Quality of life in obsessive-compulsive disorder: The role of mediating variables

Psychiatry Research 206 (2013) 43–49

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Quality of life in obsessive-compulsive disorder: The role of mediating variables Brittany B. Kugler a,b, Adam B. Lewin b,c, Vicky Phares a, Gary R. Geffken d, Tanya K. Murphy b,c, Eric A. Storch a,b,c,n a

Department of Psychology, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL 33620, USA Department of Pediatrics, University of South Florida, 800 6th Street South, Box 7523, St. Petersburg, FL 33701, USA c Department of Psychiatry and Behavioral Neuroscience, University of South Florida, 800 6th Street South, Box 7523, St. Petersburg, FL 33701, USA d Department of Psychiatry, University of Florida, 100 S. Newell Drive L4100, Gainesville, FL 32611, USA b

a r t i c l e i n f o

abstract

Article history: Received 3 April 2012 Received in revised form 3 October 2012 Accepted 10 October 2012

This study examined the association of various clinical features of obsessive-compulsive disorder (OCD) with quality of life (QoL) in 102 adults with a principal diagnosis of OCD. Participants were assessed by trained clinicians using the Anxiety Disorders Interview Schedule 4th edition, the Yale-Brown Obsessive-Compulsive Scale, and an unstructured clinical interview. Subjects completed the MOS-36 Item Short Form Health Survey, and Beck Depression Inventory-II. Obsessive-compulsive symptom severity was negatively correlated with emotional health, social functioning and general health QoL. Depressive symptoms mediated the relationship between obsessive-compulsive symptom severity and emotional health, social functioning and general health QoL. Additionally, interference of obsessivecompulsive symptoms mediated the relationship between obsessive-compulsive symptom severity and emotional health, social functioning and general health QoL. Resistance against obsessive-compulsive symptoms mediated the relationship between obsessive-compulsive symptom severity and social functioning QoL. Diminished QoL is present in persons with OCD and is essential in understanding the complete clinical picture of OCD. & 2012 Elsevier Ireland Ltd. All rights reserved.

Keywords: Quality of life Obsessive-compulsive disorder Treatment Assessment Depression Anxiety

1. Introduction Obsessive-compulsive disorder (OCD) is an anxiety disorder affecting approximately 1% of adults (Crino et al., 2005) that is characterized by the presence of intrusive thoughts, impulses or images (obsessions) and/or repetitive behaviors, rituals or mental acts (compulsions) that cause significant distress or interference with daily functioning (American Psychiatric Association, 2000). When left untreated, OCD runs a chronic and debilitating course often contributing to interpersonal and psychological difficulties (Norberg et al., 2008). Comorbidity is common in those with OCD with approximately 70% of patients having a comorbid condition, most frequently depressive disorders or another anxiety disorder (Rasmussen, 1994; Storch et al., 2010). Obsessive-compulsive disorder has been associated with considerable functional impairment with the World Health Organization reporting that OCD accounts for 2.5% of global years lost due to disability (Ayuso-Mateos, 2000). Given the high rates of n Corresponding author at: Department of Pediatrics, University of South Florida, 800 6th Street South, Box 7523, St. Petersburg, FL 33701, USA. Tel.: þ1 727 767 8230. E-mail address: [email protected] (E.A. Storch).

0165-1781/$ - see front matter & 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.psychres.2012.10.006

disability and impairment associated with OCD and comorbid conditions, it is not surprising that quality of life (QoL) is negatively affected. Quality of life is a broad construct often defined by two primary components: an individual’s functional status and an individual’s subjective determination of how their health impacts their life (Rapaport et al., 2005). Notably, measures of QoL generally depend on self-report and therefore estimates of functional status are also a function of the individual’s subjective experience of impairment. For the purposes of this study, QoL is defined as encompassing four domains including physical health, emotional health, social functioning, and general health QoL. The physical health domain measures role limitations due to physical health problems, and includes the following components: role-physical, physical functioning and bodily pain. The emotional health domain measures role limitation due to emotional problems and includes the following components: role-emotional and mental health. The social domain includes a measure of social functioning as it is affected by overall physical and mental health. The general health QoL domain includes the following components: general health and vitality/energy (Ware et al., 1993). Diminished QoL has been well documented across a broad range of anxiety disorders (Barrera and Norton, 2009; Lunney and

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B.B. Kugler et al. / Psychiatry Research 206 (2013) 43–49

Interference of Symptoms or Resistance to Symptoms (YBOCS); Depression Severity (BDI-II) a

CGI-Severity--- OCD

b

MOS Quality of Life domain (Physical, Emotional, Social, General)

c’

Fig. 1. Mediational model of OCD severity and quality of life.

