Long-term pharmacological treatment of generalized anxiety disorder

Generalized anxiety disorder (GAD) is one of the most common anxiety disorders and has a poor prognosis, although it is often thought to be a minor complaint. This disorder has a chronic course of 5-15 years and longer. Long-term treatment with the commonly used benzodiazepines is controversial because of concerns over tolerance and dependence. We performed a thorough search of the literature for clinical trials of a duration of over 2 months conducted in patients with generalized anxiety disorder in order to identify any successful long-term treatment of this disorder. Only eight long-term reports of studies conducted in well-defined homogeneous groups of patients diagnosed with generalized anxiety disorder were found with the methodology of these studies presenting a number of limiting factors. The results are inconclusive and no reference drug could be identified. In addition, an adequate evaluation of the long-term treatment of GAD has not yet been performed.     

普瑞巴林治疗广泛性焦虑障碍的疗效与安全性的系统评价

目的系统评价普瑞巴林治疗广泛性焦虑障碍(GAD)的临床疗效和安全性。方法电子检索CENTRAL、Pubmed、EMbase和中国生物文献数据库文献(CBM),全面收集普瑞巴林治疗GAD的随机对照试验(RCTs),采用Cochrane系统评价方法评价纳入RCTs的方法学质量后,采用RevMan 5.1.4软件对提取的数据进行分析。结果纳入7个RCTs,共2 410例患者。与安慰剂相比,普瑞巴林150 mg·d~(-1)治疗GAD有效率无统计学差异[RR=1.32,95%CI(0.98,1.79),P=0.07],普瑞巴林固定剂量200～450 mg·d~(-1)[RR=1.60,95%CI(1.34,1.93),P<0.01]、600 mg·d~(-1)[RR=1.42,95%CI(1.18,1.70),P=0.000 2]以及可变剂量组[RR=1.25,95%CI(1.06,1.49),P=0.01]有效率差异均有统计学意义。与安慰剂组相比,普瑞巴林固定剂量组150～450 mg·d~(-1)以及可变剂量组因不良反应退出试验人数差异无统计学意义(分别为P=0.26,P=0.12);而普瑞巴林600 mg·d~(-1)组因不良反应退出试验人数差异有统计学意义[RR=1.76,95%CI(1.16,2.68),P=0.008]。结论普瑞巴林200～450 mg·d~(-1)治疗GAD有效且安全性好。     

Adjunctive therapy with pregabalin in generalized anxiety disorder patients with partial response to SSRI or SNRI treatment

This study evaluated the efficacy of adjunctive pregabalin versus placebo for treatment of patients with generalized anxiety disorder (GAD) who had not optimally responded to previous or prospective monotherapies. This was a phase 3, randomized, double-blind, placebo-controlled study. Patients diagnosed with GAD who had a historical and current lack of response to pharmacotherapy [Hamilton Anxiety Rating Scale (HAM-A) of ≥ 22 at screening] were randomized to adjunctive treatment with either pregabalin (150-600 mg/day) or placebo. The primary outcome measure was the change in HAM-A total scores after 8 weeks of combination treatment. Adverse events were regularly monitored. Randomized patients (N=356) were treated with pregabalin (n=180) or placebo (n=176). Mean baseline HAM-A scores were 20.7 and 21.4, respectively. After treatment, the mean change in HAM-A was significantly greater for pregabalin compared with placebo (-7.6 vs. -6.4, respectively; P<0.05). HAM-A responder rates (≥ 50% reduction) were significantly higher for pregabalin (47.5%) versus placebo (35.2%; P=0.0145). The time-to-sustained response favored pregabalin over placebo (P=0.014). Adverse events were consistent with previous studies and discontinuations were infrequent for pregabalin (4.4%) and placebo (2.3%). The study was discontinued early after an interim analysis. The results indicate that adjunctive pregabalin is an efficacious therapy for patients with GAD who experience an inadequate response to established treatments.     

