Do adolescent drug users fare the worst? Onset type, juvenile delinquency, and criminal careers

Although substance abuse often accompanies delinquency and other forms of antisocial behavior, there is less scholarly agreement about the timing of substance use vis-à-vis an individual's antisocial trajectory. Similarly, although there is extraordinary evidence that onset is inversely related to the severity of the criminal career, there is surprisingly little research on the offense type of onset or the type of antisocial behavior that was displayed when an individual initiated his or her offending career. Drawing on data from a sample of serious adult criminal offenders (N = 500), the current study examined 12 forms of juvenile delinquency (murder, rape, robbery, aggravated assault, burglary, larceny, auto theft, arson, weapons, sexual offense, drug sales, and drug use) in addition to age at arrest onset, age, sex, race to explore their association with chronicity (total arrests), extreme chronicity (1 SD above the mean which was equivalent to 90 career arrests), and lambda (offending per year). The only onset offense type that was significantly associated with all criminal career outcomes was juvenile drug use. Additional research on the offense type of delinquent onset is needed to understand launching points of serious antisocial careers.

A longitudinal analysis of the effects of a DRD4 polymorphism on marijuana use

The current study used a variable- and person-centered approach to examine whether a DRD4 polymorphism explained within-individual differences in frequency of marijuana use from adolescence into emerging adulthood. Data were analyzed from 1897 respondents from the genetic subsample of the National Longitudinal Study of Adolescent Health (Add Health) at waves I (ages 13-17), II (ages 14-18), and III (ages 21-25). Latent class growth model results revealed that marijuana use was characterized by four trajectories (non-users/experimenters, increasers, desisters, and chronic users), and that the DRD4 polymorphism differentiated increasers from non-users/experimenters. Overall, the results suggested that the DRD4 polymorphism may be relevant to differences in the developmental trajectories of marijuana use.