Alcohol misuse and violent behavior: Findings from a 30-year longitudinal study

Abstract

Background: This study examined the associations between measures of alcohol abuse/dependence (AAD) and violent offending and intimate partner violence (IPV) to age 30 in a New Zealand birth cohort. Methods: Outcomes included: measures of violent offending, violence victimization, and physical IPV perpetration and victimization. The study also used measures of AAD symptoms; and time-dynamic covariate factors including life stress, other substance use, mental health status, peer and partner substance use and offending, and unemployment. Data were analysed using conditional fixed effects regression modelling augmented by time-dynamic covariate factors to control for confounding. Results: Those with five or more AAD symptoms had unadjusted rates of violence outcomes that ranged from 4.10 to 11.85 times higher than those with no symptoms, but these associations did not differ by gender. Adjustment of the associations for both unobserved fixed effects and time-dynamic covariate factors reduced the magnitude of the associations for violent offending, violence victimization and IPV perpetration, with those with five or more AAD symptoms having rates of violence outcomes that were 1.91-3.58 times higher than those with no symptoms. However, control for both fixed effects and time-dynamic covariate factors reduced the associations between AAD symptoms and physical IPV victimization to statistical non-significance (IRR. =0.73, 95% CI: 0.51-1.06). Conclusions: The results suggest a causal association between alcohol misuse and violent offending/victimization and IPV perpetration, with estimates suggesting that alcohol use disorder accounted for approximately 4.6-9.3% of the reported violent offending/victimization and IPV perpetration in the cohort.