Attempts to link suicide or suicidality to prescribing trends for
antidepressants did not get much help from two observational studies in the
February 14 British Medical Journal (BMJ).
One found that antidepressant prescriptions in Britain doubled between 1999
and 2003, but then fell to the 1999 level between 2004 and 2005, possibly
because Britain's Medicines and Healthcare Products Regulatory Agency issued a
warning in December 2003 that use of SSRIs in young people was"
unfavourable."
Despite some short-term variability, the long-range trend from 1993 to 2005
indicated that suicide among 12- to 17-year-olds dropped annually by 3 percent
to 4 percent.
"These large changes in prescribing did not seem to be associated
with temporal trends in suicide or self-harm," wrote Benedict Wheeler,
Ph.D., a research fellow in the Department of Social Medicine at the
university of Bristol, and four colleagues in the BMJ study.
A second paper from the same department noted that suicide rates in England
and Wales for people aged 15 to 34 had declined since the 1990s and reached
their lowest levels in 30 years in 2005. David Gunnell, M.B., Ph.D., a
professor of epidemiology at Bristol, and colleagues speculated that the
introduction of catalytic converters in cars also is responsible for the drop
in the number of suicides since inhaled car exhaust in cars so equipped is
less lethal.
Changes in risk factors for suicide—divorce, unemployment, and
alcohol use—did not correlate significantly with changes in suicide
rates. Neither did rates of antidepressant prescribing, they said.
None of this surprises at least one observer. The two British studies,
showing a lack of connection between antidepressant prescribing rates and
rates of suicide among young people, are more likely to be true than earlier
studies linking use of antidepressants with reduced risk of suicide, wrote
Greg Simon, M.D., M.P.H., senior investigator at the Group Health Center for
Health Studies in Seattle, in an accompanying editorial.
"In truth, it would be surprising if antidepressants had any
effect—positive or negative—on the risk of suicide in the general
population," said Simon. Only half of adults and one-fourth of
adolescents diagnosed with major depression start on antidepressants, and many
of them stop within weeks. "Sustained use of antidepressants is probably
too rare to have much overall effect on risk of suicide in people living with
depression."
Regulatory warnings may have led to a reduction in antidepressant
prescribing, but they haven't done much for the other half of the regulators'
statement: closely monitoring patients as they start on the drugs.
"Only a fifth of patients [in the U.S.] starting [antidepressants]
have even three follow-ups visits over three months," Simon wrote."
Furthermore, follow-up rates have shown no improvement over the past
five years."
Reporting on an overall drop in antidepressant prescriptions fails to
distinguish just who is doing the prescribing, said one expert on suicide.
Herbert Hendin, M.D., president and medical director of Suicide Prevention
International in new york, said that much of the increase and drop-off in
antidepressant prescriptions came from general physicians. Antidepressant use
by psychiatrists for treating more seriously suicidal patients preceded their
use by general physicians, Hendin believes.
In an interview with Psychiatric News, he ascribed the run-up in
antidepressant prescribing to primary care physicians who were not treating
the most depressed patients. "It became like an aspirin," he
said.
That feeling changed with the FDA warnings, beginning early in 2004.
Primary care doctors no longer had the time or the expertise to closely follow
patients starting on antidepressants, so they simply cut back on prescribing
them.
"GPs might see patients once a month, but psychiatrists see their
patients more frequently and can see side effects pretty soon if they crop
up."
Psychiatrists also know more about these drugs and how they work and
probably haven't cut back on their use, he said. "I don't know of any
psychiatrist who is not prescribing them when needed."
Simon agreed that follow-up is the key to the proper use of SSRIs, even if
it hasn't appeared in the statistics. "We can only hope that regulatory
warnings will eventually have as much an effect on the quality of treatment as
on the quantity," he concluded.