(PS7-C53) Is Sympathetic Magic an Obsessive-compulsive Disorder Endophenotype? Examination of OCD Participants, First-degree Relatives, and Healthy Controls

Obsessive-compulsive disorder (OCD) is characterized by persistent, distressing thoughts and repetitive behaviors (APA, 2022). Sympathetic magic is a unique clinical feature of OCD and entails maladaptive beliefs that contaminated objects may be permanently contagious or that contamination from one object to another is nearly absolute (Tolin & Meunier, 2007). Such beliefs contribute to a frequent overestimation of contamination threat and are thought to facilitate the avoidance of disease (Tolin & Meunier, 2007). However, sympathetic magic is an understudied phenomenon in OCD, such that the heritable features and potential mechanisms remain largely unknown. Indeed, it is unclear if sympathetic magic beliefs function as an endophenotype for OCD. Given that endophenotypes are measurable markers of genetic vulnerability to current or future disorder, this may have important implications for conceptualizing risk for OCD. Accordingly, the present study examined whether sympathetic magic functions as an endophenotype for OCD, through which unaffected, first-degree relatives of individuals with OCD experience higher levels of sympathetic magic compared to the general population (Gottesman & Gould, 2003). The present study also examined perceived vulnerability to disease as a potential mechanism that explains heightened sympathetic magic beliefs in OCD. The final sample (N = 81) consisted of 30 individuals with OCD, 26 first-degree relatives, and 25 age-matched healthy controls. During session 1, participants completed a diagnostic interview (Sheehan et al., 1998) and the Perceived Vulnerability to Disease Questionnaire (PVD; Duncan et al., 2009). During session 2, participants completed a sympathetic magic task (Tolin et al., 2004) which consisted of an experimenter rubbing a clean pencil on a contaminated toilet, then rubbing the clean pencil on a second pencil and collecting contamination ratings. This process continued for 12 pencils (i.e., 12 degrees of removal from original contagion). The contamination scores for the three groups followed a similar profile and yielded a non-significant interaction, F(22, 138) = .75, p > .10, suggesting the slopes for each diagnostic group did not significantly differ from one another. However, there was a significant difference between the groups on percent reduction of contamination on the task over time, F(2,79) = 3.03, p < .05, such that the OCD group reported significantly less reduction in contamination ratings across the 12 pencils than healthy controls (p = .02) but did not significantly differ from their first-degree relatives (p > .10). However, relatives did not significantly differ from healthy controls (p = .10). Consistent with a disease-avoidance model, PVD was found to significantly mediate the relationships between diagnostic status (OCD vs. relatives; OCD vs. controls) and percent reduction in contamination ratings on the task (ps < .02). Although these findings suggest that sympathetic magic may not function as a distinct endophenotype for OCD, it does appear to be an important part of the underlying pathology of the disorder. Clinical implications will be discussed.