Efficacy of pregabalin in depressive symptoms associated with generalized anxiety disorder: A pooled analysis of 6 studies

Epidemiological evidence supports comorbidity of generalized anxiety disorder (GAD) and major depressive disorder (MDD) or dysthymia, and its association with significant disability. As pregabalin, a new ₂-δ anxiolytic treatment for GAD, unlike most other licensed treatments for GAD has not undergone investigation in patients with MDD, we examined its efficacy in depressive symptoms associated with GAD, through a post-hoc analysis of the existing clinical trial database. The results provide consistent evidence that in patients with GAD pregabalin reduced associated symptoms of depression. This was seen in the 150 mg/day, 300–450 mg/day and 600 mg/day dosing groups. Even in subjects with more prominent depressive symptoms, pregabalin remained effective for both sub-syndromal depression and GAD symptoms, with pregabalin 300–450 mg/day demonstrating the most beneficial response. In conclusion, pregabalin, an alternative treatment option for GAD with a novel mechanism of action, also demonstrated efficacy in treating depressive symptoms typically encountered in GAD patients.     

Efficacy of pregabalin in generalized social anxiety disorder: results of a double-blind, placebo-controlled, fixed-dose study

The objective of this study was to evaluate the efficacy and tolerability of pregabalin for the treatment of generalized social anxiety disorder (SAD). Patients with generalized SAD, who met the Diagnostic and Statistical Manual of Mental Disorders (fourth edition) criteria (total N=329), were randomly assigned to 11 weeks of double-blind treatment with fixed daily doses of either pregabalin (300, 450, and 600(mg) or placebo. The treatment with pregabalin (600(mg) was associated with a significantly greater mean reduction in the Liebowitz Social Anxiety Scale total score, from baseline to endpoint, compared with placebo (-29.8 vs. -19.7; P= 0.0099), whereas reduction on pregabalin (300(mg, -20.2) and pregabalin (450(mg, -25.5) was not significant Treatment with pregabalin (600(mg) was also associated with a significantly greater improvement than placebo on the fear and avoidance subscales of the Liebowitz Social Anxiety Scale, as well as the majority of other secondary measures. Onset of improvement occurred by week 1 in the pregabalin 600-mg dose group. The most common adverse events on all three doses of pregabalin were somnolence and dizziness. Consistent with a previous study, the results of this study suggest that the 600-mg dose of pregabalin per day may be efficacious in the treatment of SAD.     

A meta-analytic review of the efficacy of drug treatment in generalized anxiety disorder

A meta-analytic review of the efficacy of pharmacological treatment in generalized anxiety disorder was conducted. The main substance classes were compared: benzodiazepines and azapirones. The impact of methodological variables was investigated such as sample size and use of a placebo run-in. After a comprehensive literature search to May 2002 (via databases, hand search, secondary sources, internet, contact of researchers, and pharmaceutical companies), the results of 48 studies were integrated. Weighted Hedges g was computed and a random-effects analysis was done. Effect sizes were computed for anxiety, depression, and clinical significance. Sensitivity analyses were conducted. Pharmacotherapy was superior to placebo in all symptom categories. Azapirones and benzodiazepines were equally effective. Compliance (as measured by dropout rate) was higher for benzodiazepines. Only sample size was significantly associated with effect size. Pharmacotherapy, especially benzodiazepines and azapirones, is effective in the short-term treatment of patients with generalized anxiety disorder. There was no superiority of 1 drug class in reducing symptomatology.     

Agomelatine in treating generalized anxiety disorder

Introduction: Generalized anxiety disorder (GAD) is a chronic and disabling disorder with a lifetime prevalence of 4.3 – 5.9% in the general population. Many drug and non-drug treatments have been shown to be effective in the treatment of GAD, including benzodiazepines, antidepressants (selective serotonin reuptake inhibitors, serotonin noradrenaline reuptake inhibitors and tricyclic antidepressants), anticonvulsants, azapirones, antihistamines, atypical antipsychotics, complementary/alternative medicine, psychotherapy and Internet-based services. Agomelatine is an antidepressant approved by the European Agency; it is a melatonergic agonist (MT1 and MT2 receptors) and a 5-HT_2C antagonist indicated in the treatment of major depressive episodes.

