Longitudinal Effects of Parental Psychiatric Diagnosis on Risk of Youth Binge-Drinking, Marijuana Use, and Cigarette Smoking

Background: Preventing substance use disorder (SUD) is a global priority. SUD is among the 25 leading causes of disability worldwide, and a quarter of all SUDs begin before age 18. Although parental psychiatric disorder (PPD) is associated with increased risk of child SUD, studies have primarily examined associations in the context of parental depression; the effects of other PPDs remain unknown. We address this research gap by examining associations over time between four PPDs (major depressive disorder [MDD], generalized anxiety disorder [GAD], social phobia [SPH], and posttraumatic stress disorder [PTSD]) and risk of three types of youth substance use (alcohol binge-drinking, marijuana use, and cigarette smoking). Methods: Our data consisted of seven waves of demographic, mental health, and substance use survey measures taken from a community sample of 282 Seattle youth ages 10-22 and their parents. All were recruited to The Intergenerational Project (TIP), an accelerated longitudinal study of intergenerational transmission of substance use and other problems. We used multilevel logistic regression to estimate the effects of PPD on risk of youth substance use, and assessed whether effects differed by youth age. All PPDs were assessed four times prior to and during the study by investigators using the Diagnostic Interview Schedule for DSM-IV. We examined two measures of PPD: (1) whether the parent ever met criteria (history), and (2) how many times the parent met criteria (chronicity). Covariates included parent substance use, youth ethnicity and gender, parent age at child birth, and receipt of public benefits. Results: In our baseline covariate models, the odds of all three types of youth substance use roughly doubled with every additional year of youth age. PTSD history was associated with five times the odds of binge-drinking (OR=5.22, p=0.01), but no other PDD history was significantly associated with any substance use risk. In our chronicity analysis, the odds of youth alcohol binge-drinking more than doubled for every additional year that a parent was diagnosed with SPH (OR=2.23, p=0.04) or PTSD (OR=2.52, p=0.01); no other PPD chronicity was significantly associated with any substance use risk. Several diagnosis-by-age interactions were significant. For every year increase in youth age, SPH predicted additional risk of both binge-drinking and cigarette smoking, while MDE and GAD predicted decreases in risk of marijuana and cigarette smoking, respectively. Implications: Our study identifies PTSD and SPH as possible risk factors for youth binge-drinking, suggesting that if a parent experiences these disorders, family mental health services may function as a substance use prevention strategy. We also find that child age may moderate some associations between PPDs and substance use risk, meaning that the timing of a family practitioner’s response to PDDs may depend on youth age and its attendant developmental and contextual factors. For example, if children exposed to parental SPH have more social difficulties with age, alcohol may play an increasing role in managing adult social life; thus, an early focus on building social skills and confidence may mitigate risk of problematic alcohol use in adulthood.