Published online by Cambridge University Press: 07 November 2014
What are the current recommendations for the long-term treatment of generalized anxiety disorder (GAD)? GAD is a common disorder with a lifetime prevalence of 4% to 7% in the general population. GAD is characterized by excessive, uncontrollable worry or anxiety about a number of events or activities that the individual experiences on more days than not over a 6-month period. Onset of GAD symptoms usually occurs during an individual's early twenties; however, high rates of GAD have also been seen in children and adolescents. The clinical course of GAD is often chronic, with 40% of patients reporting illness lasting >5 years. GAD is associated with pronounced functional impairment, resulting in decreased vocational function and reduced quality of life. Patients with GAD tend to be high users of outpatient medical care, which contributes significantly to healtcare costs. Currently, benzodiazepines and buspirone are prescribed frequently to treat GAD. Although both show efficacy in acute treatment trials, few long-term studies have been perform Benzodiazepines are not recommended for long-term treatment of GAD, due to associated development of tolerance, psychomotor impairment, cognitive and memory changes, physical dependence, and a withdrawal reaction on discontinuation. The antidepressant venlafaxine extended-release (XR) has received approval for the treatment of GAD in the United States and many other countries. Venlafaxine XR has demonstrated efficacy over placebo in two randomized treatment trials of 6 months' duration as well as in other acute trials. Paroxetine is the first of the selective serotonin reuptake inhibitors (SSRIs) to receive US approval for the treatment of GAD. Paroxetine demonstrated superiority to placebo in short-term trials, and investigations into the use of other SSRIs are ongoing. This suggests that other SSRIs, and serotonin and noradrenaline reuptake inhibitors, are likely to be effective in the treatment of GAD. Of the psychological therapies, cognitive-behavioral therapy (CBT) shows the greatest benefit in treating GAD patients. Treatment gains after a 12-week course of CBT may be maintained for up to 1 year. Currently, no guidelines exist for the long-term treatment of GAD.