Mediational Pathways From Genetic Risk to Alcohol Use Disorder in Swedish Men and Women

The purpose of this study was to clarify the mediational pathways from genetic risk for alcohol use disorder (AUD) to AUD itself.

Using information on AUD status from first- through fourth-degree relatives obtained from national registries, we created a genetic risk score for AUD for the Swedish population. We first tested a simple mediational path model in males and females separately, with early onset externalizing psychopathology (EPP), internalizing psychopathology (IPP), and poor educational attainment (EA). We then tested a more complex model in a smaller, older sample of males that contained additional self-report measures from late adolescence.

In our basic model, the largest mediational pathway from AUD genetic risk to AUD in both sexes was via high EPP followed by low EA and high IPP. The EPP pathway was considerably stronger in males, the low EA pathway was modestly stronger in females, and the IPP pathway was identical in both sexes. Our more complex model replicated the strong externalizing pathway to AUD, showing that it connected to key downstream risk factors such as early drug and alcohol use and low resilience.

Our models concurred in showing that the strongest mediational pathway for genetic risk to AUD includes externalizing symptoms and disorders, which in turn predict further key downstream risk factors. Pathways through lower EA and IPP had smaller effects. IPP had mixed effects (partly predisposing and partly protective) on downstream risk factors. The largest sex difference was a stronger externalizing pathway to genetic risk to AUD in males than in females.