Psychological aggression, physical aggression, and injury in nonpartner relationships among men and women in treatment for substance-use disorders.

Objective: This study focused on the prevalence and predictors of psychological aggression, physical aggression, and injury rates in nonintimate partner relationships in a substance-use disorder treatment sample.
Method: The sample included 489 (76% men, 24% women) participants who completed screening measures for inclusion in a randomized control trial for an aggression-prevention treatment. Primary outcome measures included rates of past-year psychological aggression, physical aggression, and injury (both from the participant to nonpartners and from nonpartners to the participant). Potential predictors included individual factors (e.g., age, gender), developmental factors (e.g., family history of drug use, childhood physical abuse), and recent factors (e.g., depression, cocaine use).
Results: Rates of participant-to nonpartner psychological aggression (83%), physical aggression (61%), and injury (47%) were high, as were rates of nonpartner-to-participant aggression. Bivariate analyses revealed significant relationships between the aggression outcomes and most of the individual, developmental, and recent factors. However, multivariate analyses (zero-inflated Poisson regression) revealed that age, treatment status, current symptoms of depression, heavy periods of drinking, and cocaine use were related most frequently to the occurrence of aggression to and from nonpartners.
Conclusions: Nonpartner aggression may be as common within a substance-use disorder sample as partner aggression, and it is associated with heavy drinking episodes, cocaine use, and depressive symptoms. The findings highlight the need for the development of effective violence interventions addressing violence in nonpartner relationship types.