, placebo-controlled trials

INTRODUCTION

We carried out a meta-analysis of published randomized, double-blind, placebo-controlled trails to assess the efficacy and tolerability of duloxetine in treating generalized anxiety disorder (GAD).

METHODS

A literature search was conducted using PubMed, ISI Web of Science, Medline, Cochrane Central Register of Controlled Trials databases until October 2014. The search terms used were "anxiety or anxious or generalized anxiety disorder" and "duloxetine or Cymbalta." Meta-analysis was conducted using Revman 5.1. A fixed-effects model was carried out on the response rates, remission rates, and symptom improvement. Risk ratio (RR) and mean difference (MD) were calculated. The overall effect size was calculated with 95% confidence intervals (CIs).

RESULTS

Seven studies (n = 2,674) were found eligible for inclusion in analysis. Six studies provided data on response, which showed a significant difference between duloxetine and placebo (n = 1,975, RR = 1.48, 95% CI, 1.34-1.63). Remission rates revealed significant superiority of duloxetine (n = 2,399, RR = 1.60, 95% CI, 1.43-1.80). Change from baseline scores on Hamilton Rating Scale for Anxiety showed a reduction in anxiety symptoms to be significantly efficient for duloxetine (n = 1,135, MD = 3.34, 95% CI, 2.37-4.32). Duloxetine increased statistically Sheehan Disability Scale total score (n = 1,652, MD = 2.84, 95% CI, 2.08-3.60). The discontinuation of the duloxetine was not significantly different from that of the placebo.

CONCLUSION

Duloxetine is moderately effective in treating GAD with improvement in overall function and well tolerability.

The noradrenergic paradox: implications in the management of depression and anxiety

Both major depressive disorder and the anxiety disorders are major causes of disability and markedly contribute to a significant global burden of the disease worldwide. In part because of the significant socioeconomic burden associated with these disorders, theories have been developed to specifically build clinical treatment approaches. One such theory, the monoaminergic hypothesis, has led to the development of several generations of selective and nonselective inhibitors of transporters of serotonin and norepinephrine, with the goal of augmenting monoaminergic transmission. These efforts have led to considerable success in the development of antidepressant therapeutics. However, there is a strong correlation between enhanced noradrenergic activity and fear and anxiety. Consequently, some physicians have expressed concerns that the same enhanced noradrenergic activity that alleviates depression could also promote anxiety. The fact that the serotonergic and noradrenergic reuptake inhibitors are successfully used in the treatment of anxiety and panic disorders seems paradoxical. This review was undertaken to determine if any clinical evidence exists to show that serotonergic and noradrenergic reuptake inhibitors can cause anxiety. The PubMed, EMBASE, and Cochrane Library databases were searched, and the results limited to randomized, double-blind, placebo-controlled studies performed in nongeriatric adults and with clear outcome measures were reported. Based on these criteria, a total of 52 studies were examined. Patients in these studies suffered from depression or anxiety disorders (generalized and social anxiety disorders, panic disorder, and posttraumatic stress disorder). The large majority of these studies employed venlafaxine or duloxetine, and the remainder used tri-cyclic antidepressants, atomoxetine, or reboxetine. All the studies reported clinically significant alleviation of depressive and/or anxious symptoms by these therapeutics. In none of these studies was anxiety a treatment-emergent adverse effect. This review argues against the impression that enhanced generalized noradrenergic activity promotes the emergence of anxiety.

Pharmacological treatment for generalized anxiety disorder in adults: an update

INTRODUCTION

Modest response and remission rates for the selective serotonin reuptake inhibitors and the serotonin-norepinephrine reuptake inhibitors, coupled with mounting evidence that the tolerability of the antidepressants (ADs) may have been overstated in the literature, has contributed to changes in prescribing patterns for generalized anxiety disorder (GAD). New interest in the absence of evidence that supports these standard therapies as superior to benzodiazepines stimulated a review of the literature.

