Predictors of functional impairment in pediatric obsessive-compulsive disorder

Journal of Anxiety Disorders 24 (2010) 275–283

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Journal of Anxiety Disorders

Predictors of functional impairment in pediatric obsessive-compulsive disorder Eric A. Storch a,b,c,*, Michael J. Larson d, Jordana Muroff e, Nicole Caporino c, Daniel Geller f, Jeannette M. Reid a, Jessica Morgan a, Patrice Jordan a, Tanya K. Murphy a,b a

Department of Pediatrics, University of South Florida, United States Department of Psychiatry, University of South Florida, United States c Department of Psychology, University of South Florida, United States d Department of Psychology, Brigham Young University, United States e School of Social Work, Boston University, United States f Department of Pediatric Psychopharmacology, Massachusetts General Hospital, United States b

A R T I C L E I N F O

A B S T R A C T

Article history: Received 10 September 2009 Received in revised form 10 December 2009 Accepted 10 December 2009

The current study examined factors associated with obsessive-compulsive disorder (OCD) related functional impairment among 99 youth with OCD. A trained evaluator administered the Children’s YaleBrown Obsessive-Compulsive Scale, items assessing family accommodation, and a version of the Brown Assessment of Beliefs Scale that was modified for children. Youth completed the Child ObsessiveCompulsive Impact Scale-Child Version, Obsessive-Compulsive Inventory-Child Version, Multidimensional Anxiety Scale for Children, and Children’s Depression Inventory-Short Form. The child’s parent completed the Child Obsessive-Compulsive Impact Scale-Parent Version. Results indicated that OCD symptom severity, depressive symptoms, and family accommodation were directly related to impairment, while insight was inversely related to functional impairment. Insight, family accommodation, and depressive symptoms predicted parent- and/or child-rated functional impairment above and beyond OCD symptom severity. Among symptom dimensions, contamination/cleaning and aggressive/ checking symptoms were the only dimensions significantly associated with impairment. Assessment and treatment implications are discussed; specifically, we highlight how the variables of interest may impact clinical presentation and treatment course. ß 2009 Elsevier Ltd. All rights reserved.

Keywords: Obsessive-compulsive disorder Children Impairment Disability Treatment Anxiety

Obsessive-compulsive disorder (OCD) is an anxiety disorder that is characterized by presence of obsessions and/or compulsions that are distressing and potentially disabling to the affected individual (American Psychiatric Association [APA], 2000). Although a considerable body of research exists on the nature of obsessive-compulsive symptoms and the overall phenomenology of OCD, only recently has attention been given to functional impairment and quality of life among those with OCD. Most of these studies have examined functional impairment in adult samples, with findings extrapolated to inform upon pediatric OCD patients. However, children differ from adults in a number of important ways, including position within a family system; domains of impairment (e.g., school versus work); and clinical characteristics (e.g., presence of insight is not necessary among youth with OCD, but comprises a diagnostic criterion for adults;

* Corresponding author at: Department of Pediatrics, University of South Florida, 800 6th Street South 4th Floor, St. Petersburg, FL 33701, United States. Tel.: +1 727 767 8230; fax: +1 727 767 7786. E-mail address: [email protected] (E.A. Storch). 0887-6185/$ – see front matter ß 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.janxdis.2009.12.004

Freeman et al., 2003). Accordingly, we sought to directly examine variables theoretically associated with OCD-related functional impairment among affected youth. As noted, the majority of research examining functional impairment in OCD has utilized adult participants. Not surprisingly, adults with OCD exhibit greater levels of functional impairment relative to the general United States population. Those with OCD report significantly more work-related impairments (e.g., higher unemployment rate, lower socio-economic status; Huppert, Simpson, Nissenson, Liebowitz, & Foa, 2009; Karno, Golding, Sorenson, & Burnam, 1988); disruption of social and marital relationships (Huppert et al., 2009; Karno et al., 1988; Koran, Thienemann, & Davenport, 1996); and physical health concerns (as evidenced by greater frequency/extent of medical utilization and hospitalization; Barlow, 2002). Further, adults with OCD report quality of life levels comparable to those found in association with schizophrenia (Stengler-Wenzke et al., 2006) and depression (Bobes et al., 2001), and significantly lower than reported by healthy controls (Bobes et al., 2001; RodriguezSalgado et al., 2006; Stengler-Wenzke et al., 2006). In adults with OCD, quality of life is strongly related to degree of functional

