NEW YORK - In a study of patients seen at primary care clinics, nearly 20 percent had at least one anxiety disorder and 41 percent of these patients were receiving no treatment.

Dr. Kurt Kroenke, from the Regenstrief Institute in Indianapolis, and colleagues assessed the prevalence and treatment of anxiety disorder by surveying and interviewing 965 patients randomly selected from 15 primary care clinics in the US.

Overall, 19.5 percent of patients had at least one anxiety disorder. The most common disorder was posttraumatic stress disorder, noted in 8.6 percent of patients, followed by generalized anxiety disorder in 7.6 percent, panic disorder in 6.8 percent, and social anxiety disorder in 6.2 percent.

Diagnosis of an anxiety disorder was associated with worse functional status, more disability days, and more trips to the doctor, the researchers note in their report in the Annals of Internal Medicine.

As noted, 41 percent of patients with an anxiety disorder were currently receiving no treatment.

Kroenke and colleagues developed a brief 7-item questionnaire, called the Generalized Anxiety Disorder (GAD)-7 scale, which they say doctors can use to easily spot patients with anxiety disorder.

The GAD-7 was highly sensitive and specific in detecting all four anxiety disorders studied, the researchers note.

SOURCE: Annals of Internal Medicine, March 6, 2007.