POLYSOMNOGRAPHIC STUDY OF SLEEP IN PATIENTS WITH PANIC DISORDER AND PRIMARY INSOMNIA

Fifteen patients with a DSM-III-R diagnosis of panic disorder with or without agoraphobia and their age- and sex-matched patients with a DSM-III-R diagnosis of primary insomnia were examined for 3 consecutive nights of sleep in the laboratory. To measure anxiety und depression we used the appropriate Hamilton Scales (HAMA and HAMD). Despite significant differences in the sleep parameters with respect to the number of stage shifts, the number of nocturnal awakenings, stage 1 and the percentage of total REM-sleep only minimal differences between both diagnostic groups were found. Patients with panic disorder or primary insomnia showed a marked first-night-effect from night one to night three that was an adaptation to the research conditions found in the sleep laboratory. The first-night recordings differed from those of the third night by prolonged sleep onset latency, reduced total sleep time, disturbed sleep continuation, prolonged REM-latency and reduction in percentage of REM sleep. Differences in the first-night-effect could not be assessed between diagnostic groups. The polysomnographic findings support the hypothesis that in patients with panic disorder as well as in those with primary insomnia the observed sleep disturbances may be due to underlying, but not specific mechanisms, and probably also reflect marked inter-individual differences of sleep.