The COVID-19 pandemic and obsessive-compulsive disorder: a systematic review of comparisons between males and females

Coronavirus disease, one of the most disastrous epidemics, has caused a worldwide crisis, and the containment measures applied to decelerate the progression of the pandemic can increase the risk of obsessive-compulsive disorder (OCD). Identifying vulnerable groups in this area can lead us to better resource expenditure, and therefore, this systematic review aims to make a comparison between males and females to determine which of the two groups was most affected by the COVID-19 pandemic regarding OCD. Also, a meta-analysis was designed to investigate the prevalence of OCD during the COVID-19 pandemic. A comprehensive search was conducted among three databases (Medline, Scopus, Web of Science) until August 2021 which resulted in 197 articles, and 24 articles met our inclusion criteria. Overall, more than half of the articles stated the role of gender in OCD during the COVID-19 pandemic. Several articles emphasized the role of the female gender, and some others the role of the male gender. The meta-analysis revealed a 41.2% overall prevalence of OCD during the COVID pandemic and 47.1% and 39.1% OCD prevalence for female and male genders respectively. However, the difference between the two genders was not statistically significant. Generally, it seems that females are at greater risk of OCD during the COVID-19 pandemic. In the following groups, the female gender may have acted as a risk factor: under-18 years students, hospital staff, and the studies in the Middle East. In none of the categories, male gender was clearly identified as a risk factor.

Obsessive-Compulsive Disorder During the COVID-19 Pandemic-A Systematic Review

BACKGROUND

The COVID-19 pandemic and its associated restrictions may contribute to a deterioration in mental health; individuals with obsessive-compulsive disorder (OCD) may be particularly affected. This systematic review aimed to investigate the effects of the current pandemic on people diagnosed with OCD, and whether pandemics may affect the development of OCD symptoms.

METHODS

We conducted a systematic search using NCBI PubMed, SCOPUS, and Google Scholar on February 9, 2021. Research articles related to OCD and COVID-19 or other pandemics were attempted to be identified using pre-defined search terms. Case reports, clinical guidelines, letters, and clinical research articles including ≥100 participants were included; reviews were excluded. The systematic review adheres to PRISMA guidelines and the Newcastle-Ottawa Scale was used to assess the quality of the included clinical research articles.

RESULTS

A total of 79 articles were included in the full-text assessment. Of these, 59 were clinical research articles, two were clinical guidelines, six were case reports, and 12 were letters. The research articles examined OCD symptoms in adult patients with diagnosed OCD, the general population, pregnant women, healthcare workers, students, and young adults, children, and adolescents. Only one study on OCD in previous pandemics was identified.

CONCLUSION

This systematic review found that people both with and without diagnosed OCD prior to the pandemic generally experienced a worsened landscape of symptoms of OCD during the COVID-19 pandemic. However, the responses are heterogeneous and many factors other than the pandemic seemed to affect the development of OCD symptoms. To prevent the impairment of symptoms and the development of new cases, close monitoring of patients with OCD and education of the general public is essential. Literature is still limited; thus, multinational and cross-cultural, longitudinal studies are warranted to gain further insights on this topic.

Fear conditioning and extinction in obsessive-compulsive disorder: A systematic review

Laboratory experiments using fear conditioning and extinction protocols help lay the groundwork for designing, testing, and optimizing innovative treatments for anxiety-related disorders. Yet, there is limited basic research on fear conditioning and extinction in obsessive-compulsive disorder (OCD). This is surprising because exposure-based treatments based on associative learning principles are among the most popular and effective treatment options for OCD. Here, we systematically review and critically assess existing aversive conditioning and extinction studies of OCD. Across 12 studies, there was moderate evidence that OCD is associated with abnormal acquisition of conditioned responses that differ from comparison groups. There was relatively stronger evidence of OCD's association with impaired extinction processes. This included multiple studies finding elevated conditioned responses during extinction learning and poorer threat/safety discrimination during recall, although a minority of studies yielded results inconsistent with this conclusion. Overall, the conditioning model holds value for OCD research, but more work is necessary to clarify emerging patterns of results and increase clinical translational utility to the level seen in other anxiety-related disorders. We detail limitations in the literature and suggest next steps, including modeling OCD with more complex conditioning methodology (e.g., semantic/conceptual generalization, avoidance) and improving individual-differences assessment with dimensional techniques.

