Mindfulness and Emotion Dysregulation across Internalizing Disorders: A trans-diagnostic comparison of MDD, OCD, and comorbidity

Context and relevance. Emotion regulation and mindfulness are trans-diagnostic mechanisms underlying internalizing disorders such as Obsessive-Compulsive Disorder (OCD) and Major Depressive Disorder (MDD), having a significant influence on symptoms intensity and therapeutic effectiveness. Given the biological and phenomenological intersections as well as the high comorbidity between OCD and MDD, along with the rising number of such cases in Iran, a comprehensive understanding of the aspects of mindfulness and emotion regulation in these populations is essential. Objective. The present study focused on comparing mean scores of emotion regulation and mindfulness dimensions among four groups: Major Depressive Disorder (MDD), Obsessive-Compulsive Disorder (OCD), OCD patients who developed symptoms of depression (Comorbidity of OCD and MDD), and healthy controls. A total of 419 participants, including 101 individuals diagnosed with MDD, 36 individuals diagnosed with OCD, 150 individuals diagnosed with OCD who subsequently developed depressive symptoms (comorbidity), and 132 healthy controls were selected. Hypothesis. The combination of OCD and MDD was predicted to cause more difficulties in managing emotions and being mindful. Methods and materials. Participants were evaluated using the Beck Depression Inventory – Second Edition (BDI-II), the Yale-Brown Obsessive-Compulsive Scale, the Difficulties in Emotion Regulation Scale (DERS), and the Five Facet Mindfulness Questionnaire (FFMQ). Results. The results of the analysis of covariance indicated that the comorbidity group reported more severe impairments in both emotion regulation and mindfulness components in comparison to the three other groups. Moreover, individuals with an OCD diagnosis demonstrated better outcomes in the components of mindfulness and emotion regulation than the MDD group except for non-reactivity on which individuals with MDD performed better. The control group reported higher scores in all components. Conclusions. The combination of OCD and MDD was predicted to cause more difficulties in managing emotions and being mindful.

Introduction

Emotion regulation (ER), as a fundamental process in mental health, is defined as an individual’s capability to regulate emotional experiences and their triggering situations (Gross, 2013).

By focusing on the multidimensional model of emotion regulation (Gratz & Roemer, 2004), regulating emotions may be expressed through different regulatory processes which include the following: inhibition of emotional acceptance (non-acceptance), deficits in executing goal-directed behaviors under distress (goals), challenges in managing impulsive reactions (impulse), restricted access to effective emotion regulation strategies (strategy), impaired emotional awareness (awareness), reduced clarity in emotional response (clarity).

Studies reveal that individuals with various psychological disorders, such as anxiety, obsessive-compulsive disorder, and depression, exhibit deficits in emotion regulation (Santana et al., 2013).

According to Gross’s model, individuals regulate their emotions across five separate stages throughout the timeline of emotional reactions: choosing situations, changing the situation, directing attention, modifying cognition, and controlling reaction. The study demonstrates that these stages correspond to three categories recognized by Aday et al. (2017), which are as follows: 1) deliberate distraction of situations which may elicit some emotions (“attention control”), 2) establishing a different intellectual approach to the problematic issues (“cognitive reappraisal”), 3) modifying behavioral expressions of emotions (“response modulation”).

Expanding on this issue, the study illustrates that people use nine cognitive strategies to regulate their emotions, including self-blame, blaming others, rumination, catastrophizing, perspective taking, positive refocus, positive reappraisal, focus on planning, and acceptance (Ochsner & Gross, 2008). The selection of these strategies is driven by the intensity and valence of emotions, as well as interindividual differences (Kozubal et al., 2023).

Research suggests that adaptive emotion regulation involves skills such as mindfulness and emotional acceptance. Mindfulness, which is defined as paying attention to the present moment without judging the experiences (Karyadi et al., 2014), has been proposed as a cognitive strategy in emotion regulation that can be an alternative to cognitive reappraisal (Opialla et al., 2015). Using factor analysis, Baer et al. (2008) recognized five core facets that define mindfulness. These facets include attentive monitoring of both internal and external stimuli (observe), putting our experiences into words that fall within conscious awareness (describe), intentionally focusing on what we are doing instead of just reacting on autopilot (act mindfully), avoiding judgment of our recent experiences (non-judging), and not reacting immediately to the feelings that arise (non-reacting).

There is an association between mindfulness and enhanced emotion differentiation, greater emotional stability, and improved emotional adjustment (Hill & Updegraff, 2012).