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impairment (Huppert et al., 2009), as is OCD symptom severity (Eisen et al., 2006; Lochner et al., 2003; Masellis, Rector, & Richter, 2003; Rapaport, Clary, Fayyad, & Endicott, 2005; RodriguezSalgado et al., 2006; Sorensen, Kirkeby, & Thomsen, 2004). In a recent study involving 87 adults with OCD, severity of OCD symptoms; depressive and anxious symptoms; and the tendency to misinterpret the significance of intrusive thoughts were all related to functional impairment (Storch, Abramowitz, & Keeley, 2009). Depressive symptoms and the degree to which a patient both attempted to resist and was able to control OCD symptoms uniquely predicted functional impairment. These two variables fully mediated the relationship between OCD-related distress and functional impairment (Storch et al., 2009). Among children, significant functional impairment has been endorsed by up to 90% of youth with OCD and has been related to symptom severity (Lack et al., 2009; Piacentini, Bergman, Keller, & McCracken, 2003; Valderhaug & Ivarsson, 2005). Although such findings are important, the role of other clinical factors in explaining impairment remains unclear. Conceptually, we were interested in how several variables that have shown great import in the clinical presentation of pediatric OCD – patient’s level of insight, family accommodation, and associated depressive and anxiety symptoms – may clarify the relationship between OCD symptom severity and functional impairment. These variables were chosen given their role in clinical presentation; treatment course; and treatment outcome (e.g., Keeley, Storch, Merlo, & Geffken, 2008). There are several conceptual ways that each of these variables may relate to functional impairment. First, poor insight (i.e., low recognition of the senselessness of one’s obsessions and compulsions; e.g., Kozak & Foa, 1994) may contribute to functional impairment by virtue of its association with poor treatment response (Storch, Milsom, et al., 2008). Those with poorer insight may be less willing to participate in treatment, and less likely to resist symptom engagement – thus increasing the changes of prolonged functional impairment. Second, family accommodation defined as actions taken by family members to facilitate rituals (e.g., provide required objects or answer repeated questions), acquiesce the child (e.g., alter routines to minimize anxiety), or decrease responsibility (e.g., minimize disciplinary actions or provide extra homework/chore assistance) may paradoxically contribute to functional impairment (Peris et al., 2008; Steketee & Van Noppen, 2003; Storch, Geffken, Merlo, Jacob, et al., 2007) by reinforcing a child’s rituals and/or avoidance behaviors. Third, adults with comorbid depression evidence greater functional impairment than do those with OCD alone (Abramowitz et al., 2007; Tu¨kel et al., 2002, 2006), suggesting that depressive symptoms may relate meaningfully to functional impairment in youth with OCD as well. Fourth, non-OCD anxiety symptoms may moderate the association between OCD symptom severity and functional impairment. Research on Swiss adults with OCD suggested greater impairment among those with (versus without) a comorbid anxiety disorder (Angst et al., 2005). There are important clinical implications for elucidating predictors of functional impairment among pediatric OCD patients. Knowledge of functional impairment predictors in youth would allow for more tailored interventions geared toward minimizing long-term debilitation. For instance, pharmacotherapy (concurrent with cognitive-behavioral therapy (CBT)) may be indicated in cases where poor insight would otherwise preclude successful implementation of exposure exercises. As well, family accommodation and/or comorbid depression/non-OCD anxiety symptoms may require initial treatment attention, otherwise impeding OCD treatment. This study empirically examined possible predictors of functional impairment over and above symptom severity. On the basis of empirical findings in both adults and children, as well as our clinical experiences, we derived the following questions and