AREAS COVERED

A literature search was conducted in the MedLine database with search terms 'generalized anxiety disorder' and 'treatment' for purposes of including relevant literature related to pharmacologic treatment of GAD. Aside from a review of pivotal literature, the authors also included newer studies that evaluated novel drug treatments. Last, the database was searched for benzodiazepine comparisons to standard therapy secondary to concerns that such literature is sparse. The review of newer modalities and the decision to include related literature was also based on the strength of the evidence and the status of their approval for the treatment of GAD.

EXPERT OPINION

Although ADs remain the most frequently prescribed medications for GAD, alternative and off-label therapies such as pregabalin, the atypical antipsychotics and vortioxetine are garnering interest. Based on the evidence available to us, it is our recommendation that along with the ADs, benzodiazepines be considered a possible first-line therapy in eligible patients based on the discretion and clinical judgment of the treating physician.

Efficacy and safety of duloxetine in the treatment of older adult patients with generalized anxiety disorder: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

This was a flexible-dosed study to evaluate the efficacy and safety of duloxetine 30-120 mg once daily in the treatment of generalized anxiety disorder (GAD) in older adult patients.

METHODS

Patients with GAD, who were at least 65 years of age, were randomly assigned to double-blind treatment with either duloxetine (N = 151) or placebo (N = 140). The primary efficacy measure was the Hamilton Anxiety Rating Scale (HAM-A) total score, and the primary endpoint was at week 10. Global functioning was assessed by the Sheehan Disability Scale (SDS). Safety and tolerability was assessed by the occurrence of treatment-emergent adverse events, serious adverse events, laboratory analyses, and vital signs. Analyses were conducted on an intent-to-treat basis.

RESULTS

The overall baseline mean HAM-A total score was 24, and SDS global score was 14. Completion rates were 75% for placebo and 76% for duloxetine. At week 10, duloxetine was superior to placebo on mean changes from baseline in HAM-A total scores (-15.9 vs. -11.7, p < 0.001) and in SDS global scores (-8.6 vs. -5.4, p < 0.001). Treatment-emergent adverse events occurred in ≥5% of duloxetine-treated patients and twice the rate than with placebo including constipation (9% vs. 4%, p = 0.06), dry mouth (7% vs. 1%, p = 0.02), and somnolence (6% vs. 2%, p = 0.14).

CONCLUSION

Duloxetine treatment was efficacious in the improvement of anxiety and functioning in older adult patients with GAD, and the safety profile was consistent with previous GAD studies.

The risk of bleeding with duloxetine treatment in patients who use nonsteroidal anti-inflammatory drugs (NSAIDs): analysis of placebo-controlled trials and post-marketing adverse event reports

Purpose

To assess the safety of duloxetine with regards to bleeding-related events in patients who concomitantly did, versus did not, use nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin.

Methods

Safety data from all placebo-controlled trials of duloxetine conducted between December 1993 and December 2010, and post-marketing reports from duloxetine-treated patients in the US Food and Drug Administration Adverse Event Reporting System (FAERS), were searched for bleeding-related treatment-emergent adverse events (TEAEs). The percentage of patients with bleeding-related TEAEs was summarized and compared between treatment groups in all the placebo-controlled studies. Differences between NSAID user and non-user subgroups from clinical trial data were analyzed by a logistic regression model that included therapy, NSAID use, and therapy-by-NSAID subgroup interaction. In addition, to determine if higher duloxetine doses are associated with an increased incidence of bleeding-related TEAEs, and whether the use of concomitant NSAIDs might influence the dose effect if one exists, placebo-controlled clinical trials with duloxetine fixed doses of 60 mg, 120 mg, and placebo were analyzed. Also, the incidence of bleeding-related TEAEs reported for duloxetine alone was compared with the incidence in patients treated with duloxetine and concomitant NSAIDs. Finally, the number of bleeding-related cases reported for duloxetine in the FAERS database was compared with the numbers reported for all other drugs.

