[Encyclios]

What consequences in the treatment?

The scientific literature, and consequently the treatment proposal, has focused on aspects related to anxiety in Obsessive-Compulsive Disorder, but if we think about the symptom of fear of contagion, a question arises: what is the emotion that you want to avoid? That is, is the problem the fear of the disgusting stimulus, or the ease of feeling the disgust? The answer to this question gives clinicians the ability to intervene with more effective treatments. Both types of avoidance, of threat and disgust, generate compulsions, e.g., cleaning, but resolution of such compensatory behaviors comes through analysis of which emotion generated them.

For example, in a study by Verwoerd and collaborators (2013), it was shown that in a non-clinical sample, divided by low or high contagion avoidance scores, the cognitive error relates the likelihood that a stimulus is threatening to how disgusted the individual feels, corroborating the avoidance itself. Thus, this is the same cognitive error found in anxiety symptomatology: “I feel anxiety, then there is a threat” is equivalent to “I feel disgust, then there is contamination,” with the diference that different emotions come into play (Verwoerd et al., 2013). Thus, the cognitive error underlying avoidance may be common to the two types of emotional experience.

Evidence in Obsessive-Compulsive Disorder in favor of a distinction between avoidance in terms of fear in a situation assessed as threatening, and between avoidance of the situation that generates disgust, will be reported below.

First, clinical studies have established that negative affectivity, anxiety and depression, are not determinants of the link between Propensity to Disgust (PD) and contamination fear symptoms in Obsessive-Compulsive Disorder, whereas it is PD itself that is determinant (Olatunji et al., 2016, Melli at al., 2016, Melli et al., 2015b, Ludvick, Boshen & Neuman, 2015). Thus, anxiety is not one of the factors that statistically explain this link.

In a study by Melli et al. (2015a), the authors developed a scale to distinguish two possible dimensions within fear of contamination: avoidance of harm, and avoidance of disgust, to test whether threat or the emotion of disgust itself generates avoidance in a sample of patients with Obsessive-Compulsive Disorder. The scale was called the Contamination Fear Core Dimensions Scale (CFCDS), consisting of 8 items, 4 for harm avoidance and 4 for disgust avoidance. The individual is then asked to give a Likert scale score from 0 to 5 for each item. The authors found how disgust avoidance was associated with the symptom of contamination and mental contagion, while harm avoidance was more associated with the symptom of responsibility (Melli et al., 2015a).

Thus, they demonstrated how these two dimensions are distinct, though related, and both part of the fear of contamination. Furthermore, the strength of the study concerns the focus on motivational mechanisms of contamination avoidance, i.e., whether it is the motivation to avoid feeling disgust or fear toward a threat (Melli et al., 2015a).

Is it disgust that triggers avoidance or something else? For example, the role of obsessive thoughts as activators was investigated (Melli et al., 2016). The results showed that obsessive thoughts are not in fact mediators, but that there is a direct relationship between PD and fear of contagion. Even more interesting, the authors performed the study with a sample of patients with Obsessive-Compulsive Disorder, predicting how in the general sample only those who presented the symptom of contamination would show this pattern. A result that would have been unsurprising if a sample of only patients with the contamination symptom had been taken into account. Therefore, the authors emphasized that, in general, during the treatment of Obsessive-Compulsive Disorder, when there is the presence of fear of contamination, the patient’s propensity to disgust should be taken into account (Melli et al., 2016).

Thus, it is plausible to wonder about the role of PD in other symptoms. In a paper by Olatunji and collaborators (2016), consisting of three studies, it actually showed that depending on which measures are used, PD can more or less strongly explain symptoms of contamination or all other symptoms. In fact, in the first study that analyzes disgust propensity through the Disgust Scale, Obsessive-Compulsive Disorder symptoms through the Padua Inventory, and anxiety through the Anxiety Sensitivity Index-3, PD would explain more of the contamination symptoms of Obsessive-Compulsive Disorder, but mediated by anxiety. In the second proposed study, the Disgust Scale for PD, the Obsessive-Compulsive Inventory OCI-R for Obsessive-Compulsive Disorder symptoms, and the Depression Anxiety Stress Scale for anxiety, the relationship between PD and contagion symptoms is not significantly different from the relationship between PD and all other symptoms. Whereas in the third study where both PD and disgust sensitivity are considered, and DOC symptomatology measured through the Dimensional Obsessive-Compulsive Scale DOCS, both disgust dimensions are more strongly related to noncontagious symptoms, rather than contamination itself (Olatunji et al., 2016).