Generalized anxiety disorder
GAD
Research on the relationship between persistent worry across areas of life and everyday functioning.
Research question
What similarities and differences emerge when several countries track the relationship between worry and everyday functioning using the same methods?
Findings
Controlling worry and functional impairment
NICE guidance considers repeated worry about several issues, difficulty controlling it, and the degree of distress and functional impairment.
Interviews across 26 countries
An analysis of 147,261 adults in the WHO World Mental Health Surveys linked generalized anxiety disorder to difficulty carrying out everyday roles and to co-occurring mood and other anxiety disorders.
GAD-7 validation in primary care
At 15 US primary care clinics, 2,740 adults completed a questionnaire and 965 also completed an independent telephone interview with a mental health professional. Higher GAD-7 scores were associated with greater impairment across multiple domains.
Generalized anxiety outcomes in a primary care trial
A diagnosis-specific analysis of the CALM randomized trial across 17 clinics included 549 patients whose primary diagnosis was generalized anxiety disorder. The coordinated care group had lower anxiety severity scores than the usual-care group at 6, 12, and 18 months.
Genomic study of a combined anxiety phenotype
A genome-wide analysis across 36 cohorts compared 122,341 cases and 729,881 controls of European ancestry. It found 58 loci associated with a combined phenotype that included generalized anxiety disorder and four other anxiety disorders.
Twelve-year recovery and recurrence in a clinical sample
In the multicenter Harvard/Brown observational study, 179 participants had generalized anxiety disorder at intake. Survival analysis estimated a 58% cumulative probability of recovery over 12 years. Among those who recovered, the estimated cumulative probability of recurrence was 45% at the end of follow-up. Treatment was naturalistic in this clinical sample.
GAD-7 accuracy across languages and settings
A review covered 48 studies with 19,228 participants from 27 countries. In the 35 studies in the primary GAD-7 analysis for generalized anxiety disorder, pooled sensitivity at a cutoff of 10 or the closest available threshold was 0.64 (95% CI 0.56–0.72), and specificity was 0.91 (0.87–0.93). Accuracy varied substantially across studies.
Limitations
The survey used a single interview to collect retrospective reports of symptoms and onset, limiting its ability to distinguish persistent illness from recurrent episodes.
Original sources
Generalised anxiety disorder and panic disorder in adults: management (CG113)
National Institute for Health and Care Excellence
Cross-sectional Comparison of the Epidemiology of DSM-5 Generalized Anxiety Disorder Across the Globe
Ayelet Meron Ruscio et al.
A brief measure for assessing generalized anxiety disorder: the GAD-7
Robert L. Spitzer et al.
Disorder-specific impact of coordinated anxiety learning and management treatment for anxiety disorders in primary care
Michelle G. Craske et al.
Genome-wide association study of major anxiety disorders in 122,341 European-ancestry cases identifies 58 loci and highlights GABAergic signaling
Nora I. Strom et al.
Influence of psychiatric comorbidity on recovery and recurrence in generalized anxiety disorder, social phobia, and panic disorder: a 12-year prospective study
Steven E. Bruce et al.
Generalized Anxiety Disorder 7-item (GAD-7) and 2-item (GAD-2) scales for detecting anxiety disorders in adults
Zekeriya Aktürk et al.