Crystal methamphetamine use among young adults in the United States is considerably higher than previous surveys indicate, according to new research funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health (NIH). The study, published in the July issue of the journal Addiction, found 2.8 percent of young adults (ages 18-26) reported use of crystal methamphetamine in the past year during 2001-2002. This is higher than the annual prevalence of crystal methamphetamine use by young adults (ages 19-28) of 1.4 percent reported by NIDA’s 2002 Monitoring the Future Survey.

Previous national surveys indicate that methamphetamine prevalence is highest among young adults, but until now, few scientific papers have looked at the characteristics and behaviors associated with its use in this age group. Using nationally representative data, and examining the age group most prone to methamphetamine use (ages 18-26), the study found that young adult users are disproportionately white and male and live in the West, and that Native Americans were 4.2 times as likely as whites to use crystal methamphetamine. Users also tend to have lower social economic status, use other substances, such as alcohol, marijuana, and cocaine, and the male users are more likely to have had incarcerated fathers.

“Measuring drug use is always a challenge,” said NIH Director Dr. Elias A. Zerhouni. “This new information gives us a clearer picture of use among young adults, but also raises new concerns. Even occasional use of crystal methamphetamine is associated with multiple health and social risks, including a negative impact on families as well as straining emergency departments and law enforcement resources.”

“The study showed not only greater use of crystal methamphetamine, it also suggests the drug is associated with risky and antisocial behaviors, including other illicit drug use,” said NIDA Director Dr. Nora D. Volkow. “By examining these connections, we hope to identify new avenues for treatment and prevention.”

The study authors based their findings on data from the National Longitudinal Study of Adolescent Health (Add Health), which asked respondents about their use of crystal methamphetamine in the past year and past 30 days. They examined certain characteristics of crystal methamphetamine users, such as their use of other substances, sociodemographics, and novelty-seeking behavior. They also looked at what was unique about crystal methamphetamine users compared to other drug users, and the associations between past year crystal methamphetamine use and antisocial or risk behaviors, such as crime/violence and risky sexual behavior. To maintain confidentiality, Add Health administered questionnaires via laptop computer using computer-assisted self-interviewing (CASI) technology.

The study found that use of crystal methamphetamine and associations with both criminal behavior and risky sex differed between men and women. Associations with both types of behaviors tended to be stronger among women than among men. Among women, the study found crystal methamphetamine use to be significantly associated with drug sales and risky sexual behavior, such as low condom use. However, the authors emphasize that more research is needed to determine whether women who sell drugs are more likely to use crystal methamphetamine or whether use of the drug leads to criminal drug sales among women.

Crystal methamphetamine (also referred to as “ice,” “crystal,” “glass,” and “tina”) is a common form of methamphetamine, a highly addictive stimulant that affects the central nervous system. As with the powdered form, users of crystal methamphetamine are drawn to its euphoric and stimulant effects, but the drug has higher purity and more potential for abuse. Typically smoked, it produces an immediate, intense sensation and has longer acting physiological effects than powder, which also amplifies its addiction potential and adverse health consequences. Those can include: mood disturbances, cardiovascular problems, heat stroke, convulsions, and psychotic symptoms that can sometimes last for months or years after methamphetamine abuse has ceased.

“This study presents a new perspective on crystal methamphetamine users in the United States,” said Dr. Denise D. Hallfors, of the Pacific Institute for Research and Evaluation and a co-author on the study. “We hope that this new information will aid in the development of appropriate interventions and help to inform public policy.”

To date, nationally representative survey research on crystal and other methamphetamine use has been based on two Federal sources: Monitoring the Future (MTF), and the National Survey on Drug Use and Health (NSDUH). In those surveys, annual prevalence of crystal methamphetamine use was 2.1 percent among 12th graders and 1.5 percent among young adults aged 19-28 (1.8 percent for men, 1.2 percent for women). The 2004 NSDUH survey did not ask specifically about crystal methamphetamine, but reported that past year methamphetamine use was highest among young adults (18-25), compared to youths and other adults.

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 to inform policy and improve practice. Fact sheets on the health effects of drugs of abuse and further information on NIDA research can be found on the NIDA web site at http://www.drugabuse.gov.

The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 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 it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.