Data from prospective longitudinal studies have consistently shown that the onset of substance use in adolescence confers a particularly potent risk for persistent use and the development of substance use disorders (Bonomo et al., 2004; Brook et al., 1999; Duncan et al., 1997; Gil et al., 2004; Lewinsohn et al., 1999; McGue and Iacono, 2008; Timberlake et al., 2007). These data can provide another mechanism for examining possible generalized risk factors by comparing the probability of developing a SUD on substance A, given adolescent use of substance A versus adolescent use of substance B. For example, does smoking in adolescence primarily predict tobacco/nicotine dependence in young adulthood and only minimally predict problems with other substances (evidence of specific risk)? Alternatively, is adolescent smoking as predictive of later marijuana abuse or dependence as it is predictive of later nicotine dependence (evidence of generalized risk)? Using longitudinal data collected in adolescence and young adulthood, we asked whether the likelihood of developing an alcohol, tobacco, or marijuana SUD during young adulthood depends on adolescent drug involvement with a particular substance or any substance.
