Autonomic Dysfunctions in Patients with Anxiety Throughout Therapy

Patterns of autonomic cardiovascular regulation were studied in patients with anxiety throughout the course of an intensive inpatient rehabilitation therapy at rest, and in response to an anxiety provocation, in order to measure reactivity changes. Patients had to meet the ICD-10 criteria: F40.0 (agoraphobia), F40.00 (agoraphobia without panic attacks), F40.01 (agoraphobia with panic attacks), or F41 (panic disorder). Thirty-eight patients (13 males, 25 females) were examined after recruitment (T1) and at the end of treatment (T2). Each laboratory session consisted of a resting baseline (5min) and two stress tests of 8min (presentation of word pairs with either neutral or with anxiety-related content). A continuous assessment of ECG, blood pressure, breathing pattern, and thoracic impedance allowed the calculation of heart rate variability (power spectra), baroreflex sensitivity, stroke volume, vascular compliance, and total peripheral resistance. In general, therapy had little impact on the parameters of autonomic cardiovascular regulation, neither on resting level nor on reactivity. Diminished baroreflex sensitivity values in our patients with anxiety were observed; in particular, 15% of the patients had values below 3ms/mmHg, which indicates an increased risk for cardiovascular mortality. Low baroreflex sensitivity in this group goes along with further changes within the cardiovascular system (higher heart rate, diminished heart rate variability, lower stroke volume, higher vascular compliance). This general effect describes altered sympathetic/parasympathetic balance and may be the consequence of illness-related changes in behavior. Our results suggest that a careful cardiovascular examination of patients with anxiety will detect patients with clinically significant cardiovascular alterations. This might lead to a more complex intervention in these patients including, for example, exercise training.