Conversely, inability or poor ability in skills that regulate emotions is a powerful predictor of longer treatment duration and greater dysfunction in daily life in a variety of disorders such as OCD (Bierens et al., 2023). Studies indicate the beneficial effect of mindfulness on mental health (González-Martín et al., 2023; Bice et al., 2014).

Enkema et al. (2020) show an inverse correlation with psychological disorders including anxiety and depression. In general, emotion dysregulation and diminished mindfulness have been reported in both internalizing and externalizing disorders, underscoring the significance of considering them as trans-diagnostic processes; reactions vary across disorders, with more anger and impulsive behaviors in externalizing, and less impulsivity but greater sadness in internalizing disorders (Eisenberg et al., 2001).

To date, however, it is less clear how deficits in emotion regulation and mindfulness vary across different forms of internalizing disorders, including Obsessive-Compulsive Disorder (OCD), Major Depressive Disorder (MDD), and comorbidity of OCD and MDD.

The characteristic of OCD is unpleasant thoughts, rumination, and repetitive behaviors to ease anxiety. In contrast, MDD is prolonged depressed mood and anhedonia (Moini et al., 2021). They even share different brain areas involved in cognitive activities. OCD displays elevated activity in putamen, anterior cingulate and insula while MDD shows decreased activity in inferior parietal cortex and precuneus (Remijnse et al., 2013).

Considering emotion dysregulation, research has indicated that patients with OCD show more impairment in strategy, non-acceptance, impulse control, and clarity (Onur et al., 2021). As addressed in the research of Khosravani et al. (2021), acceptance deficit is a strong predictor of OCD symptoms such as obsession and checking. In comparing MDD and OCD, disrupted impulse control and restricted strategy access play an essential role in distinguishing these disorders in clinical conditions (Whitehead & Suveg, 2016).

Research on trait mindfulness has shown that it is negatively related to depression and obsessive-compulsive disorder (Barnhofer et al., 2011; Wong et al., 2011; Way et al., 2010). For example, higher levels of mindfulness were associated with lower levels of rumination, avoidance, perfectionism, and maladaptive self-control (Blanke et al., 2020; Williams, 2008). However, according to research, mindfulness-based cognitive therapy (MBCT) led to a noticeable decrease in obsessive-compulsive symptoms and depressive symptoms (Başkaya et al., 2021; Fiddaroini et al., 2020). Overall, our knowledge of this matter is limited.

Despite the differences raised in the previous section, there is a dramatic increase in studying the context of comorbidity of OCD and MDD (Sharma et al., 2021). A study shows that 33% of OCD patients experience depressive symptoms (Overbeek et al., 2002), and because of their genetic (Murphy et al., 2013) and origin overlap (Rowe et al., 2022) and due to the impact of comorbidity on treatment procedure (Rowe et al., 2022), assessment of comorbidity is essential and recommended.

Building on this point and the growing population of people suffering from OCD with depressive features in Iran, it is helpful to consider the study of Ghassemzadeh et al. (2017) which was conducted in Roozbeh Psychiatry Hospital and demonstrated that 82% of OCD outpatients who refer to the hospital have depressive symptoms.

The majority of research on individuals with MDD or OCD, which examines emotion regulation – guided by Gross’s model – and mindfulness as key factors in the psychophysiology of emotional disorders, has been conducted separately. However, there is a scarcity of studies directly investigating how specific components of emotion regulation and mindfulness function in individuals with comorbid OCD and MDD. The lack of sufficient research in this area emphasizes the necessity to systematically examine how emotion regulation and mindfulness influence individuals experiencing comorbidity of OCD and MDD.

Moreover, there has been a limited number of studies comparing OCD, MDD, comorbidity of OCD and MDD, and control groups with regard to emotion regulation (as presented in Gross’s model) and facets of mindfulness. This indicates the importance of examining this issue in future studies.

This study mainly aims to evaluate and compare emotion regulation and mindfulness among Iranian adults across four groups: MDD, OCD, comorbidity of OCD and MDD, and a healthy control group.

Furthermore, addressing this gap is essential for enhancing our knowledge of trans-diagnostic processes and implementing more precise interventions for clinical settings.

Materials and methods

Participants

The current study was conducted at Roozbeh Psychiatry Hospital in Tehran during the period from 2016 to 2019. A total number of 419 participants were selected, including 36 patients with OCD, 101 patients with MDD, and 150 OCD patients who developed symptoms of depression (comorbidity of OCD and MDD) all meeting the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (American Psychiatric Association, 2013) and 132 healthy controls who were chosen from hospital staff, students and patient companions. Since the study aimed to evaluate mindfulness and emotion regulation, participants were instructed to complete the standardized instruments corresponding to these constructs.