Acquisition and maintenance of disgust reactions in an OCD analogue sample: Efficiency of extinction strategies through a counter-conditioning procedure

BACKGROUND

Obsessive-compulsive disorder (OCD) has long been considered as an anxiety disorder, disgust is the dominant emotion in contamination-based OCD. However, disgust seems resistant to exposure with response prevention partly due to the fact that disgust is acquired through evaluative conditioning.

AIMS

The present research investigates a counter-conditioning intervention in treating disgust-related emotional responses in two groups of individuals with high (High contamination concerns, HCC, n = 24) and low (Low contamination concerns LCC, n = 23) contamination concerns.

METHODS

The two groups completed a differential associative learning task in which neutral images were followed by disgusting images (conditioned stimulus; CS+), or not (CS-). Following this acquisition phase, there was a counter-conditioning procedure in which CS+ was followed by a very pleasant unconditional stimulus while CS- remained unreinforced.

RESULTS

Following counter-conditioning, both groups reported significant reduction in their expectancy of US occurrence and reported less disgust with CS+. For both expectancy and disgust, reduction was lower in the HCC group than in the LCC group. Disgust sensitivity was highly correlated with both acquisition and maintenance of the response acquired, while US expectation was predicted by anxiety.

CONCLUSION

Counter-conditioning procedure reduces both expectations and conditioned disgust.

Evaluating the mediating effects of perceived vulnerability to disease in the relation between disgust and contamination-based OCD

Contamination-based obsessive-compulsive disorder (OCD) is thought to develop and be maintained by excessive propensity to experience disgust, particularly in response to perceived contaminants, and dysfunctional threat appraisals pertaining to illness. The present studies attempted to integrate these lines of research by testing the degree to which contamination-based OCD is associated with individual differences in disgust propensity and sensitivity, affective distress in response to perceived contaminants, and perceived threat of illness. In Study 1, a convenience sample of 185 adults completed self-report scales assessing obsessive-compulsive symptoms, disgust propensity and sensitivity, germ aversion, and perceived infectability. Multivariate regression showed that disgust propensity and germ aversion were the only significant predictors of contamination-based obsessions and compulsions. Exploratory analyses suggested that there was a significant indirect effect of disgust propensity on contamination-based obsessions and compulsions via germ aversion. Findings from Study 1 were replicated using a sample of twenty-six obsessive-compulsive participants. Despite the substantially smaller sample, the proportion of the total effects attributable to the mediating effect of germ aversion was comparable, consistent with a significant partial mediation in both samples. These results together suggest that contamination-based OCD symptoms are likely maintained and motivated by basic affective processes.

Incompleteness and Disgust Predict Treatment Outcome in Pediatric Obsessive-Compulsive Disorder

Increasing evidence suggests that pediatric obsessive-compulsive disorder (OCD) is motivated not only by fear but also by feelings of incompleteness and disgust. However, it is currently unclear whether emotion involvement in OCD symptoms is associated with treatment response in youth with OCD. The present study examined whether treatment outcome for youth with OCD was predicted by the degree to which fear, disgust, and incompleteness were involved in baseline OCD symptoms. Children and adolescents with OCD entering treatment for this condition (N = 111) were administered standardized OCD symptom measures and an interview designed to assess the degree of fear, incompleteness, and disgust experienced during current OCD symptoms. Follow-up assessments occurred on average 13 months after baseline with each participant coded for outcome according to internationally acknowledged change criteria for pediatric OCD. Higher levels of incompleteness and disgust as part of baseline OCD symptoms predicted poorer outcome. The degree of fear during baseline OCD symptoms did not predict outcome. If replicated under controlled conditions, these results suggest that incompleteness and disgust may act as barriers to improvement in pediatric OCD and that treatment modifications that target these emotion-related motivators may improve outcome for a subset of youth.

