Antidepressant drug treatment is associated with a reduced risk of completed suicides and overall mortality among adults, although it also appears to increase the likelihood of nonfatal suicide attempts, according to a research team in Finland.

Despite the numerous studies that have addressed the effects of antidepressant drug use, the question of how antidepressants affect the risk of suicide remains open, Dr. Jari Tiihonen and colleagues note in the Archives of General Psychiatry.

Therefore, Tiihonen, a forensic psychiatrist at the University of Kuopio, and his group evaluated the risk between antidepressant use and mortality, based on an analysis of several Finnish databases.

The study group included 15,390 patients who were not psychotic, at least 10 years old, and hospitalized after a failed suicide attempt between 1997 and 2003. The authors evaluated treatment with three classes of antidepressant drugs: tricyclic antidepressants (such as Elavil); selective serotonin reuptake inhibitors (such as Prozac); and serotonergic-noradrenergic antidepressants (such as Effexor). During the follow-up period there were 602 completed suicides, 7,136 suicide attempts and 1,583 deaths.

The investigators’ initial analysis showed that “the number of previous suicide attempts was the strongest predictor of another suicide attempt, and age was the strongest predictor of death and suicide.”

After adjusting the data for the effect of other risk factors, the risk of completed suicide was lower in patients who were on an antidepressant compared with patients who were not on an antidepressant. There were no apparent differences by class of antidepressant used.

In contrast, the risk of a suicide attempt requiring hospitalization was greater in patients between 10 and 19 years old. The risk of an attempted, but not completed, suicide was increased further when selective serotonin reuptake inhibitors were used.

Patients on antidepressants less often attempted suicide using violent means, such as hanging or shooting.

In a secondary analysis, which examined cause of death other than suicide, the mortality risk from cardiovascular disease was significantly lower among antidepressant users versus non-users. This effect was greatest among patients taking selective serotonin reuptake inhibitors, particularly fluoxetine (Prozac).

Tiihonen and his associates conclude: “Antidepressant treatment may contribute to a substantial decrease in mortality among this patient population.”

SOURCE: Archives of General Psychiatry, December 2006.