Subthreshold Generalized Anxiety Disorder Research Articles

Generalized anxiety and mild anxiety symptoms in U.S. military veterans: Prevalence, characteristics, and functioning

Generalized anxiety disorder (GAD) is a mental disorder characterized by excessive anxiety and worries that impair daily functioning. While prior work has documented the prevalence and correlates of GAD and subthreshold GAD (SGAD) in clinical samples, contemporary data on the epidemiology of anxiety symptoms are lacking, particularly in higher-risk populations such as military veterans. To address this gap, we analyzed data from a large, nationally representative sample of U.S. veterans to examine the: prevalence of probable GAD and mild anxiety symptoms measured using a brief screener; sociodemographic and military characteristics associated with anxiety symptoms; and psychiatric and functional correlates of anxiety symptoms. Results revealed that a total of 7.9% (95% confidence interval [CI] = 6.7–9.3%) and 22.1% (95%CI = 20.5–23.9%) of veterans screened positive for probable GAD and mild anxiety symptoms, respectively. Relative to veterans without anxiety symptoms, those with probable GAD and mild anxiety symptoms were younger, more likely to be female and racial/ethnic minorities, and more likely to have served 2+ deployments. Further, a “dose-response” association was observed between anxiety symptom severity and clinical correlates, with robust associations observed between probable GAD and poorer mental health, suicidal thoughts and behaviors, and functional impairment. Mild anxiety symptoms showed intermediate magnitude associations with these outcomes. Results of this study suggest that 3-of-10 U.S. veterans report anxiety symptoms. While the use of a brief screener to assess mild anxiety symptoms and probable GAD is limited, findings underscore the importance of a dimensional approach to assessing anxiety symptoms and associated clinical and functional characteristics in veterans.

A RANDOMIZED CONTROLLED TRIAL OF SELF-HELP GUIDED BY LAY PROVIDERS FOR GENERALIZED ANXIETY DISORDER IN OLDER ADULTS

Abstract Low use of professional help for anxiety disorders in older adults may be due in part to limited access to mental health services. Self-help guided by lay providers (LPs) could help improve access to treatment. This study evaluated the efficacy and long-term outcomes of self-help guided by LPs for generalized anxiety disorder (GAD) in older adults. Participants (≥ 60 years) with threshold or subthreshold GAD were randomly assigned to an intervention group (n = 75) or a wait-list control group (n = 75). Intervention group participants used a manual presenting readings and exercises based on principles of cognitive-behavioral therapy and received weekly support calls by LPs. Groups were similar in terms of sociodemographic characteristics and initially did not differ significantly on outcomes. At post-treatment, the intervention group had decreased significantly on various measures while the wait-list group remained stable: Generalized Anxiety Disorder 7-item (GAD-7): -4.8 vs -.03; Penn State Worry Questionnaire (PSWQ): -11.7 vs .07; Geriatric Anxiety Inventory (GAI): -5.3 vs -.07. Probability of having a diagnosis of threshold GAD decreased significantly more in the intervention group (79% to 16% vs 74% to 53%). Intervention group scores on the GAD-7, the PSWQ, and the GAI as well as probability of having a diagnosis of threshold GAD remained stable at 6- and 12-month follow-ups. Results provide evidence of the efficacy of self-help guided by LPs for GAD in older adults as well as of the maintenance of improvement following this treatment.

P158: Efficacy of a self-help cognitive-behavioral therapy (GSH-CBT) guided by lay providers for generalized anxiety disorder (GAD) in older adults: preliminary results

