December 23, 2005

Impulsivity, alcohol linked to suicide

By Karla Gale

NEW YORK (Reuters Health) - Men with severe depression are
more likely to commit suicide if they abuse alcohol and have
"cluster B" personality disorder, which relates to impulsive
and/or aggressive behavior, new study findings suggest.

"Why some patients with major depressive disorder die by
suicide while others with seemingly the same disorder do not,
is a question of enormous clinical relevance," Dr. Gustavo
Turecki and colleagues write in the American Journal of

The researchers compared psychiatric factors among men with
major depressive disorder, 104 of whom committed suicide and 74
who are alive. Psychiatric disorders were determined using
proxy-based interviews of relatives, friends or significant
others. The two groups were similar in terms of age, marital
and parental status, education level, race and religion.

Personality disorders characterized by the presence of
impulsive or aggressive personality traits -- borderline and
antisocial -- were associated with a 17-fold greater likelihood
of committing suicide. With alcohol abuse or dependence for the
last 6 months, the risk increased 4-fold.

These observations "support the vision that higher levels
of impulsive and aggressive behaviors combined with behavioral
disinhibition facilitated by substance use may mediate suicide
in major depressive disorder," the team concludes.

"When we looked at the effects of age, those risk factors
were particularly more important among younger cases," Turecki
told Reuters Health.

"So if a clinician has a patient that has major depression
and comorbidity with substance-related problems and the
presence of cluster B personality trait and is younger, these
are patients you want to make sure you pay close attention to,"
he added.

"Further studies should be carried out to investigate the
external validity of these findings, particularly among women
and in other diagnostic categories associated with suicide such
as schizophrenia," Turecki concluded.

SOURCE: American Journal of Psychiatry, November 2005.