Participants were included if they met the following criteria: 1) aged 18 years or older, 2) diagnosed with OCD, MDD, and OCD with comorbid depressive symptoms, 3) with a minimum of eight years of educational background, 4) willing to provide informed consent for participation in the study. Individuals with a history of substance abuse, psychotic illness, or bipolar spectrum disorder were excluded from the study.

Table 1 summarizes the demographic characteristics of the sample. As indicated, the mean (SD) age of the sample was 32.48 (9.90) years (ranging from 18 to 72 years). A high percentage of the participants were female (69.9%) and married (57.7%), with a bachelor’s degree (39.4%).

Instruments

BDI-II: Beck Depression Inventory-Second Edition

Measurement of depression was performed using the Beck Depression Inventory-Second Edition (BDI-II) which is a 21-item standardized scale designed to evaluate depression in adolescents and adults. Every item has a score ranging between 0 to 3 on a 4-point Likert scale. Minimum scores are 0-13, mild scores are 14-19, moderate scores are 20-28, and severe scores are 29-63 (Arnarson et al., 2008). Studies have confirmed that the scale is valid (Cronbach’s alpha=0.89) instrument for measuring depression (Magán et al., 2008). The Persian version of BDI-II has also shown strong internal consistency, with a Cronbach’s alpha of 0.87 (Ghassemzadeh et al., 2005).

Y-BOCS: Yale-Brown Obsessive Compulsive Scale

This semi-structured interview is used to assess how severe Obsessive-Compulsive Disorder (OCD) symptoms are, measuring the current severity of obsessions through ten rating options. Five dimensions are evaluated by the scale: 1) how much time is spent, 2) how much it interferes with daily life, 3) how distressing it is, 4) how much the person resists the thoughts, and 5) how much control they feel they have. It separately measures symptoms of obsessive thoughts and compulsive behaviors. The scale demonstrates excellent inter-rater reliability (r = 0.98) and strong internal consistency (r = 0.84). Test-retest reliability over a two-week period has also been confirmed (r= 0.84) (Asadi et al., 2016). Answers are given on a 5-point scale from 0 to 4, with total scores interpreted as follows: 0–9 indicates minimal severity, 10–15 indicates mild severity, 16–25 indicates moderate severity, and 26–40 indicates severe symptoms (Rajezi Esfahani et al., 2012).

Difficulties in Emotion Regulation Scale (DERS)

Gratz and Roemer (2004) developed a 36-item scale designed to assess six key subscales: non-acceptance (e.g., "When I’m upset, I feel guilty for feeling that way"), goals (e.g., "When I’m upset, I have difficulty getting work done"), impulse (e.g., "When I’m upset, I lose control over my behaviors"), awareness (e.g., "When I’m upset, I acknowledge my emotions"), strategies (e.g., "When I’m upset, my emotions feel overwhelming"), and clarity (e.g., "I am confused about how I feel"). Together, these subscales account for 55.68% of the total variance. The scale demonstrated excellent internal consistency, with a Cronbach’s alpha of 0.93.

The Persian version was adapted using the back-translation method. Its reliability was confirmed through a two-week test-retest study involving 30 students, resulting in a reliability coefficient of 0.85 and a Cronbach’s alpha of 0.91 (Seyed Hashemi et al., 2018).

Five Facet Mindfulness Questionnaire (FFMQ)

In 2006, Baer, Smith, Hopkins, Krietemeyer, and Toney formulated a 39-item self-report questionnaire aimed at measuring five specific dimensions of mindfulness: observe (e.g., "While walking, I am aware of the sensations in my body"), describe (e.g., "I can describe my feelings well"), act mindfully (e.g., "I criticize myself for having irrational emotions and thoughts"), non-judgment of internal experiences (e.g., "I can perceive emotions without reacting to them"), and non-reacting automatically to inner feelings (e.g., "I am easily distracted"). The internal consistency of the scale was confirmed by a Cronbach’s alpha of 0.90, indicating high reliability (Ghorbani et al., 2014).

