INSOMNIA IN ANXIETY - SLEEP EEG CHANGES

Anxiety is often paired with sleep disturbances and both interact in a quite complex manner. Sleep (and vigilance) problems are often includ ed in the descriptive definition or in the diagnostic criteria for anx iety disorders. Nevertheless, if anxiety may cause sleep disturbances, it is also known that sleep deprivation may produce symptoms which fa ll within the symptom complex of anxiety. In this paper, some of the m ethodological issues encountered when studying sleep and anxiety are d iscussed. Polygraphic recordings of sleep in anxious patients have con sistently shown an increased sleep latency and, quite often, also exhi bited a reduced sleep time, a reduced total sleep time, less slow-wave sleep, a greater arousal index and an increased duration of wakefulne ss during sleep. From our own study, we also report anomalies of the f irst night cycle in anxious poor sleepers who are otherwise indistingu ishable from normal controls (with regard to the 'classical' sleep par ameters). We have also observed the large interindividual variability of numbers of sleep parameters in anxious people. The question of a po tential heterogeneity of the studied groups with regard to their clini cal presentation as well as their sleep profile has been raised throug h our research as well. It is apparent that strategies for exploring t he source of the potential heterogeneity of anxiety disorders are stil l needed.