Methamphetamine study suggests increased risk for HIV transmission

WINSTON-SALEM, N.C. – New findings that one in 20 North Carolina men who have sex with men (MSM) reported using crystal methamphetamine during the previous month suggests increased risk for spreading HIV and other sexually transmitted diseases (STD), according to researchers from Wake Forest University School of Medicine and colleagues.

The rate of methamphetamine use among 1,189 MSM was 30 times higher than levels reported in the general U.S. population over the same period. Methampehtamine, or “meth,” is a highly addictive stimulant that has been found to impair judgment, decrease inhibition, increase impulsivity and enhance sexual sensitivity – which can all increase the potential for transmitting HIV.

The study’s authors found that participants who reported using methamphetamines were more likely to report inconsistent condom use during anal sex within the past three months, a history of STD infection, being HIV-positive and using medications designed to treat erectile dysfunction.

“Until now, there has been little data on meth use in the Southeast,” said lead author Scott D. Rhodes, Ph.D. M.P.H., associate professor in the Department of Social Sciences and Health Policy. “Our findings, including that meth users were more likely to be HIV-positive, suggest that prevention, intervention and treatment efforts are urgently needed.”

Rhodes noted that some of the men reported having sex with both men and women, which means the risk of HIV extends to both sexes.

The study’s results will be published on Aug. 20 in AIDS Patient Care and STDs, a leading AIDS journal that provides the latest research for clinicians and researchers. It is among the first to document meth use among MSM in the South, which carries a disproportionate HIV, AIDS, and STD burden, with 46 percent of newly identified cases.

“The findings underscore the need for further research and intervention,” said Rhodes. “The HIV/AIDS epidemic is clearly not over. We must develop innovative intervention approaches designed to reach communities at highest risk. Men who have sex with men, whether or not they identify themselves as gay, who use drugs like methamphetamines are clearly at higher risk. Yet currently nothing is being done in the Southeast.”

Participants were recruited in 2005 in five gay bars and in five geographically defined internet chat rooms in central North Carolina (primarily rural/suburban areas) and were asked to complete a brief assessment of drug use and other risk behaviors. Of the 1,189 MSM, two-thirds self-identified as black or other minorities, and 25 percent as bisexual. The mean age was 29 years.

In addition to being more inclined to risky sexual behaviors, the study participants who said they used methamphetamines were also more likely to report having higher education and health insurance coverage.

“Because users of methamphetamines were more likely to have higher educational levels and report having health insurance, we must change the way we think about meth users and develop sophisticated prevention strategies that are appropriate for these types of users,” noted Rhodes. “In addition, the link between meth use and the use of drugs for sexual dysfunction among a young population deserves attention. Meth use in combination with one of these medications may be having an even more profound impact on the HIV and STD disease epidemics in the South.”

Rhodes is also affiliated with the Maya Angelou Research Center on Minority Health at Wake Forest. In 2006, Rhodes won the New Investigator Award in Clinical Sciences at Wake Forest.

###
The study’s co-authors include Emily Knipper and Aimee M. Wilkin, M.D., M.P.H., both with Wake Forest, Kenneth C. Hergenrather, Ph.D., M.S.Ed., M.R.C., of George Washington University, Leland J. Yee, Ph.D., M.P.H., of the University of Pittsburgh, and Morrow R. Omli, M.A.Ed., of the University of Florida.

Media Contacts: Karen Richardson, krchrdsn@wfubmc.edu, or Shannon Koontz, shkoontz@wfubmc.edu, 336-716-4587.

Wake Forest University Baptist Medical Center is an academic health system comprised of North Carolina Baptist Hospital and Wake Forest University Health Sciences, which operates the university’s School of Medicine. U.S. News & World Report ranks Wake Forest University School of Medicine 18th in family medicine, 20th in geriatrics, 25th in primary care and 41st in research among the nation’s medical schools. It ranks 35th in research funding by the National Institutes of Health. Almost 150 members of the medical school faculty are listed in Best Doctors in America.