Background:Only a small proportion of older adults with generalized anxiety disorder (GAD) seek professional help. One reason is the lack of access to mental health professionals licensed to provide psychotherapy. One way to improve access to psychotherapy is through guided self- help (GSH). GSH based on the principles of cognitive-behavior therapy (GSH-CBT) can be guided by trained lay providers (LPs). The purpose of this poster is to report preliminary results from a multisite randomized controlled trial testing the efficacy of a GSH-CBT guided by LPs for GAD in older adults.Methods:The sample included 150 participants (≥ 60 years old) with a diagnosis of threshold or subthreshold GAD randomly assigned to: 1) GSH-CBT guided by LPs (n = 75) or 2) waiting list (n = 75). The GSH-CBT lasted 15 weeks. Participants used a manual presenting weekly reading and at-home exercises. They also received weekly support calls (30 minutes maximum) by LPs (undergraduate psychology students) supervised by psychologists. Repeated-measures regression models were used to compare changes in the groups before and after 15 weeks on three outcomes: severity of GAD symptoms (Generalized Anxiety Disorder 7-item; GAD-7), tendency to worry (Penn State Worry Questionnaire; PSWQ), and level of anxiety (Geriatric Anxiety Inventory; GAI).Results:At the first assessment, both groups were similar in terms of age, sex, level of education, marital status, occupation, and did not differ significantly on outcomes. The GSH- CBT group decreased significantly on all three outcomes (GAD-7: -4.8, 95% CI [-5.7, -3.8], PSWQ: -11.7; 95% CI [-13.6, -9.9], GAI: -5.3 95% CI [-6.5, -4.1]) while the waiting list group remained stable over 15 weeks (GAD-7: -0.3, 95% CI [-1.2, 0.6], PSWQ: 0.7; 95% CI [-1.2, 2.5], GAI: -0.7 95% CI [-1.9, -0.5]).Conclusions:GSH-CBT guided by LPs appears to be an effective intervention for reducing severity of GAD symptoms, tendency to worry, and level of anxiety in older people with GAD. Further analyses will be conducted to test whether the intervention differs in efficacy between participants with a threshold vs. subthreshold GAD. The maintenance of long-term gains (6 and 12 months after the intervention) will also be tested.

Efficacy of Silexan in patients with anxiety disorders: a meta-analysis of randomized, placebo-controlled trials

IntroductionWe report on a meta-analysis of Silexan, a proprietary active substance produced from Lavandula angustifolia, in subthreshold anxiety, mixed anxiety and depressive disorder (MADD), and generalized anxiety disorder (GAD).MethodsThe present analyses are based on all currently completed 5 double-blind, randomized, placebo-controlled trials investigating Silexan in adult out-patients who received Silexan 1 × 80 mg/day or placebo for ten weeks according to random assignment (n = 1213). Efficacy was assessed based on the Hamilton Anxiety Rating Scale (HAMA), several anxiety self-rating scales, the Clinical Global Impression (CGI) scale, and the Short Form-36 (SF-36) health status questionnaire.ResultsAfter ten weeks’ treatment, Silexan was significantly superior to placebo in reducing the HAMA total score (including the psychic and somatic anxiety sub-scores) and self-rated anxiety. Based on a ≥ 50% HAMA total score reduction, the responder rate ratio was 1.34 favoring Silexan, and the rate ratio of subjects much or very much improved according to the CGI was 1.51. Silexan was also significantly superior in improving the physical and mental health summary scores of the SF-36. There were no significant between-group differences concerning the occurrence of adverse events (AEs), serious AEs, and premature withdrawal due to AEs.ConclusionsThis meta-analysis demonstrates that Silexan exerts significant anxiolytic effects in subthreshold anxiety, GAD and MADD that were consistently reflected in investigator ratings and patient-reported outcomes, including improvement of health-related life-quality, while showing favorable tolerability and safety.

A randomized controlled feasibility trial of internet-delivered guided self-help for generalized anxiety disorder (GAD) among university students in India.

