Trauma
memories increase drug cravings
UB research findings highlight importance of treating
PTSD, abuse concurrently
By LOIS
BAKER
Contributing Editor
Post-traumatic
stress disorder (PTSD) increases craving in drug abusers diagnosed with
both conditions, confirming the need to treat the conditions simultaneously,
the first laboratory study of the two disorders has shown.
Research
drawing that conclusion, led by Scott F. Coffey, assistant professor
of psychiatry in the School of Medicine and Biomedical Sciences, appears
in the current issue of Drug and Alcohol Dependence.
"We know
from experience that drug abusers with PTSD do poorly in treatment,"
Coffey said, "but many providers of substance-abuse treatment are reluctant
to treat PTSD because it's such an emotionally charged condition. Common
practice is to treat the drug abuse and then the PTSD.
"But if
the PTSD symptoms are in part driving the substance abuse, asking a
patient to get off drugs before treating the PTSD is kind of unfair,"
he said. "We don't do that with drug abusers with depression or schizophrenia;
we treat the two disorders concurrently. Hopefully, this study will
encourage treatment providers to address drug abuse and PTSD at the
same time."
It's estimated
that as many as 40 percent of substance abusers suffer from PTSD, he
said.
Coffey,
a specialist in drug abuse and PTSD, conducted the research with colleagues
at the Medical University of South Carolina. The investigators used
a laboratory-based approach called "cue reactivity," in which subjects
are exposed to stimuli designed to remind them of a particular event
or situation in order to monitor their responses.
The study
involved 30 cocaine-dependent and 45 alcohol-dependent participants,
all of whom also suffered from PTSD resulting from a physical or sexual
attack. All participants were in treatment for their substance dependence,
and were drug-free at the time of the study, but reported using their
drug of choice within the past 60 days.
During
the initial interview, researchers asked participants to describe their
worst trauma in full detail. With the participants' permission, this
information was used in an audiotaped narrative that would serve as
the trauma-imagery cue during the laboratory session.
Each participant
also rated five standard neutral audio narratives for pleasantness and
emotional arousal. The script that participants rated closest to neutral
was used as their neutral imagery cue.
In addition,
interviewers discussed participants' drug of choice, and used the information
to develop individualized drug cues: for the cocaine abusers, a crack
pipe and bag of simulated crack cocaine; for the alcohol abusers, a
glass of the preferred alcoholic beverage, along with the bottle itself.
Wood chips served as the neutral "drug" cue for all participants.
Each laboratory
session began with a urine drug screen and questionnaire on which participants
reported their current level of craving. Retiring to a sound-proof booth,
subjects underwent four presentations of imagery and drug cues: trauma
imagery followed by a drug cue, neutral imagery followed by a drug cue,
trauma imagery followed by a neutral cue and neutral imagery followed
by a neutral cue.
Participants
listened to the imagery recordings through earphones with eyes closed
and were asked to continue to imagine the scene and experience the emotions
as vividly as possible. When a buzzer signaled them to open their eyes,
they were confronted by a drug or neutral cue.
Participants
rated their craving and other responses on a computerized questionnaire
immediately following each imagery-drug presentation.
Results
showed, not unexpectedly, that craving increased significantly when
participants were presented with trauma imagery and when participants
were presented with cues related to their substance of choice.
"From our
research with trauma victims, we know that intrusive trauma memories
are very upsetting to patients, and now we have shown that these trauma
memory-induced negative emotions increase craving in substance abusers
with PTSD," Coffey said. "These findings add support to our contention
that we need to treat the two disorders at the same time."
This first
investigation involving parallel experiments with cocaine and alcohol
abusers also turned up unexpected findings, he said. "We predicted that
cocaine abusers would have significantly higher craving than alcohol
abusers, based on our knowledge of cocaine's effects. But we found that
people with alcohol dependence reported much higher craving than cocaine
abusers when thinking about their trauma."
Coffey
said this finding makes sense in hindsight. "PTSD is an anxiety disorder.
It makes people become aroused, so they are much more likely to need
an anxiety-reducing drug, like alcohol, than a stimulant, like cocaine,
which would increase the arousal."