ABSTRACT

Studies generally indicate that panic disorder patients have reduced heart rate variability (HRV), diminished vagal tone and relative sympathetic dominance. Despite a consistent profile of reduced HRV in PD patients during daytime assessments, sleep-based HRV studies have yielded inconsistent results. For this reason, we aimed to investigate cardiac autonomic function in PD patients using polysomnographic records.

15 non-medicated PD patients and 15 age- and sex-matched normal controls were studied on polysomnography on two consecutive nights. Data were extracted from the second night for analysis.

Patients showed poor sleep efficiency, increased the number of the awakenings, and longer sleep latency than controls. Comparison of time domain and frequency domain HRV parameters between PD patients and control subjects revealed that there were no statistically significant differences.

The results indicate that the sympathovagal balance might not be influenced in drug-free patients with panic disorder in the early stage of illness.

Keywords: Panic disorder, heart rate variability, autonomic nervous system, sleep, spectral analysis