Results

Across duloxetine clinical trials, there was a significantly greater incidence of bleeding-related TEAEs in duloxetine- versus placebo-treated patients overall and also in those patients who did not take concomitant NSAIDS, but no significant difference was seen among those patients who did take concomitant NSAIDS. There was no significant difference in the incidence of bleeding-related TEAEs in the subset of patients treated with duloxetine 120 mg once daily versus those treated with 60 mg once daily regardless of concomitant NSAID use. The combination of duloxetine and NSAIDs was associated with a statistically significantly higher incidence of bleeding-related TEAEs compared with duloxetine alone. A similarly higher incidence of bleeding-related TEAEs was seen in patients treated with placebo and concomitant NSAIDs compared with placebo alone. Bleeding-related TEAEs reported in the FAERS database were disproportionally more frequent for duloxetine taken with NSAIDs compared with the full FAERS background, but there was no difference in the reporting of bleeding-related TEAEs when the cases reported for duloxetine taken with NSAIDs were compared against the cases reported for NSAIDs alone.

Conclusion

Concomitant use of NSAIDs was associated with a higher incidence of bleeding-related TEAEs in clinical trials regardless of whether patients were taking duloxetine or placebo; bleeding-related TEAEs did not appear to increase along with duloxetine dose regardless of NSAID use. In spontaneously reported post-marketing data, the combination of duloxetine and NSAID use was not associated with an increased reporting of bleeding-related events when compared to NSAID use alone.

The best next drug in the course of generalized anxiety disorders: the "PN-GAD-algorithm"

OBJECTIVE

Today, there are many pharmacotherapeutic options for generalized anxiety disorder (GAD). The question is, which is the best medication for a particular patient at a particular moment? This is especially challenging because GAD is by definition a chronic disorder and new interventions should learn from earlier experiences. An algorithm which can help to use pretreatment information for drug selection is the "Pretreatment - Next Treatment (PN) - Algorithm". This article introduces an PN-algorithm for GAD.

METHODS AND RESULTS

For the development of a GAD-specific PN-algorithm, all possible pharmacological options for GAD are reviewed and brought into a rank order on the basis of scientific evidence regarding efficacy, tolerability, or price: (1) pregabalin, (2) venlafaxine XR, (3) selective serotonin reuptake inhibitors, (4) tricyclic antidepressants, (5) buspirone, (6) antipsychotics, (7) benzodiazepines, and (8) hydroxyzine. Based on this hierarchy and patient-specific information, a decision algorithm is derived, which allows to assess and evaluate pretreatment and to select the drug with no contraindications, limited negative or convincing positive effects, or the option which has not been used so far but which is the next compound in the hierarchy.

CONCLUSIONS

The "PN-GAD-algorithm" can be easily translated into a checklist to support clinical decision-making. It can also help to increase patient empowerment and cooperation in long-term treatment.

Comprehensive review of generalized anxiety disorder in primary care in Europe

OBJECTIVE

This review aims to summarize meta-analyses and other relevant data relating to the efficacy and safety of the various treatment options for generalized anxiety disorder (GAD) in Europe. In addition, it will provide an overview of the prevalence, burden, and recognition of the disorder, with a view to raise awareness of GAD and inform primary care practitioners.

RESEARCH DESIGN AND METHODS

Relevant research or review articles on psychological or pharmacological treatments for GAD published in the English language between March 2006 and March 2012 were identified via a literature search in PubMed and ISI Web of Knowledge and from the Cochrane Library. Other relevant references/clinical guidelines were individually selected by the authors.

RESULTS

Prevalence rates of GAD vary across Europe but its economic and social burden is increasing. A large proportion of patients with GAD present with symptoms in primary care. However, due to the disorder's complexity and the incidence of comorbid diseases, some primary care physicians may lack the knowledge or confidence to effectively recognize, manage, and/or treat the disorder. This is despite psychological and pharmacological treatments being available for the effective management of GAD.

CONCLUSIONS

GAD remains a difficult disorder to detect and comorbid complications add to its economic and social burden. Early detection and intervention reduces the societal burden and improves GAD patients' quality of life and functional ability. Primary care practitioners play a key role in identifying and treating patients with GAD.

The cost effectiveness of pharmacological treatments for generalized anxiety disorder

BACKGROUND

Generalized anxiety disorder (GAD) is one of the most prevalent anxiety disorders, with important implications for patients and healthcare resources. However, few economic evaluations of pharmacological treatments for GAD have been published to date, and those available have assessed only a limited number of drugs.

