Maternal Cannabis Use During a Child's Lifetime Associated With Earlier Initiation.

Abstract

Earlier cannabis initiation is associated with more severe neuropsychiatric and social consequences. The authors investigated whether mothers' cannabis use is associated with earlier cannabis initiation by their children. Mother and child data were from the National Longitudinal Survey of Youth 1979 (1980-1998 waves) and Child and Young Adults (1988-2014 waves) cohorts, respectively. Cox proportional hazard models assessed the effect of maternal cannabis use prior to a child's adolescence on the child's risk of subsequent cannabis initiation. Models were stratified by race and child's age category (6-16, 17-24, ≥25 years). Adjusted analyses controlled for sociodemographic variables. Analyses were conducted in 2017. Median age of cannabis initiation for children of maternal ever users was age 16years compared with age 18years among children of maternal never users. Children of 1-year and multiple-year users were at increased risk of cannabis initiation between ages 6 and 16years (hazard ratio=1.38, p<0.001, and hazard ratio = 1.45, p<0.001, respectively). Effects were slightly stronger among non-Hispanic non-black children. As cannabis legalization expands across the U.S., adult use may become increasingly normative. This study indicates that maternal cannabis use may be a risk factor for early initiation among their offspring. Preventive interventions should consider strategies to delay initiation among children of cannabis users.