He cited a major study conducted in Finland which found that only
6 percent of all suicides related to a depressive illness were
receiving adequate doses of antidepressant treatment prior to
death.
"And almost half were in treatment," Mann said.
"So only a small minority were receiving adequate treatment.
We have a long way to go in addressing this lack."
Mann presented a model of suicidal behavior in which there are
three categories of triggers: acute psychiatric illness; substance,
alcohol or medication abuse; and social or family crisis.
"These triggers appear to be necessary for suicide to take
place-and determine timing-but in and of themselves they are not
significant factors," he said. "In other words, there's
something else involved than just the trigger, and that's the
threshold. It's the interaction of the threshold with trigger
that determines risk."
Mann said factors governing the threshold for suicidal behavior
include genetics, personality, alcohol, family and social support,
chronic illnesses and serotonin levels.
For instance, 95 percent of those who commit suicide have psychiatric
illness. There is evidence for a lower threshold for suicidal
acts in a subgroup with major depression. Severity of depression
is a poor predictor of suicide risk.
"Yet this is the one factor clinicians rely on," Mann
said, adding that his group looked at the timing of suicide following
the onset of major depressive disorder and found that after three
years, the slope flattens out. "So most suicide attempts
occurred relatively early in the course of illness."
Therefore, finding more specific ways to predict suicidal behavior
is important, he stressed.
Serotonin Deficiency