OBJECTIVE

To assess the cost effectiveness of pharmacological interventions for patients with GAD in the UK.

METHODS

A decision-analytic model in the form of a decision tree was constructed to compare the costs and QALYs of six drugs used as first-line pharmacological treatments in people with GAD (duloxetine, escitalopram, paroxetine, pregabalin, sertraline and venlafaxine extended release [XL]) and 'no pharmacological treatment'. The analysis adopted the perspective of the NHS and Personal Social Services (PSS) in the UK. Efficacy data were derived from a systematic literature review of double-blind, randomized controlled trials and were synthesized using network meta-analytic techniques. Two network meta-analyses were undertaken to assess the comparative efficacy (expressed by response rates) and tolerability (expressed by rates of discontinuation due to intolerable side effects) of the six drugs and no treatment in the study population. Cost data were derived from published literature and national sources, supplemented by expert opinion. The price year was 2011. Probabilistic sensitivity analysis was conducted to evaluate the underlying uncertainty of the model input parameters.

RESULTS

Sertraline was the best drug in limiting discontinuation due to side effects and the second best drug in achieving response in patients not discontinuing treatment due to side effects. It also resulted in the lowest costs and highest number of QALYs among all treatment options assessed. Its probability of being the most cost-effective drug reached 75 % at a willingness-to-pay threshold of £20,000 per extra QALY gained.

CONCLUSION

Sertraline appears to be the most cost-effective drug in the treatment of patients with GAD. However, this finding is based on limited evidence for sertraline (two published trials). Sertraline is not licensed for the treatment of GAD in the UK, but is commonly used by primary care practitioners for the treatment of depression and mixed depression and anxiety.

The diagnosis and treatment of generalized anxiety disorder

BACKGROUND

Generalized anxiety disorder (GAD) is a common and serious disease with a lifetime prevalence of 4.3% to 5.9%. It is underdiagnosed in primary care.

METHODS

Recommendations on the treatment of GAD are given on the basis of all available findings from pertinent randomized trials, retrieved by a selective search of the literature.

RESULTS

Among psychotherapeutic techniques, various kinds of cognitive behavioral therapy (CBT) have been found useful in controlled trials. The drugs of first choice include selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephine reuptake inhibitors (SNRIs), and the calcium-channel modulator pregabalin. Tricyclic antidepressants are also effective but have more adverse effects than SSRIs. Although benzodiazepines are effective anxiolytic agents for short-term use, they should not be given over the long term because of the danger of addiction. Buspirone, an azapirone, was found to be effective in a small number of trials, but the findings across trials are inconsistent. The response rate of GAD to CBT in published studies lies between 47% and 75%, while its response rate to drug treatment lies between 44% and 81%.

CONCLUSION

The treatment of GAD with CBT and drugs is evidence-based and has a good chance of improving the manifestations of the disorder.

Generalizability of clinical trial results for generalized anxiety disorder to community samples

BACKGROUND

There has been little research on the generalizability of clinical trials for generalized anxiety disorder (GAD). The present study examines the generalizability of pharmacological and psychotherapy clinical trials' results of individuals with DSM-IV GAD to a large community sample.

METHODS

Data were drawn from the National Epidemiological Survey on Alcohol and Related Conditions (NESARC), a large national representative face-to-face sample of 43,093 adults of the United States population. We applied a standard set of eligibility criteria representative of GAD pharmacological and psychotherapy clinical trials to all adults with past 12 months GAD (n = 894), and to a subgroup of participants seeking treatment (n = 329). Our aim was to assess how many participants with GAD would fulfil typical eligibility criteria.

RESULTS

We found that more than seven out of 10 participants with GAD were excluded by at least one criterion. In the subgroup of GAD participants who sought treatment, the exclusion rate by at least one criterion raised to more than eight out of 10 participants with GAD. For the overall sample and the treatment-seeking subsample, having a current depression was the criterion excluding the highest percentage of individuals. Having a lifetime history of bipolar disorder, a current significant medical condition, a current diagnosis of alcohol abuse or dependence, and a social or specific phobia also excluded a substantial proportion of individuals in both samples.