Online guided self-help may be an effective and scalable intervention for symptoms of generalized anxiety disorder (GAD) among university students in India. Based on an online screen for GAD administered at 4 Indian universities, 222 students classified as having clinical (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria) or subthreshold (Generalized Anxiety Disorder Questionnaire, Fourth Edition, score ≥ 5.7) GAD were randomly assigned to receive either 3 months of guided self-help cognitive-behavioral therapy (n = 117) or a waitlist control condition (n = 105). Guided self-help participants recorded high program usage on average across all participants enrolled (M = 9.99 hr on the platform; SD = 20.87). Intent-to-treat analyses indicated that participants in the guided self-help condition experienced significantly greater reductions than participants in the waitlist condition on GAD symptom severity (d = -.40), worry (d = -.43), and depressive symptoms (d = -.53). No usage variables predicted symptom change in the guided self-help condition. Participants on average reported that the program was moderately helpful, and a majority (82.1%) said they would recommend the program to a friend. Guided self-help appears to be a feasible and efficacious intervention for university students in India who meet clinical or subthreshold GAD criteria. The trial is registered with ClinicalTrials.gov (NCT02410265). (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Self-help guided by trained lay providers for generalized anxiety disorder in older adults: study protocol for a randomized controlled trial

BackgroundOnly a small proportion of older patients with generalized anxiety disorder (GAD) seek professional help. Difficulties in accessing treatment may contribute to this problem. Guided self-help based on the principles of cognitive-behavioral therapy (GSH-CBT) is one way of promoting access to psychological treatment. Moreover, because the therapist’s role in GSH-CBT is limited to supporting the patient, this role could be assumed by trained and supervised lay providers (LPs) instead of licensed providers. The main goal of this study is to evaluate the efficacy of GSH-CBT guided by LPs for primary threshold or subthreshold GAD in older adults.MethodsWe will conduct a multisite randomized controlled trial comparing an experimental group receiving GSH-CBT guided by LPs (n = 45) to a wait-list control group (n = 45). Treatment will last 15 weeks and will be based on a participant’s manual. Weekly telephone sessions with LPs (30 min maximum) will be limited to providing support. Data will be obtained through clinician evaluations and self-assessment questionnaires. Primary outcomes will be the tendency to worry and severity of GAD symptoms. Secondary outcomes will be anxiety symptoms, sleep difficulties, functional deficit, diagnosis of GAD, and cognitive difficulties. For the experimental group, measurements will take place at pre- and post-treatment and at 6 and 12 months post-treatment. For the control group, three evaluations are planned: two pre-treatment evaluations (before and after the waiting period) and after receiving treatment (post-treatment). The efficacy of GSH-CBT will be established by comparing the change in the two groups on the primary outcomes.DiscussionThis project will provide evidence on the efficacy of a novel approach to treat GAD in older adults. If effective, it could be implemented on a larger scale and provide many older adults with much needed mental health treatment through an expanded workforce.Trial registrationThe trial was registered at ClinicalTrials.gov, number NCT03768544, on December 7, 2018.

Suicidality in Subjects With Anxiety or Obsessive-Compulsive and Related Disorders: Recent Advances.

Historically, anxiety disorders have not been considered as important determinants of suicide, but in the last years, many works have challenged this assumption. Here, we will review the available evidence on the relationship between suicide and anxiety disorders (e.g., obsessive-compulsive disorder, post-traumatic stress disorder, generalized anxiety disorder, panic disorder, and body dysmorphic disorder), with special emphasis on findings published in the last years. Overall, anxiety disorders increase the risk of suicide. Specifically, 16% of patients with social anxiety disorder reported suicidal ideation in the previous month, and 18% of them had a history of suicide attempts. Similarly, in patients with panic disorder, suicidal ideation prevalence ranged between 17 and 32%, and 33% of them had a history of suicide attempts. Generalized anxiety disorder (GAD) was the most frequent anxiety disorder in completed suicides (present in 3% of people who committed suicide) and also subthreshold GAD was clearly linked to suicide ideation. Post-traumatic stress disorder was positively associated with suicidal ideation, and in patients with obsessive-compulsive disorder, suicide ideation rates ranged from 10 to 53% and suicide attempts from 1 to 46%. Body dysmorphic disorders presented a suicide ideation prevalence of about 80%. Suicide risk is increased in subjects with anxiety disorder. This risk is higher in the presence of comorbidities, but it is not clear whether it is independent from such comorbidities in some disorders.

