The impact of comorbid cannabis and methamphetamine use on mental health among regular ecstasy users
Scott, LA and Roxburgh, A and Bruno, R and Matthews, A and Burns, L, The impact of comorbid cannabis and methamphetamine use on mental health among regular ecstasy users, Addictive Behaviors, 37, (9) pp. 1058-1062. ISSN 0306-4603 (2012) [Refereed Article]
Objective: Residual effects of ecstasy use induce neurotransmitter changes that make it biologically plausible
that extended use of the drug may induce psychological distress. However, there has been only mixed support
for this in the literature. The presence of polysubstance use is a confounding factor. The aim of this
study was to investigate whether regular cannabis and/or regular methamphetamine use confers additional
risk of poor mental health and high levels of psychological distress, beyond regular ecstasy use alone.
Method: Three years of data from a yearly, cross-sectional, quantitative survey of Australian regular ecstasy
users was examined. Participants were divided into four groups according to whether they regularly (at
least monthly) used ecstasy only (n=936), ecstasy and weekly cannabis (n=697), ecstasy and weekly
methamphetamine (n=108) or ecstasy, weekly cannabis and weekly methamphetamine (n=180). Self-reported
mental health problems and Kessler Psychological Distress Scale (K10) were examined.
Results: Approximately one-fifth of participants self-reported at least one mental health problem, most commonly
depression and anxiety. The addition of regular cannabis and/or methamphetamine use substantially
increases the likelihood of self-reported mental health problems, particularly with regard to paranoia, over
regular ecstasy use alone. Regular cannabis use remained significantly associated with self reported mental
health problems even when other differences between groups were accounted for. Regular cannabis and
methamphetamine use was also associated with earlier initiation to ecstasy use.
Conclusions: These findings suggest that patterns of drug use can help identify at risk groups that could benefit
from targeted approaches in education and interventions. Given that early initiation to substance use was more
common in those with regular cannabis and methamphetamine use and given that this group had a higher likelihood
of mental health problems, work around delaying onset of initiation should continue to be a priority.
ecstasy, cannabis, methamphetamine, MDMA, psychological distress, K10, mental health disorders