The five-factor model of the FFMQ was supported by Khanjani et al. (2022) with fit indices indicating an acceptable model fit: RMSEA = 0.06, CFI = 0.81, GFI = 0.91, and NFI = 0.87. The FFMQ scores were negatively correlated with measures such as the Difficulties in Emotion Regulation Scale (DERS), trait anxiety, affect control, and the suppression subscale of the Emotion Regulation Questionnaire (ERQ), while a positive correlation was found with the reappraisal subscale of the ERQ. The Cronbach’s alpha for the FFMQ in this study was reported as 0.78.

Procedures

Participants from all four groups (OCD, MDD, comorbidity of OCD and MDD, and a healthy control group) were selected from Roozbeh Psychiatric Hospital in Tehran. Following approval from a university-based ethics committee, data were collected from participants individually. Initially, 421 cases were selected based on the predefined inclusion and exclusion criteria. Patients clinically diagnosed by an expert psychiatrist with the target disorders were screened to confirm eligibility. Two participants were later excluded for failing to meet the criteria, leaving a final sample of 419. Assurance was given to participants that their personal information would remain confidential and their identities protected. They were also informed that participation was voluntary and that they could withdraw at any point.

Statistical analysis

A multivariate analysis of covariance (MANCOVA) was conducted to examine group differences in emotion regulation and mindfulness components, controlling for education level and marital status as potential confounders. Preliminary assumption testing indicated a violation of homogeneity of covariance matrices (Box's M test, p < .001) and heterogeneity of variance for several variables (Impulse, Strategies, Clarity, Acting with Awareness, Non-Reactivity; p < .05). Univariate analyses of covariance (ANCOVAs) were conducted on each dependent variable as follow-up tests. A Bonferroni correction was applied to control for Type I error across the 11 tests, resulting in a significance level set at p < .0045.

Results

To examine baseline differences between diagnostic groups and demographic parameters, preliminary analyses were conducted. The final sample comprised 421 participants. After excluding two cases with missing data on the grouping variable, the study consisted of 419 participants. Participants were classified into four categories: control (n = 132, 31.4%), Major Depressive Disorder (MDD; n = 101, 24.0%), Obsessive-Compulsive Disorder (OCD; n = 36, 8.6%), and a comorbid group with both MDD and OCD (n = 150, 35.6%). The sample was predominantly female (69.6%). Demographic characteristics are presented in Table 1.

Table 1
Demographic Characteristics by Diagnostic Group

Note. MDD = Major Depressive Disorder; OCD = Obsessive-Compulsive Disorder; Comorbid = co-occurring MDD and OCD. Percentages may not sum to 100 due to rounding.

A one-way ANOVA revealed a significant difference in mean age between groups, F (3, 414) = 3.66, *p* = .013. Post hoc comparisons indicated that the MDD group was significantly older than the comorbid group (mean difference = 3.33 years, *p* = .018). No other pairwise comparisons were significant.

Chi-square tests revealed significant group differences in marital status, χ²(6, N = 419) = 13.13, *p* = .041, with the comorbid group having a higher proportion of single individuals (50.7%), and education level, χ²(15, N = 419) = 32.45, *p* = .006, with the control group having more bachelor's degrees or higher (63.7%). Gender distribution did not differ significantly, χ²(6, N = 419) = 9.16, *p* = .165

3.2. Primary Analyses

After controlling for covariates, there was a significant multivariate effect of group on the combined dependent variables, Wilks' Λ = .536, F (33, 1182.12) = 8.43, *p* < .001, partial η² = .19, indicating a large effect size. Descriptive statistics are presented in Table 2.

Table 2
Means and Standard Deviations for Dependent Variables by Group

Note. MDD = Major Depressive Disorder; OCD = Obsessive-Compulsive Disorder; Comorbid = co-occurring MDD and OCD.

The results revealed statistically significant main effects of group on nine of the eleven dependent variables after controlling for education and marital status. The strength of these effects ranged from small to large, with partial eta-squared values indicating that group membership explained between 8.7% and 33.6% of the variance in these outcome measures. Table 3 presents the complete ANCOVA results for the group effect, including F-values, degrees of freedom, p-values, effect sizes, and significant pairwise comparisons.

Table 3
ANCOVA Results for Group Differences on Dependent Variables with Pairwise Comparisons

Note. C = Control group; MDD = Major Depressive Disorder group; OCD = Obsessive-Compulsive Disorder group; both = Comorbid group; n.s. = not significant after Bonferroni correction (*p* < .0045). All comparisons significant at *p* < .05 after Bonferroni adjustment. The symbol "<" indicates "significantly lower than."

