Anger regulation in patients with functional neurological disorder: A systematic review.

Background: Functional neurological disorder (FND) has been associated with predisposing psychological factors, including dysregulation of anger-related processes. This paper provides a systematic review of the literature on anger regulation in FND. We evaluated anger-related research on patient self-report, observational, and laboratory based measures in FND. The review also addresses adverse childhood experiences and their relation with anger regulation, and the effects of therapies targeting anger regulation in FND.

Methods: MEDLINE, EMBASE, and PsycINFO were searched for both quantitative and qualitative research, published in a peer-reviewed journal with a sample size of at least 5 (registered under Prospero protocol CRD42022314340).

Results: A total of 2200 articles were identified. After screening, 54 studies were included in this review (k = 20 questionnaire-based studies, k = 12 laboratory studies, k = 21 using other methods, and k = 1 used both questionnaires and other methods) representing data of 2502 patients with FND. Questionnaire-based studies indicated elevated levels of state anger and trait hostility in patients with FND. Laboratory studies showed a higher tendency to avoid social threat cues, attentional bias towards angry faces, difficulties reliving anger, and preoccupation with frustrating barriers among FND patients versus controls. No specific childhood experiences were identified related to anger regulation in FND, and too few small and uncontrolled studies were available (k = 2) to assess the effects of anger-related interventions in FND. The overall quality of the studies was fair (k = 31) to poor (k = 18). Five studies (k = 5) were rated as having a good quality.

Conclusions: This review suggests that patients with FND have maladaptive anger regulation compared to individuals without FND. The findings also highlight the need for further research on the prevalence and consequences of anger-related processes in the development, diagnosis and treatment of FND.