Individuals who suffer abuse as children are more likely to use marijuana or cocaine later in life, a study from the United States has found.

The authors performed a secondary data analysis using information from the National Longitudinal Study of Adolescent to Adult Health.

A nationally representative sample of individuals aged between 11 and 21 years were interviewed in 1994-95 (adolescence), and again in 2001-2, when aged 18-28 (emerging adulthood), and finally in 2007-8 when aged 24-34 (established adulthood). Data for all three interviews were available for 12,288 participants.

The study identified nine typologies of self-reported childhood trauma: neglect; emotional, physical and sexual abuse; parental incarceration; parental binge drinking; witnessing, being threatened and experiencing violence.

Just over half the participants (53%) had experienced at least one childhood trauma. Emotional abuse was the most commonly reported trauma (16%), followed by neglect (12.4%) and being threatened with violence (12.1%).

There was a dose-response relationship between the number of traumas experienced and drug use at all three life stages, adolescence, emerging adulthood and adulthood, for both marijuana and cocaine.

The adjusted odds ratio (AOR) for marijuana use in adolescence when there had been one trauma versus none was 1.65 (95% CI: 1.42-1.92) while for four or more traumas versus none it was 6.92 (95% CI: 5.17-9.26); P < 0.0001 for trend.

The AOR for cocaine use in adolescence for one trauma versus none was 1.87 (95% CI: 1.23-2.84) and for four or more traumas versus none 9.54 (95% CI: 5.93-15.38); P < 0.0001 for trend.

Each individual trauma typology was independently associated with either marijuana or cocaine use in adolescence, emerging adulthood and/or adulthood.

The experience of abuse during childhood may be associated with a number of adverse effects, of which substance misuse is one, with a clear dose-response relationship.

The authors of this study state that early identification of childhood emotional trauma and signposting to resources to support children and young people may help reduce the risk of substance misuse during later life.

Dr Jez Thompson

Scheidell JD, Quinn K, McGorray SP et al. Childhood traumatic experiences and the association with marijuana and cocaine use in adolescence through adulthood. Addiction 2018;113:44-56