Parental transmission of risk for cannabis use disorders to offspring.

AIMS

We investigated the risk of cannabis use disorder (CUD) among probands as a function of parental psychopathology and explored parent-offspring gender concordance as a mechanism of parental CUD transmission to offspring.

DESIGN

Four waves of data collection from a longitudinal epidemiological study of psychopathology among a regionally representative sample.

SETTING

Participants were selected randomly from western Oregon, USA, and were initially assessed during mid-adolescence.

PARTICIPANTS

The reference sample included 719 probands and their biological mothers and fathers.

MEASUREMENTS

CUD episodes among probands were assessed with semistructured diagnostic interviews between mid-adolescence and young adulthood. Life-time psychiatric disorders among parents of probands were assessed when probands were approximately 24 years of age.

FINDINGS

There was an increased risk for CUD onset among probands with parental histories of CUD [hazard ratio (HR) = 1.93, 95% confidence interval (CI) = 1.30-2.88], hard drug use disorders (HR = 1.96, 95% CI = 1.32-2.90) or antisocial personality disorder (HR = 1.73, 95% CI = 1.06-2.82). A significant parent-offspring gender concordance effect indicated that females with a maternal CUD history were at higher risk for CUD onset compared with females without a maternal CUD (HR = 3.10, 95% CI = 1.52-6.34). Maternal CUD was not associated with CUD onset among males (P = 0.570), nor was there evidence for parent-offspring gender concordance effects for paternal CUD-specific transmission (P = 0.114).

CONCLUSIONS

Parental histories of antisocial personality and illicit substance use disorders are associated with increased risk for cannabis use disorder onset in offspring, especially among females with maternal cannabis use disorder histories.