Schnurr, 2007; Mendlowicz and Stein, 2000), affective disorders (Barrera and Norton, 2009; Bobes et al., 2001; Huppert et al., 2009) and schizophrenia (Meijer et al., 2009; Tomida et al., 2010). Meta-analytic findings showed proportions of persons with impaired QoL as follows: major depressive disorder (63%), dysthymia (56%), panic disorder (20%), OCD (26%), social phobia (21%), and posttraumatic stress disorder (56%) (Rapaport et al., 2005). When addressing QoL in persons with OCD, studies have shown QoL to be comparable (Bobes et al., 2001) or worse than adults with schizophrenia (Stengler-Wenzke et al., 2007) and significantly worse than depressed patients (Bobes et al., 2001). Research addressing predictors of QoL in OCD is characterized by mixed results. Studies looking specifically at QoL in OCD have shown that obsessive-compulsive symptom severity and number of obsessivecompulsive symptoms are inversely associated with QoL across all domains including general health, emotional health, social functioning and physical health (Eisen et al., 2006; Masellis et al., 2003; Moritz et al., 2005). Some have found that QoL impairment is more highly associated with obsession severity than compulsion severity (Eisen et al., 2006), whereas others have found the opposite (Moritz et al., 2005). Resistance against and control of symptoms has uniquely predicted functional impairment in adults with OCD. Specifically, functioning is greatly impaired when little effort is made to resist and control obsessive-compulsive symptoms (Storch et al., 2009). However, the role of symptom interference and resistance has yet to be examined as possible mediating variables in the relationship between OCD severity and QoL. Understanding the role of interference of symptoms and resistance against symptoms in the relationship between OCD and QoL may help generate better targeted treatments for improving QoL in persons with OCD. For example, motivational components may be incorporated in treatment for those exhibiting limited resistance against symptoms (Simpson et al., 2008). Alternatively, for those who display marked interference, treatment may dually focus on reducing symptom interference while simultaneously re-engaging the person in appropriate work and social tasks (Bystritsky et al., 2001). In addition to interference of and resistance against obsessivecompulsive symptoms as a mediator of the relationship between OCD severity and QoL, depressive symptoms may also mediate the relationship between diminished QoL and OCD (Abramowitz et al., 2007; Besiroglu et al., 2007; Fontenelle et al., 2010). Comorbidity of OCD and major depressive disorder (MDD) is related to a significantly diminished QoL and higher functional impairment relative to individuals with OCD without MDD. Those with comorbid OCD and MDD have more severe obsessions, compulsions and depressive symptoms as compared to the OCD-only group (Besiroglu et al., 2007). Thus, it is possible that obsessive-compulsive symptom severity contributes to increased depressive symptoms due to withdrawal from positive activities as well as distress related to symptoms, thereby contributing to diminished QoL across domains.

The present study examines theoretically relevant clinical correlates of QoL in adults with OCD. We had four specific research aims. First, we compared QoL in adults with OCD relative to other psychiatric conditions, including MDD, panic disorder and schizophrenia. In accordance with previous findings, we hypothesized that emotional health, social functioning and general health QoL in persons with OCD would be more diminished than these domains of QoL in persons with MDD, panic disorder and schizophrenia. Second, we investigated the relationship between obsessive-compulsive symptom severity with four QoL domains (general health, emotional health, social functioning and physical health). It was predicted that, consistent with prior research, obsessive-compulsive symptom severity will correlate inversely with QoL for emotional health, social functioning and general health domains, yet will not be significantly associated with physical health QoL (Eisen et al., 2006; Masellis et al., 2003; Moritz et al., 2005; Rapaport et al., 2005). Third, we investigated the role of depressive symptom severity as a mediator in the relationship between OCD severity and QoL. It was expected that depressive symptoms would mediate this relationship across the domains of emotional health, social functioning and general health QoL (based on past research (Moritz et al., 2005), no significant relationship was expected between OCD severity and physical health QoL). Lastly, we tested whether symptom interference and resistance against symptoms mediated the relationship between obsessive-compulsive symptom severity and QoL (Fig. 1). These models allowed for the examination of two related theories regarding the association between obsessive-compulsive symptom severity and diminished QoL. First, we believed that obsessive-compulsive symptom severity would be related to symptom interference, which would mediate the relationship between obsessive-compulsive symptom severity and diminished QoL. This finding would adhere to the theory that symptom interference is related to a reduction of role capabilities and engagement in routine activities which is thereby associated with diminished QoL. Second, we believed that resistance against symptoms would serve as a buffering factor in maintaining QoL. Similar to our understanding of the role of symptom interference, this finding would indicate that resistance against symptoms and control would be directly associated with role limitations and participation in routine and pleasurable activities, which is ultimately related to diminished QoL.