Areas covered: The present article looks at the short-term efficacy of Agomelatine assessed in two short-term placebo-controlled studies. It also looks at the long-term efficacy evaluated in one relapse prevention study.

Expert opinion: Agomelatine is an effective treatment option for both GAD and somatic anxiety. The trial, which includes an escitalopram arm, shows comparable efficacy in GAD between both antidepressants, whereas the restoration of sleep was significantly better with agomelatine. The low discontinuation rate illustrates the good tolerability and lab results show a low incidence of transient elevations in liver enzymes. Whereas uptitrated patients on a 50 mg dose have a lower chance of reaching the desired outcome than the lower 25 mg dose, those reaching this outcome have a better chance of treatment continuation.     

Efficacy of pregabalin and venlafaxine-XR in generalized anxiety disorder: results of a double-blind, placebo-controlled 8-week trial

The objective of this study was to evaluate the anxiolytic efficacy, and speed of onset of efficacy, of pregabalin (PGB) and venlafaxine-XR (VXR) in patients with generalized anxiety disorder (GAD). In this double-blind trial, outpatients, ages 18-65 years, who met Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria for GAD were randomized to 8 weeks of flexible-dose treatment with PGB (300-600 mg/day), VXR (75-225 mg/day), or placebo (PBO). The intent-to-treat sample consisted of 121 patients on PGB [least square (LS) mean ± SE baseline Hamilton Anxiety Rating Scale (HAM-A), 27.6 ± 0.4], 125 patients on VXR (baseline HAM-A, 27.4 ± 0.4), and 128 patients on PBO (baseline HAM-A, 26.8 ± 0.4). Treatment with PGB was associated with a significantly greater LS mean change in the HAM-A total score at last observation carried forward endpoint versus PBO (-14.5 ± 0.9 vs. -11.7 ± 0.9; P = 0.028). Treatment with VXR was not significant versus PBO at endpoint (-12.0 ± 0.9; -11.7 ± 0.9; P =0.968). Treatment with PGB showed an early onset of improvement, with significantly greater LS mean change in the HAM-A by day 4 versus both PBO (-5.3 ± 0.5 vs. -3.4± 0.5; P = 0.008) and VXR (-2.9 ± 0.5; P = 0.0012). The proportion of patients reporting a severe adverse event was similar for PGB (9.1%) and PBO (7.8%), but higher for VXR (20.0%; P < 0.05). In conclusion, PGB was a safe and effective treatment of GAD, with a significantly earlier onset of anxiolytic activity than VXR.     

A randomized,double-blind,placebo-controlled,fixed-dose,multicenter study of pregabalin in patients with generalized anxiety disorder

Pregabalin is a novel compound under development for the treatment of several types of anxiety disorders. To obtain an initial evaluation of the efficacy and safety of pregabalin in the treatment of generalized anxiety disorder (GAD), we conducted a double-blind, fixed-dose, parallel-group, placebo and active-controlled multicenter 4-week study that compared 271 patients randomized to receive pregabalin 50 mg tid (N = 70), pregabalin 200 mg tid (N = 66), placebo (N = 67), or lorazepam 2 mg tid (N = 68), followed by a 1-week double-blind taper. The primary efficacy parameter was change from baseline to endpoint (last observation carried forward) in the Hamilton Anxiety Scale (HAM-A) total score; adjusted mean change scores on the HAM-A were significantly improved for pregabalin 200 mg tid (difference of 3.90 between drug and placebo; p = 0.0013 [ANCOVA], df = 252) and for lorazepam (difference of 2.35; p = 0.0483 [ANCOVA], df = 252), with the significant difference between the pregabalin 200 mg tid and placebo groups seen at week 1 of treatment (p = 0.0001 [ANCOVA], df = 238). Safety analysis, which included assessment of spontaneously reported adverse events, laboratory monitoring, and withdrawal symptoms, showed pregabalin to be generally well-tolerated. The most common adverse events seen with pregabalin 200 mg tid were somnolence and dizziness. They were usually mild or moderate in intensity and were often transient. Pregabalin-treated patients had a higher completion rate than lorazepam-treated patients. This study supports the hypothesis that pregabalin is effective and safe in short-term therapy for GAD. More studies are needed to determine the best dosing regimen to optimize efficacy and tolerability.     

