Cyclothymic-depressive-anxious-irritable (CDAI) temperament has been linked to increased suicidal risk. Sleep disturbance and short self-reported sleep duration have been associated with suicidal ideation and behavior independently of a current major depressive episode (MDE).

This cross-sectional study in consecutive hospitalized suicide attempters aimed to investigate the interplay of temperament with proximal sleep disturbance in predicting suicide intent.

Depression severity was measured with Major Depression Inventory, whereby DSM-IV-TR diagnosis of current MDE was derived. Temporally proximal sleep disturbance (during ≥2 weeks preceding the attempt) was assessed with Athens Insomnia Scale (AIS); average night sleep duration (ANSD) was also self-reported. Suicidal intent was recorded with Beck's Suicide Intent Scale (BSIS). Attempters’ temperament profile was investigated with TEMPS-A self-report questionnaire. A two-step cluster analysis of TEMPS-A subscales mean scores was performed. BSIS was sequentially regressed on AIS and ANSD along with their interactions with temperament clusters after adjusting for clinicodemographic variables and current MDE.

114 subjects (57.9% females), aged 16-87 (44.1±17.7) years were included. 50% reported previous attempts. 38.6% were currently depressed. 62.3% suffered from insomnia (AIS score ≥6); 42.1% slept ≤5 hours per night on average. Cluster analysis identified a CDAI group and a non-CDAI one. In multiple regressions, BSIS was independently associated with current MDE, CDAI temperament profile, AIS (beta=0.43, p=0.004) and ANSD (beta=-0.40, p=0.002). Significant interactions of temperament cluster with AIS (p=0.017) and ANSD (p=0.011) were recorded.

Temperament profile interacts with proximal insomnia and short self-reported sleep duration in predicting suicidal intent in recent attempters.