LONGITUDINAL ASSOCIATIONS BETWEEN METHAMPHETAMINE USE AND DEPRESSION AMONG YOUNG ADULTS IN THE UNITED STATES: A SECONDARY ANALYSIS

Abstract

Methamphetamine is a powerful, highly addictive central nervous system stimulant that is associated with deleterious health outcomes. In particular, there is evidence from clinical treatment samples and criminal justice populations that methamphetamine use is associated with depression, however this association has yet to be investigated in a nationally representative sample. Given that young adults are the group most prone to methamphetamine use, this study used a total of 8,688 respondents from Waves III (2001-02; ages 18-28) and IV (2007-08; ages 24-34) of the National Study of Adolescent Health (Add Health) to examine whether methamphetamine use (past year use at Wave III) was associated with depression, as measured by the Center for Epidemiologic Studies Depression Scale (CES-D). This study also evaluated whether gender, functional poverty status, polydrug use, and childhood maltreatment moderated the association between methamphetamine use and depression.

Logistic regressions were used to determine the odds ratios (OR) and 95% confidence intervals (95% CI) in unadjusted and adjusted analyses (controlling for gender, age, race/ethnicity, US region, functional poverty status, childhood maltreatment, polydrug use, and depression at Wave III). Results indicated that in the general population, methamphetamine users have increased odds of becoming depressed (OR: 2.13, 95% CI: 1.38-3.27) and controlling for covariates, including Wave III depression, methamphetamine use independently predicted later depression (OR: 1.81, 95% CI: 1.12-2.92). None of the potential moderator variables tested had an effect on the association. These findings indicate that longitudinally, methamphetamine users are at an increased risk for depression, regardless of other factors and perhaps drug prevention and treatment programs for methamphetamine use should focus more on decreasing depression in this population. This study provides a broader understanding of the relationship between methamphetamine use and depression in a nationally representative sample, though further investigation into potential mediators and moderators is warranted.