The Association of Parent's Marijuana Use during Three Developmental Periods and Child's Marijuana Use during Adolescence

Introduction: There is a strong assumption of intergenerational (IG) continuity for drug use and related problem behaviors and, empirically, there are significant IG associations for alcohol and drug use (Knight et al., 2014), criminality (Farrington et al., 2001), family violence (Ireland & Smith, 2009), and other problem behaviors. Nevertheless, understanding how parents and offspring are linked is more complex than the simple notion that children follow in parental footsteps.  More fine-grained analysis of the nature of IG continuity and discontinuity is needed.  For example, we need a better understanding of how the timing of a parent’s substance use (even before becoming a parent) may influence a child’s substance use. In this study, we examine whether the timing of parent’s marijuana use (during adolescence, during the transition to adulthood, and when their child is in pre-adolescence), is associated with their child’s course of marijuana use during adolescence.

Methods: Data come from the Rochester Youth Development Study and the Rochester Intergenerational Study, companion studies of three generations of families who were living in Rochester, NY in 1986.  The original focal adolescent (G2) and their firstborn child (G3) are considered here (N=414 parent-child pairs).  The sample is predominantly African American, and families living in higher crime neighborhoods at the start of the study were oversampled. The independent variable is G2 use of marijuana.  We consider frequency of use during three periods of time (G2 adolescent use, G2 use during the transition to adulthood, and G2 use when G3 was in pre-adolescence).  The dependent variable is past year use of marijuana by G3 from ages 12 to 21. Random intercept logistic growth models were used to estimate the models.

Results: Adjusting for demographic and socio-economic background variables, we find evidence of intergenerational continuity in marijuana use.  Greater use of marijuana by G2 in each of the developmental periods is significantly (p<.05) associated with greater odds of marijuana use by G3 throughout adolescence.

Conclusions:  Our findings provide evidence of intergenerational continuity in marijuana use, and indicate that a parent’s use of marijuana during their adolescence, their transition to adulthood, and when their child is approaching adolescence is associated with an increased likelihood that their child will use marijuana during adolescence.