Executive functions and substance use: Relations in late adolescence and early adulthood.

Poor executive functions (EFs) have been linked to substance use and abuse across multiple substances. However, it is unclear whether these associations are stronger for some EFs over others and/or some stages of substance use over others (e.g., ever using substances vs. dependence). It is also unknown whether such patterns change from adolescence to early adulthood, a transition that is characterized by changes to both EFs and substance use behaviors. In this longitudinal study of approximately 850 twins, we examined the relations between multiple EF abilities (including a common EF factor predicting 9 EF tasks) and measures of general substance use and dependence/abuse in late adolescence (mean age 17 years) and early adulthood (mean age 23 years). At the phenotypic level, common EF in adolescence was negatively related to the number of substances ever used and to last 6-month frequency of use, but not to dependence/abuse vulnerability (i.e., the number of dependence and abuse symptoms endorsed per substance that had been repeatedly used). However, in the same participants in early adulthood, common EF was only weakly related to the number of substances used, and not related to concurrent frequency of use nor dependence/abuse vulnerability. Twin analyses revealed that these associations were primarily genetic in origin, and that the genetic correlations were relatively stable over time. These results suggest that low common EF is a genetic risk factor for increased polysubstance use in late adolescence, but that non-EF factors play a larger role in the progression to substance dependence/abuse. (PsycINFO Database Record