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Effects of night shifts in bipolar disorders and extreme morningness
Robert Meyrer1, Joachim Demling, Johannes Kornhuber
1Department of Psychiatry and Psychotherapy, Centre for Sleep Medicine, University Hospital Erlangen, Erlangen, Germany.
Background:
Night work and shift work scenarios are increasing in modern society. Instability in the sleep-wake rhythm is an important risk factor for triggering episodes of bipolar disorder. Extreme chronotype has negative effects on shift work ("shift-worker syndrome"). Effects of night or shift work on patients with bipolar disorder and extreme chronotype are not well understood.
Case Report:
A patient with bipolar II disorder and extreme morning type followed a stable work schedule for a significant period of time, maintaining a stable mood. After changing to a night-shift schedule, depressive symptoms developed. When the night-shift schedule was stopped, her mental state normalised.
Conclusions:
This case highlights the possibility of a sensitizing role of chronotype in triggering episodes of bipolar disorder after the sleep-wake rhythm has been disrupted by night work or shift work. The evaluation of a person's capability to perform night work or shift work should take into account psychiatric disorders and chronotype as well as physical conditions.
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