But first, coffee: The roles of arousal and inhibition in the resistance of compulsive cleansing in individuals with high contamination fears

Inhibition plays a crucial role in reducing intrusive thoughts and compulsive behaviors, such as handwashing, in response to the feeling of disgust. The current study examines whether manipulating arousal can facilitate inhibition and the resistance of compulsive cleansing. Forty-seven participants with high contamination fears were recruited for this study. Participants were divided into a caffeine group or a no-caffeine group. Participants touched a potentially contaminated and disgusting stimulus ("dirty" diapers) and were asked to wait as long as they could before washing their hands. Only the caffeine group exhibited greater pre-post stop-signal reaction time improvement in the stop-signal task, indicating improved inhibition. Participants in the caffeine group exhibited significantly lower subjective distress and urges-to-wash their hands both after touching the stimulus and while waiting to engage in the cleansing behavior. Similarly, the caffeine group resisted the urge to compulsively cleanse for about twice as long as those in the no-caffeine group. Time spent washing, subjective distress levels, and urge-to-wash levels after participants washed their hands were similar between groups. The current findings support the notion that increased arousal improves inhibition, which may play a role in improving our ability to resist intrusive disgust and compulsive cleansing behaviors.

Long-term modulation of cardiac activity induced by inhibitory control over emotional memories

Efforts to exclude past experiences from conscious awareness can lead to forgetting. Memory suppression is central to affective disorders, but we still do not really know whether emotions, including their physiological causes, are also impacted by this process in normal functioning individuals. In two studies, we measured the after-effects of suppressing negative memories on cardiac response in healthy participants. Results of Study 1 revealed that efficient control of memories was associated with long-term inhibition of the cardiac deceleration that is normally induced by disgusting stimuli. Attempts to suppress sad memories, by contrast, aggravated the cardiac response, an effect that was closely related to the inability to forget this specific material. In Study 2, electroencephalography revealed a reduction in power in the theta (3-8 Hz), alpha (8-12 Hz) and low-beta (13-20 Hz) bands during the suppression of unwanted memories, compared with their voluntary recall. Interestingly, however, the reduction of power in the theta frequency band during memory control was related to a subsequent inhibition of the cardiac response. These results provide a neurophysiological basis for the influence of memory control mechanisms on the cardiac system, opening up new avenues and questions for treating intrusive memories using motivated forgetting.

The impact of the COVID-19 pandemic on patients with OCD: Effects of contamination symptoms and remission state before the quarantine in a preliminary naturalistic study

The containment measures implemented to reduce the progression of the COVID-19 pandemic can increase the risk of serious mental disorders, including obsessive-compulsive disorder (OCD). The general fear of getting infected and the importance given to personal hygiene, may have a negative impact on this clinical population. In a group of patients with OCD who had completed an evidence-based therapeutic path for OCD before the quarantine, this study evaluated the changes on OCD symptoms during the quarantine and investigated the effects of contamination symptoms and remission state before the quarantine on OCD symptom worsening during the quarantine. The Yale-Brown Obsessive Compulsive (Y-BOCS) Severity score, administered before the quarantine, was re-administered after six weeks since the beginning of the complete lockdown. A significant increase in obsession and compulsion severity emerged. Remission status on OCD symptoms and having contamination symptoms before the quarantine were significantly associated with more elevated OCD symptom worsening during the quarantine. To our knowledge, this is the first study which assessed OCD symptoms at the COVID-19 time. Our results support the need to improve relapse prevention during the period of social restrictions and develop alternative strategies such as online consultations and digital psychiatric management.

A Meta-Analysis on the Efficacy of Exposure-Based Treatment in Anxiety Disorders: Implications for Disgust

Despite of several meta-analyses indicating that exposure-based treatments (EBT) are successful in addressing anxiety and fear symptoms, less is known whether this is also the case for disgust, which also accompanies anxiety disorders. Therefore, the aim of the current meta-analysis was to compare the efficacy of EBT on disgust and anxiety (emotional distress), against control condition. This meta-analysis included a total of eight studies. Overall, there was a medium effect size (g = .57, 95% CI: .26 to .88, p < .001) for emotional distress; a medium effect size for anxiety (g = .79, 95% CI: .24 to 1.34, p = .005), yet a small effect size for disgust (g = .36, 95% CI: .05 to .68, p = .024). These findings prompt that current EBT are not tailored to address disgust symptoms accompanying many forms of anxiety disorders, although literature points more and more to a need in this respect. We also examined potential moderator variables (the year of publication, the number of exposure sessions, age of the sample, and gender composition). Additionally, we discussed several strengths and limitations, one of the most important being the small number of studies regarding the subject and their heterogeneity.

