Passing along.

"NIH OLIB (NIH/OD)" <olib@...> wrote:

Date: Thu, 11 Aug 2005 15:13:52 -0400
From: "NIH OLIB (NIH/OD)" <olib@...>
Subject: METHAMPHETAMINE ABUSE, HIV INFECTION CAUSE CHANGES IN BRAIN STRUC TURE
To: NIHPRESS@...

U.S. Department of Health and Human Services
NATIONAL INSTITUTES OF HEALTH
NIH News
National Institute on Drug Abuse (NIDA)
http://www.nida.nih.gov/

FOR IMMEDIATE RELEASE: Thursday, August 11, 2005

CONTACT: Blair Gately, 301-443-6245
Contacto en Español: Sara Wilson, 301-594-6145

METHAMPHETAMINE ABUSE, HIV INFECTION CAUSE CHANGES IN BRAIN STRUCTURE
Alterations May Be Related to Cognitive Deficits

New research published in the August 2005 issue of the "American Journal of
Psychiatry" indicates that methamphetamine abuse and HIV infection cause
significant alterations in the size of certain brain structures, and in both
cases the changes may be associated with impaired cognitive functions, such
as difficulties in learning new information, solving problems, maintaining
attention and quickly processing information. Co-occurring methamphetamine
abuse and HIV infection appears to result in greater impairment than each
condition alone.

"Methamphetamine abuse is linked with HIV, hepatitis C, and other sexually
transmitted diseases, not only by the use of contaminated injection
equipment, but also due to increased risky sexual behaviors," says Dr. Nora
D. Volkow, director of the National Institute on Drug Abuse (NIDA), National
Institutes of Health, which helped support the research. "These findings
show that methamphetamine abuse and HIV infection each cause significant
changes in the volume of brain gray matter structures and cognitive
function."

Scientists led by Dr. Terry Jernigan of the HIV Neurobehavioral Research
Center of the University of California-San Diego conducted brain scans to
analyze structural volume changes in 103 adults divided among four
populations: methamphetamine abusers who were HIV-positive; methamphetamine
abusers who were HIV-negative; nonabusers who were HIV-positive; and
nonabusers who were HIV-negative. They also assessed the ability to think
and reason using a detailed battery of tests that examined speed of
information processing, attention/working memory, learning and delayed
recall, abstraction/executive functioning, verbal fluency, and motor
functioning.

They observed that methamphetamine abuse is associated with increases in the
volume of the brain's parietal cortex (which helps people to understand and
pay attention to what's going on around them) and basal ganglia (linked to
motor function and motivation). HIV infection is associated with prominent
volume losses in the cerebral cortex (involved in higher thought, reasoning,
and memory), basal ganglia, and hippocampus (involved in memory and
learning).

The scientists stress that among the recent methamphetamine abusers in the
study, the degree of volume increase in the parietal cortex was associated
with worse cognitive function.

"In HIV-infected people, the cognitive impairments are associated with
decreased employment and vocational abilities, difficulties with medication
management, impaired driving performance, and problems with general
activities of daily living, such as managing money," says Dr. Jernigan. "The
impact of methamphetamine on daily functioning is less well studied,
although it is known that abusers of the drug have impaired decision-making
abilities. These could potentially affect treatment and relapse prevention
efforts, as well as things like money management and driving performance."

The brain volume changes associated with methamphetamine abuse did not
correlate with the amount of the drug a person ingested. However, the study
results suggest that younger methamphetamine abusers showed larger effects
in some brain regions. Among HIV-infected individuals, the researchers noted
a direct association between the severity of the infection and greater loss
of brain matter.

In methamphetamine abusers who are also HIV-positive, decreased volumes are
correlated with increased cognitive impairment in one brain region, the
hippocampus.

Dr. Jernigan explains that the changes seen in brain structures could be the
result of inflammation in the brain and/or compensatory changes associated
with methamphetamine toxicity. Also, brain inflammation associated with HIV
infection may contribute to brain cell shrinkage or loss.

Dr. Volkow says medications that reduce inflammation might be useful in
treating methamphetamine abusers.

"The effects of methamphetamine and HIV on the brain are distinct but may
affect the same brain regions, so understanding how the underlying
mechanisms interact also may lead to more effective therapies and the
information should be useful in guiding future studies," Dr. Volkow
concludes.

The National Institute on Drug Abuse is a component of the National
Institutes of Health, U.S. Department of Health and Human Services. NIDA
supports most of the world's research on the health aspects of drug abuse
and addiction. The Institute carries out a large variety of programs to
ensure the rapid dissemination of research information and its
implementation in policy and practice. Fact sheets on the health effects of
drugs of abuse and information on NIDA research and other activities can be
found on the NIDA home page at http://www.drugabuse.gov/.

The National Institutes of Health (NIH) -- "The Nation's Medical Research
Agency" -- is comprised of 27 Institutes and Centers and is a component of
the U. S. Department of Health and Human Services. It is the primary Federal
agency for conducting and supporting basic, clinical, and translational
medical research, and investigates the causes, treatments, and cures for
both common and rare diseases. For more information about NIH and its
programs, visit http://www.nih.gov.

##

This NIH News Release is available online at:
http://www.nih.gov/news/pr/aug2005/nida-11.htm.

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