Psychiatric comorbidity does not only depend on diagnostic thresholds: An illustration with major depressive disorder and generalized anxiety disorder

BackgroundHigh rates of psychiatric comorbidity are subject of debate: to what extent do they depend on classification choices such as diagnostic thresholds?Aims/objectivesTo investigate the influence of different thresholds on rates of comorbidity between major depressive disorder (MDD) and generalized anxiety disorder (GAD).MethodsPoint prevalence of comorbidity between MDD and GAD was measured in 74,092 subjects from the general population according to DSM-IV-TR criteria. Comorbidity rates were compared for different thresholds by varying the number of necessary criteria from ≥ 1 to all 9 symptoms for MDD, and from ≥ 1 to all 7 symptoms for GAD.ResultsAccording to DSM-thresholds, 0.86% had MDD only, 2.96% GAD only and 1.14% both MDD and GAD (Odds Ratio [OR] 42.6). Lower thresholds for MDD led to higher rates of comorbidity (1.44% for ≥ 4 of 9 MDD-symptoms, OR 34.4), whereas lower thresholds for GAD hardly influenced comorbidity (1.16% for ≥ 3 of 7 GAD-symptoms, OR 38.8). Specific patterns in the distribution of symptoms within the population explained this finding: 37.3% of subjects with core criteria of MDD and GAD reported subthreshold MDD symptoms, whereas only 7.6% reported subthreshold GAD symptoms.ConclusionsLower thresholds for MDD increased comorbidity with GAD, but not vice versa, owing to specific symptom patterns in the population. Generally, comorbidity rates result from both empirical symptom distributions and classification choices and cannot be reduced to either of these exclusively. This insight invites further research into the formation of disease concepts that allow for reliable predictions and targeted therapeutic interventions.Disclosure of interestThe authors have not supplied their declaration of competing interest.

The Feasibility, Acceptability, and Efficacy of Delivering Internet-Based Self-Help and Guided Self-Help Interventions for Generalized Anxiety Disorder to Indian University Students: Design of a Randomized Controlled Trial.

BackgroundGeneralized anxiety disorder (GAD) is one of the most common mental disorders among university students; however, many students go untreated due to treatment costs, stigma concerns, and limited access to trained mental health professionals. These barriers are heightened in universities in India, where there are scant mental health care services and severe stigma surrounding help seeking.ObjectiveTo evaluate the feasibility, acceptability, and efficacy of Internet-based, or “online,” cognitive behavioral therapy (CBT)-based unguided and guided self-help interventions (using the programs GAD Online and Lantern, respectively) to reduce GAD symptoms in students with clinical and subthreshold GAD and, ultimately, reduce the prevalence and incidence of GAD among the student population.MethodsStudents will be recruited via 3 colleges in Hyderabad, India, and referred for a campus-wide online screening. Self-report data will be collected entirely online. A total of 300 qualifying students will be randomized in a 1:1:1 ratio to receive GAD Online, Lantern, or to be in a wait-list control condition, stratified by clinical and subthreshold GAD symptomatology. Students will complete a postintervention assessment after 3 months and a follow-up assessment 6 months later, at which point students in the wait-list control condition will receive one of the programs. The primary outcome is GAD symptom severity at 3 months postintervention. Secondary outcomes include GAD caseness at 9 months, other anxiety and depression symptoms, self-efficacy, and functional measures (eg, sleep, social functioning) at 3 and 9 months, respectively. Primary analyses will be differences between each of the intervention groups and the wait-list control group, analyzed on an intention-to-treat (ITT) basis using mixed-design ANOVA.ResultsThe study commenced in February 2015. The sample was recruited over a 3-week period at each college. The trial is expected to end in December 2015.ConclusionsThis trial will be the first to evaluate the use of Internet-based CBT programs compared with a wait-list control group for the treatment of GAD among students in Indian universities. If effective, these programs have the potential to reduce the mental health care treatment gap by providing readily accessible, private, and cost-effective evidence-based care to students with GAD who do not currently receive the treatment they need.Trial RegistrationClinicalTrials.gov NCT02410265 http://clinicaltrials.gov/ct2/show/NCT02410265 (Archived by WebCite at http://www.webcitation.org/6ddqH6Rbt).

