Our findings of positive associations between BIP PRS and multiple levels of alcohol, cocaine, cannabis, and opioid involvement are consistent with observations of markedly elevated rates of substance use and use disorders in individuals with BIP (Compton et al., 2007), as well as with prior studies indicating a genetic origin of this comorbidity (Biederman et al., 2000; Johnson et al., 2009). Notably, when controlling for GENSUB, only a positive association between BIP PRS and non-problem cannabis use remained significant. This overall association with general, rather than specific, substance involvement liability may be reflective of similar cognitive mechanisms (e.g., impulsivity, emotion dysregulation, sensation-seeking) that are thought to broadly underlie both BIP and substance use disorders (Swann, 2010).