2. Method 2.1. Participants Participants included 102 adults with a principal diagnosis of OCD according to the Diagnostic and Statistical Manual of Mental Disorder—Fourth Edition—Text Revision (DSM-IV-TR; American Psychiatric Association, 2000). Participants were referred to a university based specialty clinic for cognitive-behavioral treatment. Written consent was received by all persons choosing to be screened for possible participation in larger studies on CBT outcome (Storch et al., 2007, 2008).

B.B. Kugler et al. / Psychiatry Research 206 (2013) 43–49 Participants ranged in age from 18 to 79 years old (M ¼29.4, S.D. 7 10.9 years) with 48% female (N ¼49). The ethnic distribution was Caucasian (96.3%), African American (1.9%), Asian (0.9%), and other (9%). Obsessive-compulsive disorder diagnoses as well as comorbid diagnoses were made by experienced clinical psychologists through an unstructured interview and verified with the Anxiety Disorder Interview Schedule-4th edition (ADIS-IV) (Brown et al., 1994). Clinicians were trained by first observing at least five administrations of the ADIS-IV and Y-BOCS and then administering the measures under direct supervision. Seventy-three percent had diagnosed comorbid conditions, most commonly generalized anxiety disorder (n¼39), major depressive disorder (n ¼37), and/or social phobia (n¼32). 2.2. Measures Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV). The ADIS-IV (Brown et al., 1994) is a semi-structured clinical interview based on DSM-IV diagnostic criteria that assesses the presence of anxiety disorders and allows for functional analysis of the anxiety disorders. The ADIS-IV also provides sections that allow for the assessment of commonly comorbid disorders including mood, somatoform and substance use disorders. The ADIS-IV adheres to the multiaxial system of the DSM-IV and is commonly used in research addressing anxiety and related disorders (Brown et al., 1994). Yale-Brown Obsessive Compulsive Scale (Y-BOCS). The Y-BOCS (Goodman et al., 1989a, 1989b) is a 10-item semi-structured clinician administered measure of obsession and compulsion severity. Each item addresses self-reported experiences in the last week. Questions are rated on a five-point Likert scale ranging from 0 to 4, with higher scores representing greater symptom severity. Items 1–10 (excluding items 1b and 6b) are used to determine a total severity score. Interference is defined as the sum of items one, two, three and six, seven, eight on the Y-BOCS (Goodman et al., 1989a, 1989b). These items address time occupied by obsessions/ compulsions, interference of obsessions/compulsions with activities, and distress over obsessions/compulsions. Resistance is defined as items four, five and nine, 10, which address efforts made to resist obsessions/compulsions and degree of perceived control over obsessions/compulsions (Goodman et al., 1989a, 1989b). Satisfactory psychometric properties for the Y-BOCS have been found, including internal consistency, construct validity, and treatment sensitivity (Deacon and Abramowitz, 2005; Goodman et al., 1989a, 1989b). RAND MOS-36 Item Short Form Health Survey (MOS-36). The MOS-36 (Ware et al., 1993) consists of 36 items that assess domains of physical health, emotional health, social functioning and general quality of life. The scale is comprised of measures assessing eight different components of health including: physical functioning (e.g., does your health limit you in completing moderately physical activities such as vacuuming?), physical role functioning (e.g., have you had any problems with your work or other regular daily activities as a result of your physical health?), emotional role functioning (e.g., have you had any problems with your work or other regular daily activities as a result of your emotional health?), perceptions of general health (e.g., rating of overall general health), emotional health (e.g., have you been a very nervous person, have you been a happy person?), vitality/energy (e.g., did you feel full of pep?), bodily pain (e.g., how much did pain interfere with your normal work?), and social functioning (e.g., how much of the time has your physical or emotional problems interfered with social activities, like visiting friends?) (Hays and Morales, 2001; Hays et al., 1993). Low scores on the MOS-36 indicate impaired QoL, while higher scores indicate better QoL. The MOS-36 has shown good reliability and validity over diverse populations (McHorney et al., 1993; Ware et al., 1993). Beck Depression Inventory-Second Edition (BDI-II). The BDI-II (Beck et al., 1996) is a 21-question, self-report inventory of depressive symptoms experienced during the past week. Questions are rated on a four-point Likert scale ranging from 0 to 3, with higher scores representing greater symptom severity. Extensive reliability and validity data have been reported in clinical and non-clinical samples (Beck et al., 1996; Storch et al., 2004; Whisman et al., 2000). Clinical Global Impression-Severity Scale (CGI-Severity). The CGI-Severity (National-Institute-of-Mental-Health, 1985) is a clinician rating scale of illness severity, ranging from 0 (‘no illness’) to 6 (‘severe illness’). The CGI-Severity is a frequently utilized measure with high treatment sensitivity (Lewin et al., 2011; Sousa et al., 2006). 2.3. Data analysis To investigate the hypothesis concerning the comparability of QoL across conditions, one-sample t-tests were used to compare the eight different components of health including: physical functioning, physical role functioning, emotional role functioning, perceptions of general health, emotional health, energy/ lethargy, bodily pain, and social functioning in OCD to historical means for QoL in primary panic disorder, major depressive disorder and schizophrenia. The depression sample was a ‘‘pure’’ sample with no known comorbidities, while psychopathological comorbidities were not assessed in the sample of persons with primary diagnoses of schizophrenia. Persons with panic disorder did not have comorbid major depressive disorder or social anxiety disorder, however, other

