Subjective and objective assessments of executive functions are independently predictive of aggressive tendencies in patients with substance use disorder

Background and aims

Impairments in executive functions have been found to influence violent behavior. Executive functions are crucial in the treatment of patients with substance use disorders because substance use generally impairs cognitive processes and is therefore detrimental for executive functions thereby reducing control of behavior and thus of consumption impulses. We studied correlations between subjective, i.e. self-report, and objective, i.e. behavior-based, assessment of executive functions and the predictive validity of these measures for aggression in patients with substance use disorder.

Methods

The study included 64 patients with a diagnosed substance use disorder who were convicted according to the German Criminal Code for crimes they committed in the context of their disorder and were therefore in treatment in forensic psychiatric departments in Germany. Multiple self-report and behavior-based instruments were used to assess executive functions, appetitive and facilitative aggression as well as clinical and sociodemographic variables.

Results

Participants showed impaired executive functions, and measures of executive functions predicted aggressive tendencies and violent offenses. Despite ecological validity of the findings, the subjective and objective assessments of executive functions did not correlate with each other, which corroborates studies in other clinical settings.

Conclusions

We discuss that this finding may be due to the conceptual differences between subjective and objective measures. Therefore, self-report and behavior-based measures should not be used as proxies of each other but as complementary measures that are useful for comprehensive diagnostics of cognitive impairments and assessment of risks for violent behavior.