Disgust propensity and contamination-related OCD symptoms: The mediating role of mental contamination

• Recent research has supported the notion of mental contamination (MC).
• Evidence supported the role of disgust propensity (DP) in contamination-related OCD (OCD-C).
• Our aim was to investigate the association between MC, DP and OCD-C in a clinical sample.
• Significant correlations were found between DP, MC and OCD-C symptoms.
• Mediation analysis indicated that MC plays a mediating role in this relationship.

Fear of contamination within obsessive compulsive disorder (OCD) is traditionally conceptualized as a physical phenomenon. Research has also supported the notion of mental contamination (MC), in which people feel contaminated in the absence of contact with a physical pollutant. In the last decades, a growing number of studies has been centered on the role of disgust propensity (DP) in contamination-related OCD (OCD-C) symptoms. However, the relationship between MC, DP and OCD-C symptoms has not been thoroughly explored. The aims of this study were: (1) to investigate the prevalence of MC in a sample of OCD-C patients; (2) to explore the association between MC, DP and OCD-C symptoms in a sample of OCD patients; and (3) to analyze the role of MC as a mediator in this relationship. Sixty-three patients with OCD-C symptoms completed a series of self-report questionnaires that assessed mental contamination, disgust propensity, OCD symptoms, anxiety, and depression. Significant correlations were found between DP, MC and OCD-C symptoms, controlling for anxiety and depression. Mediation analysis indicated that MC plays a mediating role in the relationship between DP and OCD-C symptoms. These data support the need for specific assessment of MC in clinical settings, particularly where feelings of disgust are involved.