Greater Insight May Increase Hostility in Schizophrenia

Increased awareness of having a mental illness was strongly associated with hostile tendencies in patients with schizophrenia spectrum disorders, according to a study published in Schizophrenia Research. In addition, depression was found to be a mediating factor of insight.

Researchers sought to examine the relationship between insight and aggressiveness in patients with schizophrenia spectrum disorders. Investigators specifically analyzed emotional (anger) and cognitive (hostility) components of aggression to determine whether insight is a risk factor for aggressiveness in patients with schizophrenia.

Researchers recruited 666 participants aged 15 and older with schizophrenia spectrum disorder from a French national network of 10 schizophrenia expert centers. They collected sociodemographic data and clinical histories, and a multidisciplinary team interviewed and evaluated patients for aggressiveness using the Buss-Perry Aggression Questionnaire. Insight was measured using the Scale to assess Unawareness of Mental Disorder (SUMD) and the Birchwood Insight Scale (BIS), which assessed awareness of having a mental illness, consequences of illness, symptom attribution, and necessity of treatment.

According to the SUMD and BIS insight outcomes, more than 50% of the participants were aware of their illness (54.4%), the consequences of their illness (50.6%), or the necessity for treatment (55%). Hostility was most strongly associated with SUMD insights, in which patients aware of their illness were almost twice as likely to report hostile traits than patients who were unaware (OR 1.95; 95% CI, 1.08-3.5). Conversely, awareness of illness consequences was associated with lower anger, while awareness of treatment necessity was associated with lower verbal aggressiveness. Patients who were only moderately aware of the consequences of their illness had a higher likelihood of reporting anger (OR 2.63; 95% CI, 1.42-4.86) and physical aggressiveness (OR 2.47; 95% CI, 1.33-4.6).

A limitation of the study was the cross-sectional design that prevents inferences of causality in the associations found between insight and aggressiveness. The cohort was drawn from expert clinical centers and the findings may not be generalizable to a greater population. Finally, data on medication use and substance abuse was limited for the cohort.

Insight and aggressiveness are multi-dimensional concepts and the study findings suggest that specific dimensions of aggressiveness are related to insight in patients with schizophrenia. Hostility was most strongly associated with insight, in which hostile tendencies are triggered with increasing awareness. Depression, however, was a confounding factor in the relationship between insight and aggressiveness and is explained by self-stigma as a mediating factor between better insight and depression. Future studies are needed to explore the underlying mechanisms between insight and aggressiveness.

Reference                                                                                                                       

Schandrin A, Norton J, Raffard S, et al. A multi-dimensional approach to the relationship between insight and aggressiveness in schizophrenia: findings from the FACE-SZ cohort [published online August 3, 2018]. Schizophr Res. doi: 10.1016/j.schres.2018.07.029