Sleep and circadian rhythms as possible trait markers of suicide attempt in bipolar disorders: An actigraphy study.

•Sleep and circadian rhythms disturbances are associated to history of suicide attempts.•Suicide attempt is associated with women gender and a familial history of suicide.•Mixed episodes and benzodiazepines are associated with history of suicide attempt in BD.•Insomnia, earlier onset of activity, woman gender and vigorous circadian type are independent predictors.•The predictive value of these biomarkers must be confirmed in a prospective study.