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psychopathological conditions were not evaluated. Historical data from adults with panic disorder was taken from a study addressing QoL scores on the MOS-36 (N¼ 33) (Simon et al., 2002). Data from adults with major depressive disorder was taken from a study addressing QoL on the MOS-36 (N ¼54) (Schonfeld et al., 1997). Lastly data from adults with schizophrenia (N ¼137) was taken from a study looking at QoL on the MOS-36 (Sciolla et al., 2003). Correlations were used to investigate the hypothesis that symptom severity on the Y-BOCS is inversely related to QoL scores on the MOS-36. For all analyses, a p-value of less than 0.05 was used for significance testing. Mediational analyses addressed whether symptom interference or resistance against symptoms as measured on the Y-BOCS or depressive symptoms as measured by the BDI-II mediated the relationship between obsessive-compulsive illness severity (CGI-Severity) and QoL across three domains of emotional health, social functioning and general QoL. Using the bootstrapping mediation method, the provided sample was resampled k¼ 5000 times generating a 95% confidence interval. The criterion for mediation was the exclusion of zero between the lower and upper bound of the confidence interval. If zero was not present it suggested that the indirect effect of the mediator on the outcome was not zero with 95% confidence (Hayes, 2009) implying full mediation. A bootstrap estimate of the mediating effect was computed using the SPSS macro INDIRECT (Preacher and Hayes, 2008)

3. Results 3.1. Sample characteristics Zero-order correlations highlighted a significant negative relationship between age and both emotional health (r ¼  0.34, po0.01) and social functioning (r¼  0.35, po0.01) QoL. Correlations between age and physical health QoL (r¼  0.21, p ¼0.05), general health QoL (r ¼  0.18, p ¼0.11), Y-BOCS severity score (r ¼0.18, p ¼0.09), and CGI-Severity rating (r ¼0.13, p ¼0.21) were non-significant. Independent group t-tests indicated a significant gender difference on emotional health QoL (t(100)¼  2.07, po0.05) with females experiencing significantly more diminished emotional health QoL than males. No further differences were noted on any other domain of QoL, symptom severity on the Y-BOCS, or CGI-Severity rating for age, gender or ethnicity. Comorbidity with OCD was related to significantly more diminished emotional health (t(100) ¼3.02, p o0.05), social functioning (t(100) ¼3.02, p o0.05), and general health (t(100) ¼3.88, po0.01) QoL when compared to an OCD only group. Rates of overall comorbidity with OCD did not differ significantly between males and females. One sample t-tests were used to compare scores on the eight components of QoL on the MOS-36 in persons with OCD relative to historical means for QoL in persons with panic disorder, MDD and schizophrenia (Table 1). Social functioning QoL was significantly worse and physical health QoL was significantly better in those with OCD relative to patients with schizophrenia, panic disorder or MDD. Additionally, role emotional QoL and vitality/ energy was worse for those with OCD relative to those with either schizophrenia or panic disorder. Persons with OCD had significantly worse general health than those with panic disorder, but significantly better general health than those with MDD. Mental health QoL did not differ across OCD, panic disorder and MDD; persons with schizophrenia fared better in this domain.

