Suicide and hospitalization for mental disorders in Sweden: a population-based case-control study

Abstract

The aim of this study was to estimate suicide risk during hospitalization and in the year following discharge for patients with mental disorders. All suicide cases in Sweden 18 years and older, between 1991 and 2003 (N=20,675; 70% male), were individually matched to 10 controls from the general Swedish population. Discharge diagnoses in the year before suicide of any mental disorder, mood disorder, schizophrenia spectrum disorder, and alcohol use disorder were identified from the Swedish Patient Register. Highest suicide risk during hospitalization and in the year following discharge was found for mood disorder [odds ratio (OR) 55 (95% CI, 47-65) for men and 86 (95% CI, 70-107) for women], with the risk peaking in the first week following discharge [OR 177 (95% CI, 78-401) for men and OR 268 (95% CI, 85-846) for women]. Compared to that for mood disorder, the suicide risk for schizophrenia spectrum disorder and alcohol use disorder was about half and more constant over time. The majority of suicide victims with a psychiatric diagnosis had been discharged from psychiatric treatment more than a month before the suicide. Over time, a constant proportion of 25% of the suicide victims had been hospitalized with a mental disorder in the year before suicide (23% of males and 31% of females), despite a significant decrease in psychiatric hospitalizations in the population. In conclusion, suicide risk was found to vary by type of mental disorder, time since discharge, and sex. This should be taken into account when planning suicide preventive efforts.