PSYCHIATRIC COMORBIDITY DOES NOT ONLY DEPEND ON DIAGNOSTIC THRESHOLDS: AN ILLUSTRATION WITH MAJOR DEPRESSIVE DISORDER AND GENERALIZED ANXIETY DISORDER

High rates of psychiatric comorbidity are subject of debate: To what extent do they depend on classification choices such as diagnostic thresholds? This paper investigates the influence of different thresholds on rates of comorbidity between major depressive disorder (MDD) and generalized anxiety disorder (GAD). Point prevalence of comorbidity between MDD and GAD was measured in 74,092 subjects from the general population (LifeLines) according to Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) criteria. Comorbidity rates were compared for different thresholds by varying the number of necessary criteria from ≥ 1 to all nine symptoms for MDD, and from ≥ 1 to all seven symptoms for GAD. According to DSM thresholds, 0.86% had MDD only, 2.96% GAD only, and 1.14% both MDD and GAD (odds ratio (OR) 42.6). Lower thresholds for MDD led to higher rates of comorbidity (1.44% for ≥ 4 of nine MDD symptoms, OR 34.4), whereas lower thresholds for GAD hardly influenced comorbidity (1.16% for ≥ 3 of seven GAD symptoms, OR 38.8). Specific patterns in the distribution of symptoms within the population explained this finding: 37.3% of subjects with core criteria of MDD and GAD reported subthreshold MDD symptoms, whereas only 7.6% reported subthreshold GAD symptoms. Lower thresholds for MDD increased comorbidity with GAD, but not vice versa, owing to specific symptom patterns in the population. Generally, comorbidity rates result from both empirical symptom distributions and classification choices and cannot be reduced to either of these exclusively. This insight invites further research into the formation of disease concepts that allow for reliable predictions and targeted therapeutic interventions.

Classification models for subthreshold generalized anxiety disorder in a college population: Implications for prevention

Generalized anxiety disorder (GAD) is one of the most common psychiatric disorders on college campuses and often goes unidentified and untreated. We propose a combined prevention and treatment model composed of evidence-based self-help (SH) and guided self-help (GSH) interventions to address this issue. To inform the development of this stepped-care model of intervention delivery, we evaluated results from a population-based anxiety screening of college students. A primary model was developed to illustrate how increasing levels of symptomatology could be linked to prevention/treatment interventions. We used screening data to propose four models of classification for populations at risk for GAD. We then explored the cost considerations of implementing this prevention/treatment stepped-care model. Among 2489 college students (mean age 19.1 years; 67% female), 8.0% (198/2489) met DSM-5 clinical criteria for GAD, in line with expected clinical rates for this population. At-risk Model 1 (subthreshold, but considerable symptoms of anxiety) identified 13.7% of students as potentially at risk for developing GAD. Model 2 (subthreshold, but high GAD symptom severity) identified 13.7%. Model 3 (subthreshold, but symptoms were distressing) identified 12.3%. Model 4 (subthreshold, but considerable worry) identified 17.4%. There was little overlap among these models, with a combined at-risk population of 39.4%. The efficiency of these models in identifying those truly at risk and the cost and efficacy of preventive interventions will determine if prevention is viable. Using Model 1 data and conservative cost estimates, we found that a preventive intervention effect size of even 0.2 could make a prevention/treatment model more cost-effective than existing models of “wait-and-treat.”