3.2. Associations between QoL, symptom severity and symptom dimensions As predicted, symptom severity on both the Y-BOCS and the CGI-Severity was negatively correlated with emotional health (rs ¼  0.24, 0.25, pso0.05), social functioning (rs¼  0.32,  0.37, ps o0.01) and general health (rs ¼  0.30, 0.25, ps o0.01) QoL domains. There was no significant relationship between obsessive-compulsive symptom severity and physical health QoL.

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Table 1 Quality of life means (MOS-36) across conditions. Group/effect

Reference Group: OCD (N ¼ 102) Schizophrenia (N ¼137) Panic disorder (N¼ 62) MDD (N ¼ 54)

MOS-36 quality of life domains Physical functioning

Rolephysical

Roleemotional

Vitality/ energy

Mental health Social functioning

Bodily pain General health

88.43 65.0nn 79.6nn 82.5n

77.21 54.44nn 54.9nn 55.6nn

33.33 62.5nn 55.5nn 37.4

38.77 54.8nn 51.5nn 35.5

47.1 66.1nn 47.7 48.6

82.6 68.9nn 68.1nn 61.6nn

48.41 68.7nn 61.0nn 60.3nn

64.46 62.8 71.1n 54.9nn

Note: One sample t-tests compare current OCD reference group with other diagnostic groups. n

p o 0.05. p o0.001.

nn

Table 2 Mediators in the relationship between illness severity and QoL. Data include unstandardized coefficient (S.E.). c0 Path

Mediators entered independently

a Path

b Path

c Path

Depression symptoms Physical health QoL Emotional health QoL Social functioning QoL General health QoL

3.44(1.11)n 3.44(1.11)n 3.44(1.11)n 3.44(1.11)n

 1.34(0.69)  3.21(0.40)nn  1.17(0.23)nn  1.73(0.29)nn

 14.32(7.59)  12.76(5.59)n  10.98(2.78)nn  8.27(3.67)n

Interference of symptoms Physical health QoL Emotional health QoL Social functioning QoL General health QoL

2.95(0.30)nn 2.95(0.30)nn 2.95(0.30)nn 2.95(0.30)nn

 0.64(2.43)  3.99(1.76)n  3.08(0.84)nn  3.06(1.14)n

Resistance to symptoms Physical health QoL Emotional health QoL Social functioning QoL General health QoL

1.01(0.27)nn 1.01(0.27)nn 1.01(0.27)nn 1.01(0.27)nn

3.22(2.73) 1.74(2.04) 2.13(0.99)n  0.12(1.33)

n

Indirect effects (coefficient)

95% CI

 9.72(7.85)  1.73(4.54)  6.95(2.59)n  2.33(3.30)

 4.6  11.03  4.03  5.94

 12.39 to 0.04  18.47 to  3.90n  7.11 to -1.62n  11.20 to  2.04n

 12.44(7.32)  14.03(5.43)n  10.89(2.70)nn  9.05(3.54)n

 10.56(10.28)  2.25(7.45)  1.79(3.56)  0.01(4.80)

 1.88  11.79  9.1  9.04

 17.65  21.24  13.50  15.00

 12.44(7.32)  14.03(5.43)n  10.89(2.70)nn  9.05(3.54)n

 15.71(7.82)n  15.80(5.83)n  13.05(2.84)nn  8.93(3.81)n

3.27 1.77 2.16  0.12

 0.97 to 11.48  1.53 to 6.97 0.35 to 5.25n  2.73 to 2.67

to to to to

11.37 1.79n  5.18n  2.89n

p o 0.05. p o0.001.

