Generalized anxiety disorder. Epidemiology, impact of comorbidity, and natural history.

According to epidemiologic data collected over the last 5 years, GAD is a prevalent psychiatric disorder that is more chronic than most other psychiatric conditions. Excessive worry, which is the definitive diagnostic criterion, is accompanied by secondary psychic and somatic symptoms. GAD often coexists with other psychiatric conditions, which adds to the serious functional impairment caused when it occurs alone. However, even GAD results in substantial psychosocial impairment that is comparable to that caused by panic disorder, major depression, and other psychiatric disorders. Recognition of the need for long-term treatment of GAD is growing now that the medical community has realized that GAD is an independent disorder with an early age of onset and a chronic, unremitting course. Rarely do patients with GAD seek treatment for excessive worry. Rather, help-seeking behavior in this patient population is usually prompted by secondary symptoms. Continued research is imperative to achieve a better understanding of potential therapies for GAD, the reversibility of the disorder, and the impact of early, aggressive intervention on its course.