The pattern of results revealed consistent group differences across multiple dimensions of emotion regulation and mindfulness. The comorbid group demonstrated the most severe impairment, showing significantly greater difficulties than all other groups on most measures of emotion regulation facets (Non-acceptance,Goals,Impulse, Strategies) and the lowest scores in mindfulness components (Describing, Non-Reactivity, Acting with Awareness, Non-judging). The control group consistently showed the most adaptive functioning across all measures, performing significantly better than all clinical groups on the majority of variables.

Notably, the OCD and MDD groups typically occupied an intermediate position, often differing significantly from both the control and comorbid groups. However, they rarely differed from each other, suggesting similar levels of impairment in these specific domains. The variables Awareness and Observing did not show significant group differences after multiple comparison correction, indicating that these particular mindfulness components may be less affected by the diagnostic categories examined in this study.

Effect sizes ranged from small to large, with the largest effects observed for Strategies (access to emotion regulation strategies), Acting with Awareness, and Goals (goal-directed behavior), indicating that these domains are particularly sensitive to diagnostic differences. These findings suggest that emotion regulation difficulties and mindfulness deficits are most pronounced in comorbid cases and reflect a dimensional pattern of impairment across diagnostic categories.

Discussion

The current study investigated mindfulness and emotion regulation and their clinical correlates within a sample of individuals with OCD, MDD, comorbidity of OCD and MDD, and a healthy control group. As anticipated, the results show that emotion regulation components and mindfulness facets significantly differ between the healthy control group and the three clinical groups, and when analyzing the clinical groups separately, the comorbid group generally demonstrates the most severe condition.

When we considered the emotion regulation domain, we found that clinical populations relative to the healthy control group, exhibit marked deficits in components such as non-acceptance, impulse control, and goal-directed behaviors in stressful conditions. This is consistent with the results of Gratz and Roemer (Gratz & Roemer, 2004) that indicate these deficits are not confined exclusively to a particular disorder but instead act as a trans-diagnostic mechanism underlying internalizing disorder. Through a comparative evaluation of MDD and OCD across the components of emotion regulation, such as control over impulsive behaviors, goal-directed behaviors, non-acceptance, awareness, and clarity, no notable differences were found between groups, although the MDD group demonstrated slightly greater impairment. However, in the strategy component, a significant difference was found. This can be explained by the important role of rumination in the difference. Some studies that have led to this result show that rumination and depression have been linked to executive functions, especially deficits in inhibitory functions (Joormann & Stanton, 2016). On the other hand, dysfunction of inhibition may be associated with difficulties in ignoring novel aspects of situations and lower cognitive reappraisal as an adaptive strategy in emotion regulation due to impaired working memory capacity (Thompson et al., 2015). This may explain why patients with MDD have more limited access to emotion regulation strategies than patients with OCD.

Individuals diagnosed with both OCD and MDD exhibited more pronounced difficulties in emotional regulation in comparison to those affected by a single disorder, which consequently increases their vulnerability. In the emotional non-acceptance component, the findings indicated that the group of patients with comorbidity showed the lowest tendency to accept their emotions relative to the control group. This could indicate an intensified reaction to emotions and more problems in managing internal states. Patients with MDD also showed greater impairment than the healthy control group on this component. This finding could indicate that people in this group have a greater tendency to resist negative thoughts and emotions, a reaction that is often accompanied by symptoms such as rumination and feelings of deep sadness and hopelessness. Greater impulsivity in MDD and comorbidity by some findings (Joormann & Stanton, 2016; LeMoult et al., 2016) that showed depressed patients have more difficulty in cognitive control and inhibition of processing negative thoughts and reduced cognitive inhibitions are associated with more rumination as a risk factor in depression (Demeyer et al., 2012). Although, the result of Hasegawa et al. (Hasegawa et al., 2021) showed no significant relationship between impulsive action and depression, but stressors and rumination mediated the relationship between impulsivity and depression. This finding indicates that the simultaneous presence of two disorders not only exacerbates the symptoms of each disorder alone, but also creates deeper disturbances in the emotion regulation component (Whitehead & Suveg, 2016).

Upon addressing the facets of mindfulness, findings indicate that the comorbidity and the MDD group had lower scores in the observing facet than the OCD and the control group.The observation component describes an individual’s ability to register sensory and cognitive experiences without interference, thereby reflecting their capacity to remain present in the moment (Baer et al., 2008). Since difficulty concentrating (American Psychiatric Association, 2013) and cognitive impairments such as rumination are well-known symptoms of depression, it is understandable that individuals with this disorder tend to exhibit lower scores in this domain. Moreover, in the comorbid group-consisting of people who originally had OCD and later developed depressive symptoms-the lower scores can be explained along the same lines. Therefore, mindfulness-based interventions for both depressed and comorbid populations can be effective by focusing on restoring the observation through reducing rumination and enhancing engagement with the environment.