CONCLUSIONS

Clinical trials exclude a majority of adults with GAD. Clinical trials should carefully consider the impact of eligibility criteria on the generalizability of their results.

Pharmacotherapy of anxiety disorders: a critical review

Given the enormous contribution of anxiety disorders to the burden of disease, it is key to optimize their prevention and treatment. In this critical review we assess advances in the pharmacotherapy of anxiety disorders, as well as remaining challenges, in recent decades, the field has seen rigorous clinical trial methods to quantify the efficacy and safety of serendipitously discovered agents, more focused development of medications with selective mechanisms of action, and the gradual translation of insights from laboratory research into proof-of-principle clinical trials. On the positive side, a considerable database of studies shows efficacy and relative tolerability of the selective serotonin reuptake inhibitors in the major anxiety disorders, and secondary analyses of such datasets have informed questions such as optimal definition of response and remission, optimal dose and duration, and comparative efficacy of different agents. Significant challenges in the field include barriers to appropriate diagnosis and treatment of anxiety disorders, failure of a significant proportion of patients to respond to first-line pharmacotherapy agents, and a limited database of efficacy or effectiveness studies to guide treatment in such cases.

Pharmacological treatment of generalized anxiety disorder

INTRODUCTION

Generalized anxiety disorder (GAD) is a chronic, relapsing, debilitating disorder, associated with markedly impaired social and occupational functioning. Pharmacological treatment is considered standard care and several drug classes are now FDA approved for the treatment of GAD. While there are clear data for the efficacy of short-term acute treatment, long-term treatment and treatment-resistant GAD remain challenging.

AREAS COVERED

This article describes current pharmacological treatment options for GAD, with focus on benzodiazepines, azapirones, antidepressants and anticonvulsant and antipsychotic drugs. Recent findings from placebo-controlled clinical trials are reviewed and evidence-based clinical implications are discussed. A PubMed search was completed using the terms: 'generalized anxiety disorder AND treatment' and 'generalized anxiety disorder AND therapy'. Additional pivotal trials were included for a historical perspective (older landmark trials that established efficacy and safety for older drug classes in the treatment of GAD).

EXPERT OPINION

Efficacy for treatment of GAD has been established for several different drug classes. At present, based on clear efficacy and good tolerability, first-line treatment with either a selective serotonin reuptake inhibitor (SSRI) or a serotonin-norepinephrine reuptake inhibitor (SNRI) is indicated. If an initial, at least moderate, clinical response is achieved under antidepressant therapy, treatment should be at least continued for 12 months.

Duloxetine treatment and glycemic controls in patients with diagnoses other than diabetic peripheral neuropathic pain: a meta-analysis

OBJECTIVE

Mood disorders are often associated with poor glycemic control, and antidepressant treatments for mood and pain disorders can alter plasma glucose levels in patients with diabetes. A previous meta-analysis from three studies showed that duloxetine modestly increased fasting plasma glucose (FPG) and HbA(1c) levels in patients with diabetic peripheral neuropathic pain (DPNP). This meta-analysis examined whether there were any short- and long-term effects of duloxetine (20-120 mg/day) on glycemic control in patients with diagnoses other than DPNP.

RESEARCH DESIGN AND METHODS

Short-term data (9-27 weeks): seven studies of duloxetine in general anxiety disorder, fibromyalgia, and chronic lower back pain (CLBP). Long-term data: 41-week, uncontrolled extension of the short-term CLBP study and 52-week study in patients with recurrence of major depressive disorder.

MAIN OUTCOME MEASURES

Baseline-to-endpoint changes in FPG and HbA(1c) levels.

RESULTS

In short-term studies, patients were randomly assigned to placebo (n = 1098) or duloxetine (n = 1563). Mean baseline-to-endpoint changes in FPG and HbA(1c) did not significantly differ in duloxetine-treated patients compared with placebo-treated patients. In the 41-week study (n = 181), duloxetine-treated patients experienced a small but significant within-group baseline-to-endpoint increase in HbA(1c) (mean change = 0.1%; p < 0.001). This result was in contrast to absence of effect on mean baseline-to-endpoint within-group changes in FPG (p = 0.326) in that study, and to absence of between-treatment changes in FPG (p = 0.744) and HbA(1c) (p = 0.180) in the 52-week placebo-controlled study.