nn

3.3. The role of depressive symptom severity as a mediator The possible mediating role of depressive symptoms on QoL was examined through four bootstrapping mediational analyses (Table 2). In the first set of analyses, the independent variable was CGI-Severity, the mediating variable was depressive symptoms and the dependent variable was MOS-36 QoL domain (physical health, emotional health, social functioning, or general health). Bootstrapping confidence intervals revealed that depressive symptoms mediated the relationship between CGI-Severity and emotional health (  11.03; 95% CI 18.47 to  3.90) and general health (  5.94; 95% CI 11.20 to 2.04) QoL and partially mediated the effect between CGI-Severity and social functioning QoL ( 4.03; 95% CI 7.11 to 1.62). 3.4. The role of symptom interference or resistance against symptoms as mediators The possible mediating roles of interference of obsessivecompulsive symptoms and/or resistance against obsessivecompulsive symptoms on QoL were examined through two sets of four bootstrapping mediational analyses (Table 2). In the first set of analyses, the independent variable was CGI-Severity, the mediating variable was Y-BOCS interference of obsessivecompulsive symptoms and the dependent variable was MOS-36 QoL domain (emotional health, social functioning, or general health). Bootstrapping confidence intervals revealed that interference of obsessive-compulsive symptoms mediated the relationship between CGI-Severity and emotional health (11.79; 95% CI 21.24 to  1.79), social functioning ( 9.10; 95% CI  13.50 to  5.18) and

general health ( 9.04; 95% CI 14.99 to  2.89) QoL. In the second set of analyses, the mediating variable was the Y-BOCS resistance against obsessive-compulsive symptoms factor. Bootstrapping confidence intervals revealed that resistance against obsessivecompulsive symptoms partially mediated the relationship between obsessive-compulsive symptoms and social functioning QoL (2.16; 95% CI 0.35 to 5.25). Resistance against obsessive-compulsive symptoms did not mediate the relationship between CGI-Severity and emotional health (1.77; 95% CI 1.53 to 6.97) or general health QoL (0.12; 95% CI  2.73 to 2.67). The relationship between the three mediator variables and the QoL domains was further explored through a series of mediational analyses that utilized the CGISeverity rating as the new mediating variable and depressive symptom severity, interference of symptoms and resistance to symptoms as the independent variables. These analyses revealed that CGISeverity mediated the relationship between depressive symptom severity and social functioning QoL ( 0.18; 95% CI 0.44 to  0.04) as well as the relationship between resistance against symptoms and emotional health ( 1.96; 95% CI  4.57 to 0.52) and general health (1.11; 95% CI  2.56 to  0.24) QoL. Additionally, the CGI-Severity partially mediated the relationship between resistance against symptoms and social functioning QoL ( 1.62; 95% CI  2.92 to  0.71). Scores on the CGI-Severity did not mediate the relationship between interference of symptoms and any of the three QoL domains. 3.5. Multiple mediation model Due to the mediating roles of interference of obsessivecompulsive symptoms and the partially mediating role of resistance

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against obsessive-compulsive symptoms as well as depressive symptom severity on social functioning QoL, a third set of analyses was run to further investigate this outcome. In this analysis, interference of and resistance against symptoms as well as depressive symptom severity were entered at the same time as mediating variables, with CGI-Severity as the independent variable and social functioning QoL as the dependent variable. Interference of symptoms ( 11.00; 95% CI  15.72 to  7.02), resistance against symptoms (3.16; 95% CI 1.09 to 6.85), and depressive symptom severity ( 3.17; 95% CI 6.04 to  1.11) retained their significance. The effect was fully mediated by these three variables when entered together. Lastly, a mediational analysis was run to address the possible bidirectionality of the mediation pathway. As such, the three QoL domains of emotional health, social functioning, and general health were entered as the independent variables (three separate analyses), interference of and resistance against symptoms were entered as the mediators and CGI-Severity was entered as the dependent variable. The results of these mediational analyses were non-significant.

