Acute stress reaction and completed suicide.

BACKGROUND Acute stress reaction is a diagnosis given immediately following the experience of an exceptional mental or physical stressor. To the best of our knowledge, no study has examined the association between acute stress reaction diagnosis and suicide. The current study examined this association in a population-based sample. In addition, we examined comorbid psychiatric diagnoses as modifiers of this association. METHODS Data for the current study were obtained from the nationwide Danish health and administrative registries, which include data for all 5.4 million residents of Denmark. All suicides between 1 January 1994 and 31 December 2006 were included and controls were selected from a sample of all Danish residents. Using this nested case-control design, we examined 9612 suicide cases and 199 306 controls matched to cases with respect to gender, date of birth and time. RESULTS In total, 95 cases (0.99%) and 165 controls (0.08%) had a diagnosis of acute stress reaction. Those diagnosed with acute stress reaction had 10 times the rate of completed suicide compared with those without this diagnosis, adjusting for the control to case matching, depression and marital status (95% confidence interval 7.7-14). Additionally, persons with acute stress reaction and depression, or acute stress reaction and substance abuse, had a greater rate of suicide than expected based on their independent effects. CONCLUSIONS Acute stress reaction is a risk factor for completed suicide.