文拉法辛治疗广泛性焦虑症

目的 :观察文拉法辛治疗广泛性焦虑症的临床疗效及不良反应。方法 :根据CCMD Ⅱ R诊断为广泛性焦虑症的 2 1例病人 ,男性 13例 ,女性 8例 ,年龄 33a±s 16a( 18～ 65a) ,病程 14mo± 12mo( 1～ 60mo) ,给文拉法辛 50mg·d- 1,po× 4wk。治疗前后每周进行HAMA ,TESS评定及常规的实验室检查。结论 :文拉法辛抗焦虑作用 ,1wk见效 ,4wk显效率达 76%。不良反应以口干、出汗、恶心、头痛等多见。结果 :文拉法辛治疗广泛性焦虑症疗效确切 ,不良反应轻微     

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.     

Paroxetine treatment of generalized anxiety disorder

Generalized anxiety disorder (GAD) is a prevalent and disabling anxiety disorder, conservatively believed to affect at least 5% of the general population. Cardinal symptoms of GAD include chronic and uncontrollable worry, anxiety, and tension, which result in difficulty fulfilling social, professional, and family roles. Treatment options include benzodiazepines, tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine XR. Because of the high comorbidity of GAD with other psychiatric disorders, pharmacologic therapy should possess both anxiolytic and antidepressive properties for best outcomes. The SSRIs are a good treatment option, and paroxetine is the best studied SSRI for GAD and the only SSRI to date approved by the US Food and Drug Administration for this indication. Results of randomized, controlled studies of paroxetine have demonstrated its efficacy in the short-term treatment of GAD, in achieving and sustaining full remission, and in preventing relapse. This article provides an overview of GAD and a discussion of studies of paroxetine treatment in this anxiety disorder.     

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.     

Switching from long-term benzodiazepine therapy to pregabalin in patients with generalized anxiety disorder: a double-blind, placebo-controlled trial

To evaluate the efficacy of pregabalin in facilitating taper off chronic benzodiazepines, outpatients (N = 106) with a lifetime diagnosis of generalized anxiety disorder (current diagnosis could be subthreshold) who had been treated with a benzodiazepine for 8-52 weeks were stabilized for 2-4 weeks on alprazolam in the range of 1-4 mg/day. Patients were then randomized to 12 weeks of double-blind treatment with either pregabalin 300-600 mg/day or placebo while undergoing a gradual benzodiazepine taper at a rate of 25% per week, followed by a 6-week benzodiazepine-free phase during which they continued double-blind study treatment. Outcome measures included ability to remain benzodiazepine-free (primary) as well as changes in Hamilton Anxiety Rating Scale (HAM)-A and Physician Withdrawal Checklist (PWC). At endpoint, a non-significant higher proportion of patients remained benzodiazepine-free receiving pregabalin compared with placebo (51.4% vs 37.0%). Treatment with pregabalin was associated with significantly greater endpoint reduction in the HAM-A total score versus placebo (-2.5 vs +1.3; p < 0.001), and lower endpoint mean PWC scores (6.5 vs 10.3; p = 0.012). Thirty patients (53%) in the pregabalin group and 19 patients (37%) in the placebo group completed the study, reducing the power to detect a significant difference on the primary outcome. The results on the anxiety and withdrawal severity measures suggest that switching to pregabalin may be a safe and effective method for discontinuing long-term benzodiazepine therapy.     

