Effect of a novel environment on resting heart rate in panic disorder.

Several studies have found higher resting heart rate among patients with panic disorder compared to healthy controls, whereas others have found no differences. It has been suggested that these differences may result from anticipatory anxiety. The purpose of this study was to compare the resting heart rates of 10 patients with panic disorder, 11 patients with social phobia, and 13 healthy controls during two consecutive visits to our laboratory. There were no significant differences between groups on resting heart rate on either day. However, patients with panic disorder did have significantly higher resting heart rates on day 1 versus day 2. This suggests that patients with panic disorder may experience greater anticipatory anxiety which is manifested in a higher resting heart rate than patients with social phobia or healthy controls. Implications for previous and future reports on resting heart rate measures in patients with panic disorder are discussed.