CONCLUSION

Duloxetine treatment did not significantly alter FPG and HbA(1c) levels compared with placebo treatment in the short-term studies. A small but statistically significant within-group increase in HbA(1c) was found in the 41-week study, but not in between-treatment group differences in the 52-week study. Neither of the long-term studies showed significant changes in the FPG levels. The small, non-reproducible HbA(1c) increase in one study of patients without DPNP may have resulted from patients with unrecognized diabetes in these trials.

Use of duloxetine in patients with an anxiety disorder, or with comorbid anxiety and major depressive disorder: a review of the literature

IMPORTANCE OF THE FIELD

Except for generalized anxiety disorder, few reports have been published on the efficacy, safety and tolerability of duloxetine in patients with anxiety disorders individually or in comorbidity with major depressive disorder (MDD).

AREAS COVERED IN THIS REVIEW

The literature search in Medline (dating back to 1966) and Embase (dating back to 1988) databases was conducted using the OVID interface on 9 April 2009, restricted to any article or abstract in English, per title, reporting any information on the use of duloxetine in patients with any anxiety disorder with or without concomitant MDD. A systematic review approach was taken.

WHAT THE READER WILL GAIN

The reader will gain knowledge of the current data available on the use of duloxetine to treat patients with anxiety disorders individually or in comorbidity with MDD.

TAKE HOME MESSAGE

Duloxetine could be considered an effective treatment option in the treatment of anxiety disorders individually or in comorbidity with each other, or with MDD; however, apart from the well-demonstrated efficacy, tolerability and safety of duloxetine in the treatment of MDD with or without anxiety and GAD, data on this subject are preliminary and very limited, and more research is warranted.

Profile of adverse events with duloxetine treatment: a pooled analysis of placebo-controlled studies

BACKGROUND

The serotonin and noradrenaline (norepinephrine) reuptake inhibitor duloxetine has been approved in the US and elsewhere for a number of indications, including psychiatric illnesses and chronic pain conditions. Because the patient populations are diverse within these approved indications, and duloxetine is not yet approved for treatment of other conditions, we wanted to determine if adverse event profiles would differ among patients being treated for these various conditions.

OBJECTIVE

To provide detailed information on the adverse events associated with duloxetine and to identify differences in the adverse event profile between treatment indications and patient demographic subgroups.

METHODS

Data were analysed from all placebo-controlled trials of duloxetine completed as of December 2008. The 52 studies included 17,822 patients (duloxetine n = 10,326; placebo n = 7496) with major depressive disorder, generalized anxiety disorder, diabetic peripheral neuropathic pain, fibromyalgia, osteoarthritis knee pain (OAKP), chronic lower back pain and lower urinary tract disorders. The main outcome measures were rates of treatment-emergent adverse events (TEAEs) and adverse events reported as the reason for discontinuation.

RESULTS

The overall TEAE rate was 57.2% for placebo-treated patients and 72.4% for duloxetine-treated patients (p < or = 0.001). Patients with OAKP had the lowest TEAE rate (placebo 36.7% vs duloxetine 50.2%, p < or = 0.01), while patients with fibromyalgia had the highest rate (placebo 80.0% vs duloxetine 89.0%, p < or = 0.001). The most common TEAE for all indications was nausea (placebo 7.2% vs duloxetine 23.4%, p < or = 0.001), which was predominantly mild to moderate in severity. No statistically significant treatment-by-subgroup interactions for age were found between placebo and duloxetine treatment for the most common TEAEs. The rates of duloxetine-associated dry mouth and fatigue were greater in women than in men (13.1% vs 10.4%, interaction p = 0.004; and 9.4% vs 7.6%, interaction p = 0.03, respectively). Duloxetine-associated dry mouth incidence was higher in Caucasians than non-Caucasians (13.2%, 11.0%, interaction p = 0.04).

