Suicide and mortality related to mental disorder in three Swedish cohorts

Aims: The subject of this thesis is suicide and other premature death related to mental disorder. The overall aim is to provide knowledge to improve prevention strategies. The specific aims are as follows: Study I: To identify predictors of suicide in a cohort with long-term mental disorder. Study II: To analyse mortality by mental health service and psychiatric diagnosis in a cohort with long-term mental disorder. Study III: To investigate the impact of psychiatric morbidity on suicide risk following a suicide attempt. Study IV: To examine familial suicide risks in a total population sample. Methods: Studies I and II. Adult residents with mental disorder in Stockholm County, Sweden, were identified in 1997. This register (n=12,247) was linked to national registers. Discharges from psychiatric inpatient care during 1990 2000 and deaths during 1997 2000 were identified. Predictors of suicide in the cohort were investigated; standardised mortality ratios were calculated. Study III. Data on all people living in Sweden 1973 82 were linked to national registers. People hospitalised during the period 1973 82 due to attempted suicide were identified. The cohort (n=39,685) consisted of those with a studied psychiatric diagnosis present at index attempt (cases) and those without a psychiatric diagnosis within a year after the suicide attempt (reference subjects). Patients were followed for 21 31 years. Survival curves for suicide were plotted and hazard ratios computed. Study IV. A population-based cohort (n=7,969,645) was created by linkage of Swedish national registers. Persons with death classified as definite or uncertain suicide 1952 2003 were identified (n=83,951). Odds ratios for suicide in relatives of suicide probands were calculated in relation to relatives of controls. Results: Study I. Predictors of suicide included previous suicide attempt, a history of psychiatric inpatient care, and unmet need of a contact person. Borderline personality disorder was the strong