In this part, our intention is to explore the describing facet as an individual’s capacity to conceptualize and express emotions (Baer et al., 2008). Our results are in agreement with earlier studies in this area. Based on previous studies, describing is linked to alexithymia characterized by a diminished capacity to recognize and distinguish one’s own emotions and those of others (Nowakowski et al., 2013). Depressed patients often struggle with challenges associated with alexithymia (Dalbudak et al., 2014). Additionally, according to Khosravani et al. (Khosravani et al., 2021), OCD patients experience difficulties with alexithymia, except in the subscale of describing emotions. This finding could explain lower scores of the MDD group on the describing in contrast to the OCD and the control group. The approximately equal scores between the MDD and the comorbidity groups suggest that, although OCD patients maintain their baseline functioning, the addition of depressive symptoms exacerbates impairment in the describing component. This insight underscores the importance of enhancing skills in identifying and describing emotions in mindfulness-based interventions for MDD and comorbidity patients.

The findings of the current study demonstrated significant differences in scores of acting with awareness which is consciously focusing on your activity in the present moment in clinical populations relative to the control group. A comparison between MDD and OCD indicated lower scores in the MDD group in the component of acting with awareness which is in line with the study of Didonna (Didonna et al., 2019), showing that OCD patients have significantly higher scores on this component compared to MDD. This difference likely arises from the fundamental emotional and cognitive differences between these two disorders. The greater difficulties in acting with awareness observed in patients with MDD as compared to those with OCD can be attributed to issues such as reduced attention, rumination, and diminished motivation. While patients with OCD also struggle with intrusive thoughts, their compulsive behaviors tend to be intentional and goal-oriented (Gillan et al., 2011). In the comorbidity group, the interplay between compulsive and repetitive behaviors on the one hand and diminished motivation on the other acts in a mutually reinforcing way, and may be responsible for the most severe deficits observed in acting with awareness scores. According to these findings, targeting this component in treatment of OCD, MDD, and comorbidity of them can be beneficial in reduction of psychological symptoms and predicting impairments in patient’s daily functioning.

In accordance with our original hypothesis and existing literature (Gross, 2014), the cross-group comparison indicated that patients with OCD, MDD, and comorbidity scored significantly lower on the non-judging facet than the healthy control group.

As suggested in a prevalent theory, the component of non-judgment inversely is linked to dysfunctional cognitive appraisals, which are shared in MDD and OCD (Raphiphatthana et al., 2016; Abramowitz & Jacoby, 2014). In MDD, maladaptive cognitive processes often lead to persistent sadness and negative interpretation of internal experiences. In contrast, OCD patients tend to interpret their intrusive thoughts as threatening (Calkins et al., 2013). The coexistence of OCD and MDD may result in more severe and complex difficulties in the comorbid group; accordingly, lower scores on this facet may be expected.Regarding the non-reactivity facet, the findings of present research showed impairments in the clinical groups compared to the control group. By considering OCD and MDD, in contrast to previous components, a lower score was observed for OCD in this domain. Given that non-reactivity is defined as the ability to allow thoughts and emotions to come and go without interference or compulsive engagement (Baer et al., 2008), whereas obsessive thoughts are a diagnostic criterion for OCD (American Psychiatric Association, 2013), this decrease appears logical. Individuals with OCD react to these intrusive obsessions by performing rituals or avoidance, demonstrating low non-reactivity. In MDD, the underlying reason may involve being caught in a trap of negative thoughts (Nolen-Hoeksema et al., 2008), which are less destructive than obsessive thoughts. In the comorbidity group, the interaction between these two factors-namely compulsive responses from the one hand and being trapped in a cycle of rumination and negative thinking- lead to more severe impairment. Mindfulness-based interventions, especially for individuals experiencing comorbidity of OCD and MDD, have the potential to enhance clinical outcomes by cultivating a non-judgmental engagement from intrusive thoughts.

Conclusions

In summary, the findings of the current study show distinct differences between OCD and MDD in emotional regulation and mindfulness. While these differences may not be highly pronounced, their co-occurrence is often associated with a heightened impairment in these domains. Our results underscore the significance of investigating emotion regulation and mindfulness among individuals with OCD, MDD, and comorbidity of them in order to validate and improve interventional and theoretical models.

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