A doctoral study sheds light on factors underlying suicidal thoughts and acts

A recent doctoral dissertation demonstrates that the risk of suicide of patients treated in hospital for depression has been halved in Finland. However, the data also reveals that factors related to education and income levels usually associated with wellbeing may even increase the suicide risk of depressed patients that have undergone hospital treatment.

In his recent doctoral dissertation, Kari Aaltonen, Licentiate of Medicine, investigated factors that account for suicidal thoughts, as well as suicide attempts and deaths among Finnish patients who were treated in psychiatric specialist care for depression or bipolar disorder.

In the first two articles of the dissertation, Aaltonen examined the differences in risk factors associated with suicidal thoughts and attempts. Altogether 188 patients in psychiatric specialist care in the Helsinki Metropolitan Area suffering from depression and 99 suffering from bipolar disorder took part in the study.

Of all study subjects, 34% reported seriously considering committing suicide at some point in their lives without actually making an attempt. In addition to severe depressive disorder and type II bipolar disorder, factors contributing to suicidal thinking included younger age, hopelessness and physical abuse experienced in childhood.

Of those participating in the study, 45% had attempted suicide at least once; reasons for such attempts included severe symptoms of depression, alcohol dependence, characteristics of borderline personality disorder and physical abuse experienced in childhood.

"The findings suggest that physical abuse during childhood may predispose individuals to borderline personality disorder traits, which, in turn, make them susceptible to suicide attempts," Aaltonen explains.

"As a rule, the factors underlying suicidal thoughts seem to be depression and hopelessness, whereas a more serious symptom picture or factors indicating reduced self control account for actual attempts."

A simultaneous increase in outpatient care and drug therapies for depression and reduction in the risk of suicide

The last two articles in Aaltonen's dissertation focused on suicidal risk caused by depression among patients treated in hospital for the first time for depression.

The treatment periods of the Finnish patients occurred between 1991 and 2011. Altogether 56,826 patients were included in the study. At its longest, their risk of suicide death was monitored for 24 years.

As far as is known, this is the most extensive and comprehensive follow-up study on the subject in the world.

Of all patients, 2,587 died of suicide (1,609 men and 978 women).

However, the risk of suicide for patients who received their first hospital inpatient treatment between 2006 and 2011 was half that of patients treated in 1991–1995.

"One of the main findings of the study was the halving of the suicide risk, even though patients today spend a shorter period in hospital while most likely suffering from a more serious disorder.

This is explained, in addition to the shortening of treatment periods, by a drop in treatment numbers. During the study period, outpatient care has been developed and the use of psychotropic medication has grown approximately eight-fold," Aaltonen summarises.

During the follow-up period, the risk of suicide was 8.6% for men and 4.1% for women.

The risk of suicide death was the highest in the first year after hospital care, dropping by half in the subsequent year. Those who had previously attempted suicide were at a particularly high risk: among men, the probability of suicide death was 15.4%, and 8.5% among women.

Male gender, an earlier suicide attempt, severe depressive disorder, alcohol dependence and living by oneself, among others, were predictive of suicide death. Relatively higher level of education and family income were the most surprising predictors.

"This is a result contrary to the usual findings concerning the population. There may be several reasons for this, such as losing control of one's life or a significant change in one's life after discharge, such as unemployment, a divorce or a serious physical illness," Aaltonen says.

Kari Aaltonen, Licentiate of Medicine, will defend his doctoral dissertation entitled "Suicidal behavior in depressive or bipolar disorders" at the Faculty of Medicine, University of Helsinki, on 1 February 2019 at 12.00. The public examination will take place at Auditorium Christian Sibelius, HUH Psychiatry Centre, Välskärinkatu 12.

The dissertation will be published in the publication series Dissertationes Scholae Doctoralis Ad Sanitatem Investigandam Universitatis Helsinkiensis. The dissertation is also available in electronic form through the E-thesis service.

Contact details:

Kari Aaltonen, psychiatrist, HUS Acute Psychiatry and Consultations division, kari.aaltonen@hus.fi