0656 Demographic and Clinical Features of Nocturnal Suicide

Abstract Introduction The risk for suicide is greatest at night after adjusting population wakefulness, possibly due to sleep- and circadian-dependent changes in neurophysiology promote sleep. Those who die by night, however, may differ demographic and/or clinical characteristics from those during the day. Methods An archival analysis of National Violent Death Reporting System 2003-2017 identified 77,784 deaths with time fatal injury. Cases were divided into daytime (5AM 10:59PM) or nighttime (11PM 4:59AM) characterized age, sex, race, ethnicity, marital status, military service, education, prior diagnosis an anxiety disorder, bipolar depression, history suicidal ideation, PTSD, schizophrenia, as well presence opiate cannabis, blood alcohol level (BAL) on autopsy. Bidirectional stepwise regression robust Poisson models significant predictors nocturnal using incident ratios (IRR). Results Nocturnal suicides differed all sociodemographic variables. more prevalent among elevated BAL, tested positive cannabis. Stepwise a age BAL interaction. Using adults 35-64 BAL=0mg/dl reference, BAL<80mg/dl had 46% greater BAL≥80mg/dl 78% risk. Individuals 15-34 that was 26% BAL=0mg/dl, 84% BAL<80mg/dl, 298% BAL≥80mg/dl. Conversely, individuals 65 older 27% less likely while BAL>0mg/dl did not aged BAL=0mg/dl. also 17% 13% documented depression. Conclusion intoxicated younger previous ideation. However, victims depression night. Further research needed target prevention efforts appropriately times mood, substance, use disorders. Support (If Any)