hypotheses. First, what are the relations among parent- and childrated functional impairment and OCD symptom severity; patient insight; family accommodation; depressive symptoms; and nonOCD anxiety symptoms? We expected that both parent- and childrated functional impairment would be significantly and positively related with OCD symptom severity, as well as with degree of family accommodation; depressive symptoms; and non-OCD anxiety symptoms. We expected that both parent- and childrated functional impairment would be negatively related to patient insight. Second, would the clinical variables of insight; family accommodation; depressive symptoms; and non-OCD anxiety symptoms predict parent- and child-rated impairment over and above OCD symptom severity? We hypothesized that the variables listed above would predict parent- and child-rated functional impairment after accounting for OCD symptom severity. Finally, we explored whether certain symptom dimensions (i.e., symmetry/ordering, contamination/cleaning, sexual/religious obsessions, aggressive/checking, and hoarding) were differentially related to functional impairment. 1. Method 1.1. Participants Participants included 99 children and adolescents (37 female) and their parent(s) who presented at one of two university-based clinics specializing in the treatment of pediatric OCD. The youth ranged in age from 6 to 17 years (M = 12.84  2.81 years). The vast majority of participants was Caucasian (90%; n = 89) with the remaining youth self-identifying as Hispanic (n = 3), African-American (n = 2), or other (n = 2). Three participants did not report information regarding race. Parents who participated in the study were generally well educated; over 80% of both the mothers and fathers graduated from high school and over 50% of both the mothers and fathers had a college degree. Approximately 12% of families had an income less than $50,000, 38% of families had an income between $50,000 and $100,000, and 50% of families had an income above $100,000. The majority of youth were on a psychotropic medication (67%). Participants were formally diagnosed with OCD according to the criteria outlined in the DSM-IV-TR (APA, 2000). Diagnoses were determined through a 90-min semi-structured clinical interview with the participant and his/her caregiver(s) conducted with a psychiatrist or psychologist with considerable experience in pediatric OCD. After the interview, additional clinical information (i.e., responses to measures) was reviewed as appropriate to assist with diagnostic decisions. If necessary, the primary clinician discussed his/her clinical impressions and measurement data with a second clinician to determine consensus diagnoses. There were no instances of disagreement for the primary diagnosis of OCD. In the rare instance that there was a disagreement about a comorbid diagnosis, the disagreement was resolved via discussion. Potential participants were excluded if they met any of the following criteria: (a) history of and/or current psychosis, autism-spectrum disorders (including Pervasive Developmental Disorder, not otherwise specified), bipolar disorder, or current suicidality; (b) principal diagnosis other than OCD; (c) a positive diagnosis in the caregiver of mental retardation, psychosis, or other psychiatric disorders or conditions (i.e., dementia) that would limit their ability to provide consent. 1.2. Measures 1.2.1. Child Obsessive-Compulsive Impact Scale-Child and Parent Versions (COIS-C/P) The COIS-C/P (Piacentini & Jaffer, 1999) are 58-item, self-report or parent-report measures, which assess the extent to which

E.A. Storch et al. / Journal of Anxiety Disorders 24 (2010) 275–283

pediatric OCD causes impairment in specific areas of child psychosocial functioning. The COIS-C/P assess difficulties in school activities (16 items), home/family activities (17 items), and social activities (19 items). Respondents rate the extent to which OCD interferes with the child’s functioning in each area using a 4-point scale ranging from ‘‘not at all’’ to ‘‘very much.’’ The COIS-C/P have demonstrated good internal consistency, construct validity, and convergent validity (Piacentini et al., 2003). The internal consistency of the COIS-C/P in the current sample was a = .96 and .97, respectively. 1.2.2. Children’s Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) The CY-BOCS (Scahill et al., 1997) is a clinician-rated, semistructured inventory of OCD symptoms and severity. The CY-BOCS consists of two subscales: Obsessions Severity (5 items) and Compulsions Severity (5 items), which are combined to create a Total Score. Items are rated on a 5-point Likert scale assessing the severity of symptoms (i.e., distress, frequency, interference, and resistance) and the child’s control over his/her symptoms. Since many youth underestimate their symptoms, the CY-BOCS was administered to both the child and parent(s) jointly. The CY-BOCS is considered the ‘‘gold standard’’ measure of pediatric OCD, based on its reliability, validity (Scahill et al., 1997; Storch et al., 2004), and treatment sensitivity (e.g., POTS, 2004). Cronbach’s a for the CY-BOCS Total Score in the current sample was a = .86. The CY-BOCS Symptom Checklist can be subdivided into specific symptom dimensions. A review study examining the different possible factor-analytic separations of OCD symptom dimensions (Mataix-Cols, Rosario-Campos, & Leckman, 2005) supported the validity of a five factor model containing the dimensions of symmetry/ordering, contamination/cleaning, sexual/religious obsessions, aggressive/checking, and hoarding. Consistent with previous studies (Mataix-Cols, Marks, Greist, Kobak, & Baer, 2002; Rufer, Fricke, Moritz, Kloss, & Hand, 2006; Storch, Merlo, et al., 2008), presence of a primary symptom on the CYBOCS Symptom Checklist was coded as 1; its absence was coded as 0. Scores on the five factor-analytically derived symptom dimensions (symmetry/ordering, contamination/cleaning, sexual/religious obsessions, aggressive/checking, and hoarding) were derived by summing the scores of the symptom categories for each dimension. 1.2.3. Obsessive-compulsive Inventory-Child Version (OCI-CV) The OCI-CV (Foa et al., in press) is a 21-item self-report measure of OCD symptoms. Symptoms are rated on a 3-point Likert scale that yields symptom severity scores across six domains (e.g., washing, hoarding, ordering, etc.). The OCI-CV is internally consistent (a > .81) and shows strong test-retest reliability (Foa et al., in press). The internal consistency of the OCI-CV total score in this study was adequate (a = .82). 1.2.4. Children’s Depression Inventory-Short Form (CDI-S) Based on the full-length CDI, the CDI-S (Kovacs, 1992) is an abbreviated 10-item child-report measure of depressive symptoms experienced over the past two weeks. Items are rated on a 0– 2 scale with higher scores corresponding to more severe symptoms. The CDI-S has generally strong psychometric properties (Kovacs, 1992), with good internal consistency in the current sample (a = .85).