CONCLUSIONS

Duloxetine treatment is associated with significantly higher rates of common TEAEs versus placebo, regardless of indication or demographic subgroup. Differences across indications are likely to be attributable to the underlying condition rather than duloxetine, as suggested by the similar trends observed in placebo- and duloxetine-treated patients.

Duloxetine: a review of its use in the treatment of generalized anxiety disorder

Duloxetine (Cymbalta(R)) is a potent serotonin and noradrenaline (norepinephrine) reuptake inhibitor (SNRI) in the CNS. It is indicated for the treatment of generalized anxiety disorder (GAD) as well as other indications. In patients with GAD of at least moderate severity, oral duloxetine 60-120 mg once daily was effective with regard to improvement from baseline in assessments of anxiety and functional impairment, and numerous other clinical endpoints. Longer-term duloxetine 60-120 mg once daily also demonstrated efficacy in preventing or delaying relapse in responders among patients with GAD. In addition, duloxetine was generally well tolerated, with most adverse events being of mild to moderate severity in patients with GAD in short- and longer-term trials. Additional comparative and pharmacoeconomic studies are required to position duloxetine among other selective serotonin reuptake inhibitors and SNRIs. However, available clinical data, and current treatment guidelines, indicate that duloxetine is an effective first-line treatment option for the management of GAD. Duloxetine is a potent and selective inhibitor of serotonin and noradrenaline transporters, and a weak inhibitor of dopamine transporters. It has a low affinity for neuronal receptors, such as alpha(1)- and alpha(2)-adrenergic, dopamine D(2), histamine H(1), muscarinic, opioid and serotonin receptors, as well as ion channel binding sites and other neurotransmitter transporters, such as choline and GABA transporters. It does not inhibit monoamine oxidase types A or B. The pharmacokinetics of duloxetine in healthy volunteers were dose proportional over the range of 40-120 mg once daily. Steady state was typically reached by day 3 of administration. Duloxetine may be administered without regard to food or time of day. Duloxetine is highly protein bound and is widely distributed throughout tissues. It is rapidly and extensively metabolized in the liver by cytochrome P450 (CYP) 1A2 and 2D6, and its numerous metabolites, which are inactive, are mainly excreted in the urine. The mean elimination half-life of duloxetine is approximately 12 hours. Duloxetine is a substrate for CYP1A2 and CYP2D6 and a moderate inhibitor of CYP2D6. Concomitant use of duloxetine and potent CYP1A2 inhibitors should be avoided and duloxetine should be used with caution in patients receiving drugs that are extensively metabolized by CYP2D6, particularly those with a narrow therapeutic index. Duloxetine was effective in the short-term treatment of patients with primary GAD of at least moderate severity. In four randomized, double-blind, placebo-controlled, multicentre, phase III trials, duloxetine 60-120 mg once daily for 9 or 10 weeks was significantly more effective than placebo with regard to the primary endpoint of mean change in Hamilton Anxiety Rating Scale (HAM-A) total score from baseline to study endpoint. In addition, all other endpoints were generally improved from baseline to a greater extent with duloxetine 60-120 mg once daily than with placebo. Duloxetine also improved patient role functioning (assessed using Sheehan Disability Scale global impairment functioning scores), health-related quality of life and patient well-being compared with placebo. Duloxetine was effective in patients with GAD who were aged >/=65 years. Pooled results of data from the two short-term efficacy trials that also included an active comparator arm showed that the mean change in HAM-A scores with duloxetine relative to placebo were of the same magnitude as those with venlafaxine extended release versus placebo. Duloxetine 60-120 mg once daily was also more effective than placebo in preventing or delaying relapse in responders to duloxetine in a longer-term study. In this study, patients with GAD received duloxetine during a 26-week, open-label, acute treatment phase and responders were then randomized to continue on duloxetine or receive placebo during a 26-week, double-blind, continuation phase. Time to relapse was significantly longer in duloxetine recipients than in placebo recipients. In addition, significantly fewer duloxetine recipients than placebo recipients relapsed during the double-blind phase of the trial and more duloxetine recipients achieved remission. Short- (9-10 weeks) and longer-term (52 weeks) treatment with duloxetine 60-120 mg once daily was generally well tolerated in patients with GAD, with the majority of adverse events being of mild to moderate severity. Nausea, dry mouth, headache, constipation, dizziness and fatigue were among the most common treatment-emergent adverse events. The adverse event profile of duloxetine did not differ with dose or treatment duration. Significantly more patients receiving short-term duloxetine than placebo discontinued treatment because of an adverse event, with nausea being the only event that resulted in significantly more treatment discontinuations in duloxetine recipients than in placebo recipients. Serious adverse events were uncommon with both short- and longer-term duloxetine treatment. Two episodes of attempted suicide and one episode of completed suicide occurred in duloxetine recipients during the 24-week open-label phase of a longer-term trial. No deaths or suicides were reported in any of the short-term trials. Discontinuation-emergent adverse events, most commonly nausea and dizziness, occurred in up to one-third of duloxetine recipients in the short-term trials.

