Physical symptoms in primary care. Predictors of psychiatric disorders and functional impairment

OBJECTIVE: To examine how the type and number of physical symptoms reported by primary care patients are related to psychiatric disorders and functional impairment. DESIGN: Outpatient mental health survey. SETTING: Four primary care clinics. PATIENTS: One thousand adult clinic patients, of whom 631 were selected randomly or consecutively and 369 by convenience. MAIN OUTCOME MEASURES: Psychiatric disorders as determined by the Primary Care Evaluation of Mental Disorders procedure; the presence or absence of 15 common physical symptoms and whether symptoms were somatoform (ie, lacked an adequate physical explanation); and functional status as determined by the Medical Outcomes Study Short-form General Health Survey. RESULTS: Each of the 15 common symptoms was frequently somatoform (range, 16% to 33%). The presence of any physical symptom increased the likelihood of a diagnosis of a mood or anxiety disorder by at least twofold to three-fold, and somatoform symptoms had a particularly strong association with psychiatric disorders. The likelihood of a psychiatric disorder increased dramatically with increasing numbers of physical symptoms. The prevalence of a mood disorder in patients with 0 to 1, 2 to 3, 4 to 5, 6 to 8, and 9 or more symptoms was 2%, 12%, 23%, 44%, and 60%, respectively, and the prevalence of an anxiety disorder was 1%, 7%, 13%, 30%, and 48%, respectively. Finally, each physical symptom was associated with significant functional impairment; indeed, the number of physical symptoms was a powerful correlate of functional status. CONCLUSIONS: The number of physical symptoms is highly predictive for psychiatric disorders and functional impairment. Multiple or unexplained symptoms may signify a potentially treatable mood or anxiety disorder.