Indignation for moral violations suppresses the tongue motor cortex: preliminary TMS evidence

We commonly label moral violations in terms of ‘disgust’, yet it remains unclear whether metaphorical expressions linking disgust and morality are genuinely shared at the cognitive/neural level. Using transcranial magnetic stimulation (TMS), we provide new insights into this debate by measuring motor-evoked potentials (MEPs) from the tongue generated by TMS over the tongue primary motor area (tM1) in a small group of healthy participants presented with vignettes of moral transgressions and non-moral vignettes. We tested whether moral indignation, felt while evaluating moral vignettes, affected tM1 excitability. Vignettes exerted a variable influence on MEPs with no net effect of the moral category. However, in accordance with our recent study documenting reduced tM1 excitability during exposure to pictures of disgusting foods or facial expressions of distaste, we found that the vignettes of highly disapproved moral violations reduced tM1 excitability. Moreover, tM1 excitability and moral indignation were linearly correlated: the higher the moral indignation, the lower the tM1 excitability. Respective changes in MEPs were not observed in a non-oral control muscle, suggesting a selective decrease of tM1 excitability. These preliminary findings provide neurophysiological evidence supporting the hypothesis that morality might have originated from the more primitive experience of oral distaste.

A Psycho-Behavioral Perspective on Modelling Obsessive-Compulsive Disorder (OCD) in Animals: The Role of Context

Obsessive-compulsive disorder is a heterogeneous and debilitating condition, characterized by intrusive thoughts and compulsive repetition. Animal models of OCD are important tools that have the potential to contribute significantly to our understanding of the condition. Although there is consensus that pre-clinical models are valuable in elucidating the underlying neurobiology in psychiatric disorders, the current paper attempts to prompt ideas on how interpretation of animal behavior can be expanded upon to more effectively converge with the human disorder. Successful outcomes in psychopharmacology involve rational design and synthesis of novel compounds and their testing in well-designed animal models. As part of a special journal issue on OCD, this paper will 1) review the psychobehavioral aspects of OCD that are of importance on how the above ideas can be articulated, 2) briefly elaborate on general issues that are important for the development of animal models of OCD, with a particular focus on the role and importance of context, 3) propose why translational progress may often be less than ideal, 4) highlight some of the significant contributions afforded by animal models to advance understanding, and 5) conclude by identifying novel behavioral constructs for future investigations that may contribute to the face, predictive and construct validity of OCD animal models. We base these targets on an integrative approach to face and construct validity, and note that the issue of treatment-resistance in the clinical context should receive attention in current animal models of OCD.

The Role of Perceived Control in the Psychophysiological Responses to Disgust of Subclinical OCD Women

Obsessive‒compulsive disorder (OCD), and especially contamination obsessions and washing compulsions, has been related to disgust. However, when its cardiovascular correlates have been studied, contradictory results have been found, including heart rate accelerations and decelerations. The aim of this study is to analyze emotional, cognitive, and cardiovascular responses in nonclinical (control) and subclinical participants with obsessive‒compulsive contamination/washing symptoms when confronted with a disgusting stimulus. Twenty-seven participants (14 subclinical OCD) completed a behavioral avoidance task with a contamination-based stimulus while their heart rate and subjective variables were measured. Results showed heart rate reductions in both samples, whereas subjective measures reflected higher disgust, anxiety, dirtiness, and emotional valence in the subclinical sample. However, at the same time, the sense of dominance was lower in the control group. In conclusion, our results support a heart rate deceleration during exposure to a disgusting stimulus dissociated from the subjective experience.

Is Heightened Disgust Propensity Truly a Risk Factor for Contamination-Related Obsessive-Compulsive Disorder?

