NONORGANIC INSOMNIA IN GENERALIZED ANXIETY DISORDER .1. CONTROLLED-STUDIES ON SLEEP, AWAKENING AND DAYTIME VIGILANCE UTILIZING POLYSOMNOGRAPHY AND EEG MAPPING

Objective and subjective sleep and awakening quality were assessed by self-rating scales and visual analog scales, objective awakening quali ty was measured by a psychometric test Objective and subjective sleep and awakening quality as well as daytime vigilance of insomniac patien ts with generalized anxiety disorder (GAD) were investigated, as compa red with normal controls. Forty-four outpatients (25 females, 19 males ), aged 24-65 (mean 43) years, diagnosed with non-organic insomnia (IC D-10: F 51.0), related to mild GAD (F 41.1), with a Hamilton anxiety ( HAMA) score of 22 +/- 6 and a Zung self-rating anxiety (SAS) score of 37 +/- 6 were included. After 1 adaptation night, sleep induction, mai ntainance and architecture were measured objectively by polysomnograph y, subjective battery, and diurnal tiredness was measured by a 3-min v igilance-controlled EEG (V-EEG) and a 4-min resting EEG mapping. In po lysomnography patients demonstrated - as compared with normals - signi ficantly increased wake time during the total sleep period and more ea rly-morning awakening, decreased total sleep and sleep efficiency. Sub jective sleep quality was deteriorated as well, as were well-being, dr ive, mood, and wakefulness in the morning. In noopsychic performance, GAD patients did rather well in attention, concentration, attention va riability, and numerical memory, while fine-motor activity and reactio n time were deteriorated. In psychophysiology, critical nicker frequen cy was decreased in the morning, while muscle strength, blood pressure and pulse rate showed no differences. EEG mapping during the late mor ning hours (10.00-12.00 h) demonstrated hypervigilance in the V-EEG, w hile in the resting recording an increased sleep pressure was detected . The latter was correlated significantly to the SAS score, but less s o to the observer-rated Hamilton anxiety score. Our findings suggest t hat CNS hypervigilance and hyperarousal, as actual symptoms of GAD, le ad to nocturnal insomnia, which in turn may cause - as a consequence o f sleep pressure not slept off - diurnal tiredness.