Anxiety and caffeine consumption in people with anxiety disorders.

Forty-three anxiety disorder patients (DSM-III) who completed the Hopkins Symptom Checklist (SCL-90-R) and a caffeine questionnaire were compared to 124 medical inpatients. Eighty-four percent of the anxious patients were low caffeine consumers (0-249 mg/day) compared to 41% of medical inpatients; 65% of anxiety patients consumed less than 100 mg/day. In anxiety patients, there were no significant correlations between subscale scores of the SCL-90-R and amount of caffeine consumption. Patients who consumed less than 100 mg/day did not differ on anxiety subscale scores of the SCL-90-R from those who consumed more. However, patients who reported becoming anxious in response to drinking coffee had higher SCL-90-R anxiety subscale scores than patients who did not, even though their daily consumption was not different. It appears that anxiety disorder patients have increased caffeine sensitivity which leads to decreased consumption.