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stability, and excellent construct validity (March et al., 1997, 1999). The MASC total score exhibited excellent internal consistency in this sample (a = .90). 1.2.6. Family accommodation (FA) Family accommodation was assessed using the 13 items generated by Calvocoressi et al. (1995) that assess the degree to which family members have accommodated the child’s OCD symptoms during the previous month (9 items) and the level of distress/impairment that the family members and patient experience as a result of the family accommodating or not accommodating the child (4 items). These items have demonstrated good psychometric properties including good internal consistency (a = .76–.80; Calvocoressi et al., 1995; Geffken et al., 2006) and correlations with OCD symptom severity and impairment (Storch, Geffken, Merlo, Jacob, et al., 2007; Storch, Geffken, Merlo, Mann, et al., 2007). In the current sample, the internal consistency of the sum of these family accommodation items is a = .91. 1.2.7. Brown Assessment of Beliefs Scale-Modified for Children (BABS-C) Children’s insight into their obsessive-compulsive symptoms was assessed through a modified version of the Brown Assessment of Beliefs Scale (BABS; Eisen, Phillips, Beer, Atala, & Rasmussen, 1998), a widely used and psychometrically sound clinician-rated measure of adult patient insight. Revisions primarily included making the wording appropriate for children to understand and removing the item that pertains to explaining differing views as our piloting of the measure suggested that some children struggled to understand this. Like the BABS, items are scored on a 0 (normal) to 4 (pathological) scale and summed to produce a total score (range = 0–20). Strong psychometric properties have been reported for the BABS in adults with OCD (e.g., Eisen et al., 1998, 2001) and schizophrenia (e.g., Kaplan et al., 2006). The internal consistency for the BABS-C was acceptable, with a Cronbach’s a of .82. 1.3. Procedures The institutional review boards at both universities granted permission to conduct this study. At their initial treatment evaluation across sites, families were invited to participate. After written consent and assent was obtained, a trained clinician administered the CY-BOCS to parents and children jointly, the FA items to parents alone; and the insight items to children and parents separately. Together with clinician judgment, parent and child responses were used to determine CY-BOCS severity ratings. On the insight items, the clinician made an overall judgment about patient insight that was based on parent and child ratings and his/ her clinical judgment. Rater training consisted of the following: an instructional meeting about the nature of OCD, commonly comorbid diagnoses, training on how to administer the CY-BOCS, FA items, and BABS-C, observation of at least five administrations by a trained clinician, and administration of five or more batteries under direct observation. Weekly rater meetings were held at each site to discuss participant ratings and promote quality assurance. After the CY-BOCS, FA items, and BABS-C items were administered, parents completed relevant study measures. No compensation was given for participation. 1.4. Data analysis

1.2.5. Multidimensional Anxiety Scale for Children (MASC) The MASC (March, Parker, Sullivan, Stallings, & Conners, 1997) is a 39-item, self-report measure of anxiety symptoms in children. Items are rated on a 4-point scale and summed to derive a total score. The MASC has demonstrated strong psychometric properties, such as excellent internal consistency; adequate test-retest

We first generated descriptive statistics for all measures. Zeroorder correlations assessed the univariate relationships between each psychometric measure. Hierarchical regression analyses were then used to determine the independent predictors of functional impairment. All hierarchical regression models included measures

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278 Table 1 Zero-order correlations among study variables.