Subthreshold and threshold DSM-IV generalized anxiety disorder in Singapore: Results from a nationally representative sample

Previous nationally representative studies have reported prevalence of DSM-IV generalized anxiety disorder (GAD). However, subthreshold and threshold GAD expressions remain poorly understood. The current study examined the prevalence, correlates and co-morbidity of a broader diagnosis of GAD in Singapore. The Singapore Mental Health Study (SMHS) was an epidemiological survey conducted in the population (N=6616) aged 18 years and older. The Composite International Diagnostic Interview version 3.0 (CIDI 3.0) was used to establish mental disorder diagnoses. The lifetime prevalence for subthreshold GAD (2.1%) and threshold GAD (1.5%) in the current sample was found to be lower than in Western populations. Younger age group, Indian ethnicity, previously married, chronic physical conditions, and being unemployed were associated with higher odds of having more severe expression of generalized anxiety. The relatively lower prevalence rate of subthreshold GAD expression suggests possible cultural interferences in the reporting and manifestation of anxiety symptomatology. Despite the low prevalence, significant impacts on functioning and comorbidity among subthreshold generalized anxiety cases indicate the importance of early treatment to ensure a better prognosis.

Clinical significance of worry and physical symptoms in late-life generalized anxiety disorder.

Worry is a hallmark feature of generalized anxiety disorder (GAD). However, age-related changes in symptom presentation raise questions about the clinical significance of these symptom clusters in later life. The aim of this study was to explore the relative contribution of worry and physical symptom frequency to clinical significance associated with late-life GAD. A sample of 637 self-reported worriers (aged 65 years and older) was extracted from Wave 1 of the National Epidemiological Survey of Alcohol and Related Conditions. Consistent with previous findings, we observed reductions in worry frequency and increases in physical symptom frequency with increasing age of participants. Physical symptoms, but not worry symptoms, distinguished older adults with clinical and sub-threshold GAD. Whereas physical symptom count was associated with distress, occupational, and functional disability, worry count was only associated with distress. Among self-reported worriers, worry frequency provides limited clinical utility over and above physical symptom frequency. These findings suggest that physical symptom frequency may become an increasingly important feature of GAD in later life.

Threshold and subthreshold generalized anxiety disorder in later life.

Symptoms and disorders of anxiety are highly prevalent among older adults; however, late-life anxiety disorders remain underdiagnosed. The objective of this study was to (1) estimate the prevalence of late-life threshold and subthreshold generalized anxiety disorder (GAD), (2) examine sociodemographic and health correlates associated with membership in these groups, (3) assess 3-year conversion rates of these groups, and (4) explore characteristics associated with 3-year conversion to GAD. Using Waves 1 and 2 of the National Epidemiological Survey of Alcohol and Related Conditions, 13,420 participants aged 55-98 years were included in this study. Subthreshold GAD was more highly prevalent than threshold GAD and was interposed between asymptomatic and GAD groups in terms of severity of health characteristics. Although most participants with subthreshold and threshold GAD were asymptomatic by Wave 2, differences in disability persisted. Subthreshold GAD at baseline was not a predictor of threshold GAD at follow-up. These findings suggest that late-life GAD should be conceptualized as a dimensional rather than categorical construct. The temporal stability of anxiety-associated disability further suggests that subthreshold GAD bears clinical significance. However, the suitability and efficacy of interventions for minimizing negative sequelae in this group remain to be determined.

Oral contraceptive use and psychiatric disorders in a nationally representative sample of women.

The purpose of this study is to examine the association between oral contraceptive use (any current use, duration, and type) and major depressive disorder (MDD), generalized anxiety disorder (GAD), and panic disorder (PD) in a nationally representative sample of women in the USA. Data were drawn from 1,105 women aged 20-39 in the National Health and Nutrition Examination Surveys from 1999 to 2004. The associations between self-reported use of oral contraceptives in the past year and DSM-IV diagnosed and subthreshold MDD, GAD, and PD in the past year were assessed comparing oral contraceptive users to all non-users, former users, and former long-term users. Women using oral contraceptives had a lower past-year prevalence of all disorders assessed, other than subthreshold MDD. When adjusted for confounders, women using oral contraceptives in the past year had significantly lower odds of subthreshold PD, compared to former users (odds ratio (OR) = 0.34, 95 % CI 0.14-0.84). Effects estimates were strongest for monophasic (versus multiphasic) oral contraceptive users. Hormonal contraceptive use was associated with reduced risk of subthreshold PD. A potential mental health benefit of hormonal contraceptives has substantial public health implications; prospective longitudinal studies are needed to confirm whether hormonal contraceptive use improves mental health.