4. Discussion The current study reported on various factors associated with QoL in adults with OCD. A comparison of QoL across four psychiatric conditions including OCD, MDD, panic disorder and schizophrenia revealed several group differences. Interestingly, persons with OCD had significantly worse social functioning QoL than persons with any of the three other disorders explored. Social functioning may be deeply impacted by the time, interference and distress related to intrusive obsessions and reflexive compulsions (Lewin et al., 2011; Markarian et al., 2010). Additionally, symptoms may be time consuming and interfere with employment/academic success as well as time spent with family or friends, thereby limiting a person’s opportunities to experience functional and positive social interactions (Yaryura-Tobias et al., 2000). In addition to the lower social functioning QoL, those with OCD had significantly more diminished role emotional health and vitality/energy QoL as compared to those with panic disorder or schizophrenia and significantly worse mental health QoL relative to those with schizophrenia. It is possible that those with schizophrenia do not have as clear insight into their emotional health and mental health, which may be reflected in this finding (i.e., those with OCD recognize the extent of their illness and impairment in a different way from someone with schizophrenia). However, a person’s insight into their OCD, as well as symptom chronicity (Rasmussen and Eisen, 1994), may contribute to this detriment in emotional health and vitality/energy QoL. Additionally, those with OCD had significantly worse general health QoL than those with panic disorder, again highlighting the impact of obsessive-compulsive symptoms on daily functioning. Unfortunately, obsessive-compulsive symptoms may interfere with activities of daily living and may limit contact with friends and family members (Bobes et al., 2001). Functional and social impairment, in addition to the possibility of comorbid depression and other anxiety disorders may impact feelings of overall well-being, thereby diminishing general health QoL (Abramowitz et al., 2007; Huppert et al., 2009). Contrastingly, comparisons across disorders revealed that persons with OCD fared better in general health QoL than did those with MDD and had better physical health QoL than persons with MDD, panic disorder or schizophrenia. This finding is consistent with others that have shown that physical health QoL is not generally impacted by OCD (Goodman et al., 1989a; Rapaport et al., 2005). For all comparisons across psychiatric conditions, significant comorbidities in

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the OCD sample should be taken into account as potentially influential in QoL ratings. Consistent with previous research, obsessive-compulsive symptom severity was negatively correlated with emotional health, social functioning and general health QoL, but not physical health QoL (Masellis et al., 2003; Moritz et al., 2005; Eisen et al., 2006). These relations are likely a function of reduced role functionality in the person with OCD due to the interfering nature of symptoms, as well as other clinical features. On balance, these moderate relationships suggest that other factors (e.g., comorbidity) are relevant in QoL. Significant inverse correlations between age and both emotional health and social functioning QoL were found. The inverse relationship between age and social functioning QoL may be explained by increasing withdrawal from interpersonal relationships experienced by adults with OCD as they age in attempts to cope with their symptoms. The negative correlation between age and emotional health QoL may be explained by helplessness and hopelessness related to sustained illness. More specifically, older age may be associated with greater understanding of illness chronicity. After years of being ill, one might feel that they have exhausted all options for reducing symptoms and may feel that the disorder is interminable. Regarding gender, being female was negatively related to emotional health QoL, but not social functioning, general health or physical health QoL. It is possible that gender differences in depressive symptomology (e.g., self-worth, anhedonia) may contribute to the relationship between gender and emotional health QoL, as aversive feelings may be related to more negative emotionality (Huppert et al., 2009; Rapaport et al., 2005). Additionally, women may perceive significant role strain, which may increase negative feelings thereby decreasing emotional health QoL (Camporese et al., 1998). As depressive symptoms become a more prominent part of a person’s symptom profile, heightened withdrawal from routine activities may occur, thereby motivating declines in QoL across domains. Additionally, the combination of depressive and obsessive-compulsive symptoms may contribute to increased disease burden, thereby decreasing emotional health, social functioning, and general health QoL. Importantly, psychotherapeutic interventions must address both obsessive-compulsive symptoms and depressive symptoms to increase QoL (Storch et al., 2009). For some with comorbid OCD and depression, evidence-based treatment for OCD may be enough to reduce depressive symptoms. Others may require putative ingredients of depression treatment such as antidepressant medication, behavioral activation, cognitive restructuring, or attention to interpersonal relationships/functioning to improve QoL (Jakobsen et al., 2011; Thoma et al., 2011). Unique to this study was the exploration of the mediating role of interference of and resistance against obsessive-compulsive symptoms. Interference of obsessive-compulsive symptoms mediated the relationship between obsessive-compulsive severity and diminished emotional health, social functioning and general health QoL. The degree of symptom interference directly impacted the diminished QoL experienced by adults with OCD suggesting that interference of obsessive-compulsive symptoms is an underlying mechanism explaining the relationship between obsessive-compulsive severity and diminished emotional health, social functioning and general health QoL. Interference of symptoms may reduce engagement in routine (e.g., going to work) or pleasurable (e.g., seeing friends) activities. A higher degree of distress related to these symptoms may lead to role limitations and prevent time spent in more productive activities. The inability to participate in multiple aspects of daily functioning, including maintaining employment or academic success impedes on chronic illness coping and diminishes QoL across multiple domains.