Disgust propensity (DP) has been conceptualized as a stable personality trait that confers risk for contamination-related OCD (C-OCD). However, the extent to which DP leads to the subsequent development of C-OCD is unclear. In fact, the presence of C-OCD might lead to an increase in DP rather than the inverse. The present study was aimed to test this hypothesis in a large clinical sample of OCD patients (≥ 21 years of age) with (C-OCD; n = 56) and without (NC-OCD; n = 103) contamination-related symptoms that completed measures of OCD symptoms, depression, anxiety, and DP. DP was assessed twice, in reference to the present situation (T1) and to when the participant was 18 years old (T0). The two groups did not significantly differ in DP at T0. However, C-OCD participants reported higher DP scores than NC-OCD at T1. Furthermore, the T1 vs T0 difference in DP was significant only in the C-OCD group. Subsequent analyses also showed that T1 DP levels, but not T0 levels, significantly predicted contamination-related symptoms. Despite study limitations, these findings question the role of DP as a risk factor for C-OCD.

Disgust sensitivity mediates the effects of race on contamination aversion

African Americans report greater contamination aversion than European Americans. Few studies have attempted to identify potential causes for this elevated contamination aversion, though existing research and theory suggests this may be partly due to concomitant heightened disgust sensitivity. The present study examined the relations between race, disgust sensitivity, and contamination aversion among African and European Americans. A convenience sample of fourhundred and twenty-nine participants completed the Disgust Scale - Revised (DS-R) and the Padua Inventory - Revised (PI-R). African Americans endorsed greater disgust sensitivity (DS-R total) - particularly on the core and contamination subscales of the DS-R - and scored higher on the contamination subscale of the PI-R (but not on other subscales) than European Americans. Mediational analyses revealed a significant total effect of race on contamination aversion and a significant indirect effect of race on contamination aversion through disgust sensitivity; the direct effect of race on contamination aversion remained significant even after controlling for race. These findings suggest that elevated contamination aversions among African Americans may be partly due to elevated disgust sensitivity. If confirmed with larger and clinical samples, and more robust experimental methods, this relationship may prove to have implications for the treatment of contamination-based obsessive-compulsive disorder (OCD) among African Americans.

Core, social and moral disgust are bounded: A review on behavioral and neural bases of repugnance in clinical disorders

Disgust is a multifaceted experience that might affect several aspects of life. Here, we reviewed research on neurological and psychiatric disorders that are characterized by abnormal disgust processing to test the hypothesis of a shared neurocognitive architecture in the representation of three disgust domains: i) personal experience of 'core disgust'; ii) social disgust, i.e., sensitivity to others' expressions of disgust; iii) moral disgust, i.e., sensitivity to ethical violations. Our review provides some support to the shared neurocognitive hypothesis and suggests that the insula might be the "hub" structure linking the three domains of disgust sensitivity, while other brain regions may subserve specific facets of the multidimensional experience. Our review also suggests a role of serotonin core and moral disgust, supporting "neo-sentimentalist" theories of morality, which posit a causal role of affect in moral judgment.

Contamination-Focused Exposure as a Treatment for Disgust-Based Fears: A Preliminary Test in Spider-Fearful Women

Background: Disgust is thought to play a prominent role in multiple anxiety disorders and fears, including spider phobia, though little attention has been given to specific treatment strategies that may be effective for multiple disgust-based fears. Aims: In the present study, we evaluated contamination-focused exposure as a potential transdiagnostic treatment strategy for disgust-based fears in a spider fearful sample. Method: Women with significant spider fear were randomized to three 30-minute sessions of exposure therapy involving repeated contact with a dirt mixture (n=17) or a waitlist control condition (n=17). Assessments of spider fear and disgust were administered at baseline and at one-week posttreatment. Results: At high (but not low) levels of pretreatment disgust propensity, exposure led to lower in vivo spider fear and perceived danger than waitlist, though exposure had no effects on spider-related disgust. Similar effects of exposure on spider fear were found at high levels of pretreatment spider-related disgust. Exposure also reduced fear and danger perceptions, but not disgust, related to a separate contamination assessment (touching a toilet). No effects of treatment were found on self-report measures of spider fear or disgust propensity. Conclusions: These findings suggest contamination-focused exposure therapy may be an effective transdiagnostic treatment strategy for individuals with elevated disgust propensity. Limitations and directions for future research are discussed.

