People with a history of winter seasonal affective disorder (SAD) may lower
their risk of having a recurrence by taking the antidepressant bupropion XL
early in the autumn before symptoms emerge.
This finding comes from three similarly designed prospective double-blind,
placebo-controlled studies involving 1,042 patients at 151 sites in the U.S.
and Canada.
A team of eight researchers headed by Jack Modell, M.D., vice president for
clinical psychiatry-North America at GlaxoSmithKline, the medication's
manufacturer, conducted the three trials (referred to as A, B, and C).
According to their report in the October 15, 2005, Biological
Psychiatry, the researchers enrolled adult volunteers with a history of
SAD between September and November 2002 for studies A and B, and between
September and November 2003 for study C. All subjects were diagnosed with SAD
by psychiatrists after a clinical interview.
Enrollees started by taking bupropion XL 150 mg or placebo orally every
morning for a week. They then took 300 mg of the drug or a matching placebo
orally every morning unless the investigator thought they could not tolerate
the higher dose. If they later were unable to tolerate 300 mg a day, their
dose was reduced to 150 mg a day (or matching placebo) for the rest of the
study. Some 80 percent of all subjects used the dose of 300 mg a day or the
matching placebo for most of the study.
Beginning in the first week of spring, investigators lowered the subjects'
dose of bupropion XL (or matching placebo) from 300 mg a day to 150 mg a day
for two weeks, and then discontinued it. Investigators evaluated participants
in person throughout the study and via telephone for eight weeks
afterward.
Among all participants, 84 (16 percent) developed a recurrence of major
depression on bupropion XL, compared with 142 (28 percent) of those on
placebo.
Given the high recurrence rates subjects had reported on
enrollment—13 previous episodes on average—the relatively small
proportion of subjects in the placebo group who experienced a SAD episode was
somewhat surprising, the researchers noted. Involvement in a clinical trial
with close personal attention, they theorized, may offer protection against
depression.
While light therapy has been a mainstay of SAD treatment for the past two
decades, some patients may find it cumbersome and inconvenient. The three
studies described in this paper, the authors said, "are the first to
show that an antidepressant administered before the onset of a recurrent major
depressive episode can have a preventative effect."
"A larger issue," Modell told Psychiatric News,"
is that even among psychiatrists, seasonal patterns of depression often
go unrecognized and untreated."
"Seasonal Affective Disorder and Its Prevention by Anticipatory
Treatment With Bupropion XL" can be accessed at<www.sciencedirect.com>
by clicking on "Journals," "B," "Biological
Psychiatry," and "Volume 58, Issue 8."