The use of crystal methamphetamine by street-involved youth is linked to an increased risk of injecting drugs, with crystal methamphetamine being the drug most commonly used at the time of first injection, found a study published in CMAJ (Canadian Medical Association Journal).

Amphetamine-type drugs, including crystal methamphetamine, are second only to cannabis in popularity. Injection rates of crystal methamphetamine have increased substantially among adult drug users in some Canadian centres such as Vancouver, BC. Overall use of crystal methamphetamine by street-involved youth aged 15-24 in Canada also increased,from 2.5% in 1999 to 9.5% in 2005.

To understand whether crystal methamphetamine use is linked to first-time drug injection in youth, researchers from the BC Centre for Excellence in HIV/AIDS, University of British Columbia and the British Columbia Centre for Disease Control, Vancouver, looked at data from the At-Risk Youth Study of street-involved youth aged 14-26 in Vancouver. There were 991 youth who completed a questionnaire on drug use, with 395 (40%) reporting using crystal methamphetamine and 390 (39%) injecting drugs at the start of the study. The researchers focused on the 395 youth who had not injected drugs at the start of the study. They found that 64 (16%) of these young people reported injecting drugs for the first time during the study period (October 2005 to December 2010). The average age for first-time use of crystal methamphetamine was 14 years in youth who later became intravenous drug users.

"Within a sample of street-involved youth in a Canadian setting, recent noninjection use of crystal methamphetamine was independently associated with an increased risk of subsequent initiation of injection drug use," write Dr. Evan Wood and Dan Werb, BC Centre for Excellence in HIV/AIDS, with coauthors. "Within a subsample of first-time injection drug users, crystal methamphetamine was most commonly reported as the drug used during initiation events."

Although youth described varied locations for first-time drug injection, 39% reported injecting drugs in public places, many in Vancouver's downtown eastside neighbourhood. Participants reported injecting for the first time with other people present, including friends (57%), family members (13%) and acquaintances (10%).

"Addressing the impact of crystal methamphetamine use in increasing the risk of injection initiation among injection-naive street-involved youth represents an urgent public health priority," write the authors.

They call for further research to develop evidence-based interventions to prevent drug injection that consider the complexities of using crystal methamphetamine with other drugs.