Ondansetron augmentation in patients with obsessive-compulsive disorder who are inadequate responders to serotonin reuptake inhibitors: improvement with treatment and worsening following discontinuation

OBJECT

The aim of this study was to evaluate low-dose ondansetron as an augmentation strategy in patients with obsessive-compulsive disorder (OCD) who do not adequately respond to serotonin reuptake inhibits (SRIs).

METHODS

Twenty-one OCD patients who had not responded adequately to an SRI received 12 weeks of single-blind ondansetron augmentation initiated at 0.25mg BID for 2 weeks, and titrated to 0.5mg BID for an additional 10 weeks. Patients were rated every two weeks using the Yale-Brown Obsessive Compulsive Scale (YBOCS) and Clinical Global Impressions Scale (CGI). Treatment response was defined as an additional 25% reduction in YBOCS score from the score at the initiation of ondansetron augmentation, an end of treatment YBOCS score of ≤ 24 and a CGI-Improvement (CGI-I) score of ≤ 2. Upon completion of treatment course patients were followed for 4 weeks.

RESULTS

At week 12, twelve of the 21 (57%) patients were responders. The average reduction in the YBOCS score for the overall group was 27.2%. Responders had an average 44% YBOCS score reduction and 76.9% CGI-I reduction. After discontinuation of ondansetron the YBOCS worsened an average of 15.5% in the entire sample and 38.3% in the responder subsample. No clinically meaningful side effects were reported.

CONCLUSION

OCD patients who do not adequately respond to an SRI may benefit from augmentation with a low-dose of ondansetron. This may provide an alternative approach to augmentation with atypical antipsychotic agents, with a more favorable safety profile.

Disgust and fear responding in contamination-based obsessive-compulsive disorder during pictorial exposure

The emotion of disgust has been implicated in the development and maintenance of contamination-based obsessive-compulsive disorder (OCD). In the present study nonclinical participants with high (n=26) and low (n=28) levels of OCD contamination symptoms were exposed to 2 categories of disgust stimuli (blood injury and body waste) across 4 blocks using standardized disgust images. Self-report disgust and fear were recorded, as well as cardiovascular heart rate. In both groups, an initial primary disgust reaction was observed. Self-report disgust and fear, but not heart rate deceleration, was greater in the high symptom group. The high symptom group showed reductions in heart rate deceleration, whereas the low symptom group did not. Significant differences in self-report changes across time were observed between the groups, with fear increasing to a greater extent for high contamination fearful individuals when viewing body waste images. The implications of these findings for theoretical models and clinical treatment of OCD with prominent contamination symptoms are discussed.

Specificity of fear and disgust experienced during traumatic interpersonal victimization in predicting posttraumatic stress and contamination-based obsessive-compulsive symptoms

Emerging evidence has documented comorbidity between posttraumatic stress disorder (PTSD) and obsessive-compulsive disorder (OCD) among individuals with a history of traumatic events. There is growing recognition of the importance of disgust in each of these conditions independently. No study, however, has examined the potential role of disgust in these conditions following traumatic event exposure. The current study examined the unique role of peritraumatic fear, self-focused disgust, and other-focused disgust in predicting posttraumatic stress symptoms and contamination-based OC symptoms among 49 adult women (M(age)=28.37, SD=13.86) with a history of traumatic interpersonal victimization. Results demonstrated that intensity of peritraumatic self-focused disgust was significantly related to contamination-based OC symptoms while peritraumatic fear and other-focused disgust were related to posttraumatic stress symptoms. These results highlight the need for future research aimed at elucidating the nature of the association between disgust experienced during traumatic events and subsequent psychopathology.

The nature, assessment, and treatment of obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is an anxiety disorder that affects between 1% to 2% of individuals and causes considerable impairment and disability. Although > 50% of individuals experience symptom onset in childhood, symptoms can continue to develop throughout adulthood. Accurate and timely assessment of clinical presentation is critical to limit impairment and improve prognosis. Presently, there are 2 empirically supported treatments available for OCD in children and adults, namely cognitive-behavioral therapy and pharmacotherapy with serotonin reuptake inhibitors. This article provides an introduction to the phenomenology, etiology, and clinical course of OCD. Assessment practices used to evaluate symptom severity are described, and evidence-based treatment options are reviewed, with appropriate distinctions drawn between children and adults. Finally, recommendations for assessment and treatment practices for OCD are explicated.