The prevalence and burden of subthreshold generalized anxiety disorder: a systematic review.

BackgroundTo review the prevalence and impact of generalized anxiety disorder (GAD) below the diagnostic threshold and explore its treatment needs in times of scarce healthcare resources.MethodsA systematic literature search was conducted until January 2013 using PUBMED/MEDLINE, PSYCINFO, EMBASE and reference lists to identify epidemiological studies of subthreshold GAD, i.e. GAD symptoms that do not reach the current thresholds of DSM-III-R, DSM-IV or ICD-10. Quality of all included studies was assessed and median prevalences of subthreshold GAD were calculated for different subpopulations.ResultsInclusion criteria led to 15 high-quality and 3 low-quality epidemiological studies with a total of 48,214 participants being reviewed. Whilst GAD proved to be a common mental health disorder, the prevalence for subthreshold GAD was twice that for the full syndrome. Subthreshold GAD is typically persistent, causing considerably more suffering and impairment in psychosocial and work functioning, benzodiazepine and primary health care use, than in non-anxious individuals. Subthreshold GAD can also increase the risk of onset and worsen the course of a range of comorbid mental health, pain and somatic disorders; further increasing costs. Results are robust against bias due to low study quality.ConclusionsSubthreshold GAD is a common, recurrent and impairing disease with verifiable morbidity that claims significant healthcare resources. As such, it should receive additional research and clinical attention.

Threshold and subthreshold generalized anxiety disorder among US adolescents: prevalence, sociodemographic, and clinical characteristics

Threshold and subthreshold forms of generalized anxiety disorder (GAD) are highly prevalent and impairing conditions among adults. However, there are few general population studies that have examined these conditions during the early life course. The primary objectives of this study were to: (1) examine the prevalence, and sociodemographic and clinical characteristics of threshold and subthreshold forms of GAD in a nationally representative sample of US youth; and (2) test differences in sociodemographic and clinical characteristics between threshold and subthreshold forms of the disorder. The National Comorbidity Survey-Adolescent Supplement is a nationally representative face-to-face survey of 10,123 adolescents 13 to 18 years of age in the continental USA. Approximately 3% of adolescents met criteria for threshold GAD. Reducing the required duration from 6 months to 3 months resulted in a 65.7% increase in prevalence (5.0%); further relaxing the uncontrollability criterion led to an additional 20.7% increase in prevalence (6.1%). Adolescents with all forms of GAD displayed a recurrent clinical course marked by substantial impairment and co-morbidity with other psychiatric disorders. There were few significant differences in sociodemographic and clinical characteristics between threshold and subthreshold cases of GAD. Results also revealed age-related differences in the associated symptoms and clinical course of GAD. Findings demonstrate the clinical significance of subthreshold forms of GAD among adolescent youth, highlighting the continuous nature of the GAD construct. Age-related differences in the associated symptoms and clinical course of GAD provide further support for criteria that capture variation in clinical features across development.

Characteristics of subjects with comorbidity of symptoms of generalized anxiety and major depressive disorders and the corresponding threshold and subthreshold conditions in an Arab general population sample

