Generalized anxiety disorder in adults: Epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis
- David Baldwin, MA, DM FRCPsych
David Baldwin, MA, DM FRCPsych
- Professor of Psychiatry and Head of Mental Health Group
- University of Southampton Faculty of Medicine
Generalized anxiety disorder (GAD) is characterized by excessive and persistent worrying that is hard to control, causes significant distress or impairment, and occurs on more days than not for at least six months. Other features include psychological symptoms of anxiety, such as apprehensiveness and irritability, and physical (or somatic) symptoms of anxiety, such as increased fatigue and muscular tension.
Effective treatments for generalized anxiety disorder include psychological interventions such as cognitive-behavioral therapy and applied relaxation, and medications including selective serotonin reuptake inhibitors and serotonin-norepinephrine reuptake inhibitors.
This topic addresses the epidemiology, pathogenesis, clinical manifestations, and diagnosis of generalized anxiety disorder. Pharmacotherapy and psychotherapy for generalized anxiety disorder are discussed separately. (See "Approach to treating generalized anxiety disorder in adults" and "Pharmacotherapy for generalized anxiety disorder in adults" and "Psychotherapy for generalized anxiety disorder in adults".)
Generalized anxiety disorder (GAD) is common in both community and clinical settings. Epidemiologic studies of nationally representative samples in the United States have found a lifetime prevalence of GAD of 5.1 percent [1,2] to 11.9 percent . A review of epidemiological studies in Europe found a 12-month prevalence of 1.7 to 3.4 percent , and a lifetime prevalence of 4.3 to 5.9 percent .
GAD is one of the most common mental disorders in primary care settings and is associated with increased use of health services . In a study of adult primary care patients in four Nordic countries, the rates of GAD were 4.1 to 6.0 percent among men, and 3.7 to 7.1 percent among women .
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- Biological factors
- Neuropsychological factors
- Developmental and personality factors
- Cognitive origins of excessive worrying
- CLINICAL MANIFESTATIONS
- Screening instrument
- Symptom severity assessment instrument
- Differential diagnosis
- - Depression
- - Hypochondriasis
- - Panic disorder
- - Adjustment disorder
- Obsessive compulsive disorder
- Separation anxiety disorder
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- SUMMARY AND RECOMMENDATIONS