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Resistance against obsessive-compulsive symptoms also partially mediated the relationship between obsessive-compulsive symptom severity and social functioning QoL. Contrarily to interference of symptoms, resistance against symptoms (i.e., effort to resist symptoms and perceived degree of control over symptoms) was related to increased social functioning QoL. Resistance against obsessive-compulsive symptoms may facilitate relatively healthier social functioning by virtue of the affected person ‘fighting’ to limit the impact of their symptoms on social functioning. Through such resistance, the person may experience increased instances in which their symptoms are less prominent and not associated with impairment. Importantly, these periods in which the person is not engaging in rituals may allow for adaptive experiences that compete with obsessive-compulsive symptoms. It is important to note that CGI-Severity ratings mediated the relationship between resistance against symptoms and emotional health, social functioning (partial mediation) and general health QoL suggesting that less resistance against symptoms predicted more severe OCD yielding more impairment across QoL domains. This study has several limitations worth noting. First, the demographic homogeneity of the sample limits its generalizability. Second, several demographic and clinical variables (e.g., SES, time since onset) were not available. Third, different methodologies were utilized for each of the historical samples with differing psychopathologies used to compare QoL across conditions. In the future, it would be ideal to recruit prospectively and to utilize historical samples with highly similar methodologies. Fourth, statistical power was not adequate to examine moderating variables such as gender or depressive symptoms despite their theoretical relevance. Last, these results do not imply causality and should not be interpreted as such. Future research may attempt to investigate quality of life longitudinally in order to properly display the causative effects of OCD symptoms and severity on QoL. In lieu of these limitations, this study sheds light onto the contributing factors associated with diminished QoL in adults with OCD and has important clinical and scientific implications. It is essential to consider the role of QoL when working clinically with persons with OCD. In order to gain clinical remission, not only do obsessive-compulsive symptoms need to be eradicated, but QoL needs to be targeted for improvement. Psychopharmacological therapy with SRIs and psychotherapeutic treatments utilizing CBT are widely used for the treatment of OCD (Goodman et al., 1989b; Storch et al., 2004). Attenuation of obsessivecompulsive symptoms with these treatments is often directly related to improvements in varying domains of QoL (Diefenbach et al., 2007; Frost et al., 2011; Goodman et al., 1989a; Koran et al., 2010). However, despite the efficacy of both CBT and psychopharmacology, these treatments may not target QoL directly and implicitly assume that QoL will improve once symptoms are reduced. Treatments specifically aimed at improving daily functioning for the long-term must be incorporated into psychotherapy with the goal of significantly enhancing QoL (Bystritsky et al., 2001). A two-tiered approach, outlined by Bystritsky et al. (2001) suggests that initial treatments for those with significantly impacted QoL must aim to reduce obsessive-compulsive symptoms as they impede QoL and hinder the person’s ability to excel in psychosocial functioning. Subsequently, this treatment must be followed by psychosocial rehabilitation which strives to increase QoL by improving social functioning, enhancing coping techniques and aiding with practical goals such as finding appropriate employment. The mediating role of interference of symptoms, resistance against symptoms and depressive symptom severity helps better our understanding of what exactly impacts QoL in persons with

OCD. In addition to including psychosocial rehabilitation, CBT for OCD must directly target the reduction of interference and increase efforts to resist symptoms. Knowing that resistance against symptoms is associated with social functioning QoL is important to clinical practice; treatment can be tailored to improve social functioning QoL by incorporating homework involving increased social interactions such as volunteering in the community or setting aside time to spend with family and/or friends. Motivational interviewing may be useful in enhancing exposure and response prevention techniques by encouraging resistance against symptoms during anxiety-provoking situations thereby decreasing responses to obsessive-compulsive triggers (Storch et al., 2009; Whisman et al., 2000). Ultimately, treatment for OCD should focus on symptom reduction, including both obsessive-compulsive symptoms as well as comorbid depressive symptoms, and on the improvement of QoL and daily functioning through psychosocial rehabilitation and the maintenance of symptom attenuation or eradication.

Acknowledgments The contributions of Joseph Vandello, Ph.D., Kevin Thompson, Ph.D. and Marni Jacob are greatly appreciated.

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