SummaryBackgroundThere is controversy about differential meaningfulness between comorbid generalized anxiety disorder (GAD)/ major depressive disorder (MDD), the corresponding “pure” disorders and subthreshold conditions. We compared subjects who met DSM-IVTR criteria of symptoms and functional impairment for comorbid GAD/MDD, versus those with GAD, MDD, subthreshold conditions, and without significant symptoms. The comparison measures were socio-demographics, clinical severity, and quality of life (QOL).Material/MethodsParticipants (N=3155: 55.1% female, aged 16–87 yrs) were a general population sample of Kuwaitis who self-completed DSM-IVTR criteria-based questionnaires and the WHOQOL-BREF in 2006/7. We scrutinized the questionnaires and classified them into categories.ResultsOf the 273 GAD and 210 MDD cases, the prevalence of comorbidity among cases with GAD was 30.8%, and 40% among MDD. Of the 398 subthreshold GAD and 194 subthreshold MDD cases, 58 had subthreshold anxiety/depression comorbidity. Comorbid threshold GAD/MDD cases were significantly older, and more likely to be women, divorced and unemployed, compared with GAD and MDD. In all measures, the threshold GAD/MDD comorbidity was the severest condition. There was a monotonic decrease in QOL with increasing anxiety-depression symptoms. For the predictors of subjective QOL, the GAD/MDD comorbidity group differed markedly from the others.ConclusionsThe high prevalence of comorbidity and subthreshold conditions supports the recommendation to assess them routinely, regardless of the primary reason for consultation. Our findings support a dimensional model with comorbid GAD/MDD at the higher end of a continuum, and differing from the “pure” conditions by a later onset and predictors of subjective wellbeing.

Human and Economic Burden of GAD, Subthreshold GAD, and Worry in a Primary Care Sample

Generalized anxiety disorder (GAD) has been associated with significant impairment and estimates of human and economic burden associated with the disorder are substantial. Little has been done, however, to examine impairment associated with subthreshold presentations of the disorder in medically underserved populations. This study compared primary care patients with GAD (n=30), subthreshold GAD (n=21), worry (n=79), and no worry (n=199) on measures of human and economic burden. On measures of human burden, all three symptomatic groups reported poorer perceived physical health, greater stress, and sleep difficulty. Worried and subthreshold groups also reported lower social support. For economic burden, GAD and worry groups reported a greater number of prescription medications. However, when co-morbid depression was accounted for the effect was no longer significant. Groups did not differ on employment status, number of visits to the clinic in the last 90days, or physical health. Results are discussed in terms of identification, prevention, and intervention for GAD in primary care settings.

P01-160 - Efficacy and safety of silexan, a new, orally administered lavender oil preparation, in subthreshold anxiety disorder

A number of studies has been performed recently on the efficacy and tolerability of silexan, a novel preparation from lavender oil for oral use, in the treatment of anxiety disorders and related conditions with particular attention to subthreshold generalized anxiety disorder (GAD). Three randomized, double-blind clinical trials were identified which investigated the efficacy of silexan in subsynromal anxiety disorder (vs. placebo; 10 weeks’ treatment), in GAD (vs. lorazepam; 6 weeks), and in restlessness and agitation (vs. placebo; 10 weeks) according to DSM-IV and ICD-10 criteria. One open-label pilot study assessed the potential of the medicinal product in neurasthenia, posttraumatic stress disorder and somatization disorder (6 weeks). All trials assessed the participants’ anxiety levels using the Hamilton Anxiety Scale (HAMA) or the State Trait Anxiety Inventory (STAI) as well as measures of co-morbidity and clinical global impressions. Across all trials 280 patients were exposed to silexan 80 mg/day, 37 were treated with lorazepam 0.5 mg/day and 192 received placebo. Average within group HAMA total scores at baseline ranged between 24.7 and 27.1 points. Patients treated with silexan showed average HAMA total score decreases by between 10.4 ± 7.1 and 12.0 ± 7.2 points at week 6 and by between 11.8 ± 7.7 and 16.0 ± 8.3 points at week 10. In subthreshold GAD silexan was significantly superior to placebo, with a mean value difference of at least 4 points (lower bound of 95% confidence interval (CI)) after 10 weeks. In GAD silexan and lorazepam showed comparable HAMA total score reductions (90% CI for mean value difference: -2.3; 2.8 points). The decrease of anxiety levels was accompanied by a reduction of restlessness and co-morbidity, and by improvements in general well-being. The anxiolytic effect of silexan is superior to placebo and comparable to lorazepam in subthreshold and threshold GAD, respectively. The medicinal product also improved associated symptoms like restlessness, disturbed sleep and somatic complaints, and had a beneficial influence on general well-being and quality of life. Silexan may offer interesting perspectives particularly in the treatment of subthreshold GAD.