Suicidal behavior in depressive or bipolar disorders

A part of this thesis examined within the Helsinki University Psychiatric Consortium (HUPC) study explanatory factors for lifetime suicidal ideation or suicide attempts among patients with depressive or bipolar disorder in psychiatric care. Another part is a national register-based study investigating risk for suicide, its time trends and risk factors among first-hospitalized patients for depression. HUPC study is based on a random secondary-care sample of 287 patients with either depressive or bipolar disorder in the Helsinki metropolitan area. Lifetime principal clinical diagnoses were used. Patients were surveyed on multiple putative risk factors from multiple domains. Information on lifetime suicidal behavior was based on survey and patient record data. Of the HUPC cohort, 34% reported lifetime suicidal ideation and 45% had attempted suicide. Strongest explanatory factors for suicidal ideation without attempts were younger age, severe depressive disorder, type II bipolar disorder, and hopelessness. Strongest explanatory factors for suicide attempts were younger age, female sex, and severe depressive disorder with and without psychotic symptoms, type II bipolar disorder, alcohol dependence, and borderline personality disorder traits. In addition, childhood physical abuse independently explained lifetime suicidal ideation and suicide attempts. Borderline personality disorder traits mediated all of the total effect of childhood maltreatment on suicide attempts. A national cohort of 56 826 first-hospitalized patients for depression in 1991-2011 was followed on the registers up to the end of the year 2014 (maximum 24 years). The study linked individual level data from national registers. During the follow-up 2587 patients died by suicide. The cumulative risk for suicide was 8.6% in men and 4.1% in women. The risk for suicide was less than half among patients first hospitalized in 2006-2011 relative to patients first hospitalized in 1991-1995. The incidence rate was highest during the first year after discharge (2305 per 100 000 person-years in men, 973 per 100 000 person-years in women). Strongest predictors for suicide were male sex and previous suicide attempts. Among patients with previous suicide attempts, the cumulative probability for suicide was 15.4% in men and 8.5% in women. Other predictors were severe depression, psychotic depression, alcohol dependence, living alone, and higher socioeconomic status. Some gender differences in risk factors were found. Men died markedly more often than women by potentially more lethal methods. To conclude, risk factors for suicidal ideation and suicide attempts overlap, and may differ both qualitatively and quantitatively. Suicidal ideation is explained by depressive morbidity, hopelessness, and childhood physical abuse. Suicide attempters are characterized by more severe clinical characteristics and factors related to a predisposition to act on one’s thoughts. Borderline personality disorder traits may act as a major mediating factor between childhood maltreatment and suicide attempts. The cumulative risk of suicide in depression varies with time and contextual changes. The risk for suicide has declined substantially among former inpatients in Finland from 1991 to 2014. The first year after discharge forms a high-risk period. Clinical and sociodemographic characteristics predict long-term risk of suicide. Previous suicide attempters are at high-risk. Gender differences in risk factors are modest. The choice of potentially more lethal methods by men may explain men’s excess risk.