Efficacy of pregabalin in the treatment of generalized anxiety disorder: double-blind, placebo-controlled comparison of BID versus TID dosing

Pregabalin is a new anxiolytic that acts as a presynaptic inhibitor of the release of excessive levels of excitatory neurotransmitters by selectively binding to the alpha2-delta subunit of voltage-gated calcium channels. The current study evaluated the anxiolytic efficacy of BID versus TID dosing of pregabalin in patients with generalized anxiety disorder. Outpatients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition generalized anxiety disorder and having baseline Hamilton Anxiety (HAM-A) total scores > or =20 were randomized to 6 weeks of double-blind treatment with pregabalin 200 mg/d (BID; N = 78), 400 mg/d (BID; N = 89), or 450 mg/d (TID; N = 88) or placebo (N = 86). Mean improvement in HAM-A total score at last observation carried forward end point was significantly greater on pregabalin 200 (P = 0.006), 400 (P = 0.001), and 450 mg/d (P = 0.005) compared with placebo. Pairwise comparisons of BID versus TID dosing found no difference in HAM-A change score at end point. All 3 pregabalin dosage groups showed significantly greater efficacy versus placebo at end point on the HAM-A psychic and somatic anxiety factor scores. Improvement on both factors was rapid: significance versus placebo was achieved as early as the first assessment at week 1, with > or =30% reduction in HAM-A severity and equal or greater improvement for every subsequent visit in > or =38% of patients in all 3 pregabalin dosage groups (P < or = 0.001). Pregabalin was well tolerated, and despite the fixed-dose study design, discontinuations caused by adverse events ranged from 9% to 13%--comparable with that observed with placebo (8%). This study demonstrates that pregabalin is an effective treatment of generalized anxiety disorder, with BID dosing showing similar efficacy and comparable tolerability with TID dosing.     

Joint modeling of dizziness,drowsiness, and dropout associated with pregabalin and placebo treatment of generalized anxiety disorder

Dizziness and drowsiness are cited as being predictors of dropout from clinical trials for the medicine pregabalin. These adverse events are typically recorded daily on a four point ordinal scale (0 = none, 1 = mild, 2 = moderate, 3 = severe), with most subjects never reporting either adverse event. We modeled the dizziness, drowsiness, and dropout associated with pregabalin use in generalized anxiety disorder using piecewise Weibull distributions for the time to first non-zero dizziness or drowsiness score, after which the dizziness or drowsiness was modeled with ordinal regression with a Markovian element. Dropout was modeled with a Weibull distribution. Platykurtosis was encountered in the estimated random effects distributions for the ordinal regression models and was addressed with dynamic John–Draper transformations. The only identified predictor for the time to first non-zero dizziness or drowsiness score was daily titrated dose. Predictors for dropout included creatinine clearance and maximum daily adverse event score. Tolerance to adverse events over time was modeled by including a non-stationary component for the dizziness ordinal Markov regression while the piecewise Weibull distributions allowed a change point in the median time to first non-zero dizziness or drowsiness score.     

帕罗西汀联合阿普唑仑治疗广泛性焦虑症的疗效观察

目的探讨帕罗西汀联合阿普唑仑治疗广泛性焦虑症患者的疗效,关注其对焦虑和抑郁评分的影响,以期为临床工作提供帮助。方法收集本院诊治的广泛性焦虑症的患者80例,随机分为观察组（40例）与对照组（40例）,对照组单纯应用帕罗西汀治疗,观察组应用帕罗西汀联合阿普唑仑治疗,观察治疗对患者焦虑和抑郁评分的影响。结果观察组在治疗2、4、8周后对焦虑和抑郁的改善情况明显优于对照组,两组差异有统计学意义（P〈0.05）。结论帕罗西汀联合阿普唑仑治疗广泛性焦虑症患者的疗效明显,对焦虑和抑郁改善的效果理想,临床中可以积极应用。