Predictors of methamphetamine use in a longitudinal birth cohort

Identifying predictors of methamphetamine use can inform population prevention strategies.

Participants (n = 1265) born in Christchurch, New Zealand were followed from birth to age 40. Methamphetamine outcomes (any use since the last interview, and regular use, defined as any period of at least weekly use) were ascertained by self-report at six interviews from age 18 to 40. Predictors with plausible associations with methamphetamine use were extracted from the study database. These were grouped into early predictors (age 0-16), comprising childhood, familial and individual characteristics; and later time-dynamic correlates of methamphetamine use in adulthood (ages 16-40). Generalised estimating equation models were fitted to identify predictors of methamphetamine use outcomes.

In adjusted models, paternal overprotectiveness and childhood anxious / withdrawn behavior were associated with any use of methamphetamine, but not regular use. Conversely, childhood conduct problems and parental illicit drug were associated with regular use but not any use. Male sex, high novelty seeking and deviant peer affiliations were associated with both any use and regular use in adjusted models. The strongest correlates of methamphetamine use in adulthood were unemployment, life stress and other substance use disorders (cannabis, nicotine, and alcohol).

Markers of externalizing problems in childhood and adolescence (conduct problems, high novelty seeking, parental illicit substance use, and deviant peer affiliations) are the strongest predictors of regular methamphetamine use in adulthood.