Duloxetine in the treatment of generalized anxiety disorder

Duloxetine, a medication with effects on both serotonin and noradrenaline transporter molecules, has recently been approved for the treatment of generalized anxiety disorder. The evidence for its efficacy lies in a limited number of double blind, placebo controlled comparisons. Statistically significant improvements in the Hamilton Anxiety Rating Scale from baseline were demonstrated in all studies at doses of 60 to 120 mg per day. The significance of such changes in terms of clinical improvements compared to placebo is less certain, particularly when the effect size of the change is calculated. In comparative trials with venlafaxine, duloxetine was as effective in providing relief of anxiety symptoms. In addition to improvements in clinical symptoms duloxetine has also been associated with restitution of role function as measured by disability scales. Duloxetine use is associated with nausea, dizziness, dry mouth, constipation, insomnia, somnolence, hyperhidrosis, decreased libido and vomiting. These treatment emergent side effects were generally of mild to moderate severity and were tolerated over time. Using a tapered withdrawal schedule over two weeks in the clinical trials, duloxetine was associated with only a mild withdrawal syndrome in up to about 30% of patients compared to about 17% in placebo treated patients. Duloxetine in doses of up to 200 mg twice daily did not prolong the QTc interval in healthy volunteers. Like other agents with dual neurotransmitter actions duloxetine reduces the symptoms of generalized anxiety disorder in short term treatments. Further evidence for its efficacy and safety in long term treatment is required.

Efficacy and tolerability of duloxetine in elderly patients with generalized anxiety disorder: a pooled analysis of four randomized, double-blind, placebo-controlled studies

OBJECTIVE

To assess the efficacy and tolerability of duloxetine in elderly patients with generalized anxiety disorder (GAD).

METHODS

Acute-phase data from a subset of patients (>or=65 years) with GAD were pooled from four randomized, double-blind, placebo-controlled trials of duloxetine (3 flexible, 1 fixed dosing). Patients were treated with duloxetine 60-120 mg once daily or placebo for 9-10 weeks. The primary outcome measure was the mean baseline-to-endpoint change in Hamilton anxiety scale (HAMA) total score. Secondary measures included the HAMA psychic and somatic anxiety subscales and the Hospital Anxiety Depression Scale (HADS).

RESULTS

Of 1491 patients randomly assigned to treatment, 4.9% (duloxetine, n = 45; placebo, n = 28) were >or= 65 years old. Compared with placebo-treated patients, duloxetine-treated patients experienced significantly greater improvements on the HAMA-total (p = 0.029), the HAMA-psychic anxiety factor (p = 0.034), HADS-anxiety (p = 0.049) and -depression scales (p = 0.026), but not the HAMA somatic anxiety factor (p = 0.074). Nausea was reported significantly more often in duloxetine-treated patients (30.0% vs. 7.1%, p = 0.023); duloxetine-treated patients experienced greater weight loss (p = 0.018). More duloxetine-treated patients discontinued treatment due to an adverse event (22.2% vs. 0%; p = 0.006).

CONCLUSION

Duloxetine was effective in an elderly patient subset with GAD, although there was a high rate of discontinuations due to adverse events.