Contact: Karen Richardson
krchrdsn@wfubmc.edu
336-716-4453
Wake Forest University Baptist Medical Center

Global Health Vision

FMS Global News

Source

New treatment effective in counteracting cocaine-induced symptoms

DALLAS – Aug. 13, 2007 – UT Southwestern Medical Center researchers have discovered a treatment that counteracts the effects of cocaine on the human cardiovascular system, including lowering the elevated heart rate and blood pressure often found in cocaine users.

“We have found that cocaine’s effects on the cardiovascular system can be reversed by the use of a drug called dexmedetomidine, which is currently approved by the Food and Drug Administration for anesthetic purposes in operating rooms or intensive care units,” said Dr. Wanpen Vongpatanasin, associate professor of internal medicine and senior author of a study appearing in the Aug. 14 issue of the Journal of the American College of Cardiology.

Researchers used dexmedetomidine to test whether cocaine’s effect on the cardiovascular system could be muted. They found that the drug was effective in reversing the actions of cocaine on heart rate, blood pressure and vascular resistance in the skin by interfering with the ability of cocaine to increase nerve activity.

“Typically, patients with cocaine overdoses in the emergency room are treated with nitroglycerin, sedatives such as Valium, and some blood-pressure medications such as calcium channel blockers and some beta blockers,” Dr. Vongpatanasin said. “However, the standard treatments don’t alleviate all of the adverse effects of cocaine on the heart, blood pressure and central nervous system.”

The study examined results from 22 healthy adults who reported to have never used cocaine. The investigators administered a small, medically approved dose of cocaine nose drops to the study participants, which doubled their sympathetic nerve activity, part of the body’s “automatic” response system that becomes more active during times of stress. Participants experienced increases in several cardiovascular parameters including heart rate, blood pressure and resistance to blood flow in the skin.

Microelectrodes, similar to acupuncture needles, were used to record sympathetic nerve activity following doses of intranasal cocaine.

Research subjects who were treated with dexmedetomidine had a decrease in sympathetic nerve activity as well as in all three cardiovascular parameters, which returned to baseline levels measured before administration of cocaine. Dexmedetomidine proved to be more effective than intravenous saline, which was used as a placebo in another group of study participants.

Cocaine abuse in the U.S. is widespread, with nearly 35 million Americans reporting having ever tried cocaine and an estimated 7.3 million users, including 15 percent of young adults ages 18 to 25, according to the National Institute on Drug Abuse. Life-threatening emergencies related to cocaine use include sudden cardiac death, high blood pressure, stroke and acute myocardial infarctions.

“We also found that dexmedetomidine was equally effective in counteracting effects of cocaine in subjects with a rare genetic mutation thought to disrupt the effects of dexmedetomidine,” said Dr. Ronald Victor, professor of internal medicine and co-author of the study. “Because this particular mutation is more common in African-Americans than in Caucasians, our study results are applicable to a more diverse, multiethnic population.” Further research is needed, study authors said, to determine whether the treatment would be effective for acute cocaine overdose in the emergency room and to gauge whether it would be effective in reversing cocaine-induced constriction of the coronary vessels to the same degree it does in skin vessels.

###

Other UT Southwestern authors include Dr. Zhongyun Wang, research associate in internal medicine; Debbie Arbique, senior registered nurse; Dr. David Leonard, assistant professor of clinical sciences and internal medicine; and Dr. Jia-Ling Li, senior research scientist in internal medicine.

Funding was provided by the National Institute on Drug Abuse, the Donald W. Reynolds Foundation and the Texas chapter of the American Society of Hypertension.

This news release is available on our World Wide Web home page at:

http://www.utsouthwestern.edu/home/news/index.html

To automatically receive news releases from UT Southwestern via e-mail, subscribe at: http://www.utsouthwestern.edu/receivenews

Contact: Katherine Morales
katherine.morales@utsouthwestern.edu
214-638-3404
UT Southwestern Medical Center

Global Health Vision

FMS Global News

Source