Self-medication is the most frequently suggested para- digm to explain the high rate of comorbidity between anxiety and substance use. Although anxiety disorders, including GAD, are common in alcoholic patients, pa- tients with GAD are less likely to self-medicate with al- cohol and other substances than are patients with panic disorder and social phobia. However, up to two-thirds of patients receiving treatment for alcohol problems re- port clinically significant anxiety, including GAD (Grant et al. 2005). In most cases GAD develops after the alcohol problem. Alcohol and other substance with- drawal states are indistinguishable from the autonomic symptoms of GAD. Prolonged exposure to alcohol and other substances can lead to the same gastrointestinal, acid-base, and sleep disturbances described by patients with GAD.
Conclusion
GAD is a challenging diagnostic and treatment di- lemma. Notwithstanding changing diagnostic criteria, epidemiological surveys suggest that the disorder is one of the most prevalent psychiatric conditions. While cli- nicians attempt to identify response patterns, course, and predictors of response in rigorous double-blind studies, neuroscientists focus on the neurochemistry and neuroanatomy of select features of DSM categories, such as the excessive worry seen among individuals with GAD. The synthesis of the results of basic and clinical neuroscience and DSM-based treatment and epidemi- ological studies will likely improve our understanding of the nature of GAD and lead to better treatment.
Key Clinical Points
• Generalized anxiety disorder is distinct and common, but the severe disability associated with it is still underappreciated.
• The diagnosis of GAD can be made reliably, even in the presence of many comor- bid conditions.
• The epidemiology and symptoms of GAD are likely to differ significantly by age and gender.
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Recommended Readings
Kessler RC, Berglund P, Demler O, et al: Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry 62:593–602, 2005
Moffitt TE, Harrington H, Caspi A, et al: Depression and generalized anxiety disorder: cumulative and sequential
comorbidity in a birth cohort followed prospectively to age 32 years. Arch Gen Psychiatry 64:651–660, 2007 Papp LA: Generalized anxiety disorder: evaluation and treat-
ment, in Treatment Companion to the DSM-IV-TR Case Book. Edited by Spitzer RL, First MB, Gibbon M, et al. Washington, DC, American Psychiatric Publishing, 2004, pp 137–142
Rickels K, Rynn M: Overview and clinical presentation of generalized anxiety disorder. Psychiatr Clin North Am 24:1–17, 2001
Spitzer RL, Kroenke K, Williams JB, et al: A brief measure for assessing generalized anxiety disorder: the GAD-7. Arch Intern Med 166:1092–1097, 2006
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