CY-BOCS Total Score CY-BOCS Resistance OCI-CV Total Score CDI-S Total Score MASC Total Score FA Total Score BABS-C Total Score COIS-P Total Score COIS-P School COIS-P Home COIS-P Social COIS-C Total Score COIS-C School COIS-C Home COIS-C Social

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

1.00 .81** .30** .27** .09 .48** .03 .41** .37** .41** .32** .41** .27** .35** .40**

1.00 .20* .20* .08 .35** .21* .21* .20* .24** .19* .27** .15 .21* .31**

1.00 .35** .45** .27** .05 .29** .22* .31** .14 .36** .34** .35** .25*

1.00 .42** .20* .16 .27** .22* .26* .26* .38** .35** .27** .34**

1.00 .07 .21* .08 .04 .07 .03 .20 .23* .12 .16

1.00 .13 .54** .47** .60** .45** .44** .40** .38** .36**

1.00 .23* .18 .23* .27** .18 .06 .22* .17

1.00 .92** .81** .77** .62** .56** .62** .48**

1.00 .69** .63** .60** .59** .57** .48**

1.00 .65** .57** .44** .61** .47**

1.00 .48** .27** .46** .50**

1.00 .87** .92** .90**

1.00 .78** .63**

1.00 .74**

1.00

Note: CY-BOCS – Children’s Yale-Brown Obsessive-Compulsive Scale; OCI-CV – Obsessive-compulsive Inventory-Children’s Version; CDI-S – Children’s Depression InventoryShort Form; MASC – Multidimensional Anxiety Scale for Children; FA – Family Accommodation total score; BABS-C – Brown Assessment of Beliefs Scale-Modified for Children; COIS-P – Child Obsessive-Compulsive Impact Scale-Parent Rating; COIS-C – Child Obsessive-Compulsive Impact Scale-Child Rating. * p < .05. ** p < .01.

of OCD symptom severity (CY-BOCS total and OCI-CV total) in the first block, measures of emotional functioning (CDI and MASC scores) in the second block, and measures of family accommodation and insight (FA and BABS-C scores) in the third block. Symptom resistance was not included in the models due to its high correlation with the CY-BOCS total score (i.e., due to multicollinearity between the variables). Dependent variables included the parent and child ratings of functional impairment as measured by the COIS total score. Separate subsequent analyses utilized the same order of entry for the independent variables, with each of the COIS subscales (School, Home, and Social) as dependent variables. We reported the variance inflation factor (VIF) for all regression models to ensure the independent variables were not multicollinear (Kleinbaum, Kupper, Muller, & Nizam, 2007). Given that this is the first study to examine the predictors of OCD-related functional impairment in children, we used an alpha level of .05 for interpretation of all results. 2. Results Zero-order univariate correlations between measures of functional impairment, OCD symptom severity, family accommodation, insight, and emotional functioning are presented in Table 1. Parent- and child-rated impairment was moderately related to OCD symptom severity on the CY-BOCS and OCI-CV and depressive symptoms, but only weakly related to OCD symptom resistance. Parent- and child-rated impairment was moderately-to-strongly related to family accommodation, and weakly related to anxiety symptoms. Insight was inversely related to functional impairment with correlations of weak-to-moderate strength. 2.1. Regression analysis for overall parent-rated functional impairment There does not appear to be excessive collinearity among the independent variables used for the regression analyses as the strongest univariate correlation between two independent variables was for FA Total Score and the parent rating of the COIS Home subscale at r = .60, p < .01, and the VIFs for the multiple regression models were relatively low (see Tables 2–5; Kleinbaum et al., 2007). Findings of the hierarchical regression model with parentrated functional impairment (i.e., COIS-P Total) as the dependent variable are summarized in Table 2. Measures of symptom severity were significant predictors of parent-rated functional impairment,

explaining 20% of the variance (p < .001). Addition of measures of depressive and anxiety symptoms did not significantly add to the model, explaining only an additional 2% of the variance (p = .29). Addition of measures of insight and family accommodation significantly improved the model (p < .001) and accounted for an additional 17% of the variance in parent-rated functional impairment. Results of the overall model suggest that emotional functioning does not explain additional variance in functional impairment beyond OCD severity, but that both family accommodation and symptom insight are predictive of functional impairment beyond OCD symptom severity and emotional functioning. In addition, family accommodation is slightly more predictive of functional impairment than insight to symptoms. 2.2. Regression analysis for overall child-rated functional impairment The hierarchical regression model for child-rated functional impairment (i.e., COIS-C Total as the dependent variable) is presented in Table 2. Consistent with the findings from the model of parent-rated functional impairment above, measures of symptom severity significantly predicted functional impairment (p < .001) and accounted for 23% of the variance. Measures of emotional functioning (i.e., depressive and anxiety symptoms) added to the model at a trend level of significance (p = .06), but only accounted for an additional 5% of the variance. Addition of family accommodation and insight significantly improved the model, explaining an additional 9% of the variance in child-rated functional impairment. In the final model, both family accommodation and insight predicted functional impairment; symptoms of depression were an additional significant predictor in the model. Thus, while the pattern of results is generally similar to that of the parent ratings, the contribution of depression symptoms to functional impairment was more apparent in the child ratings. 2.3. Regression analyses of specific areas of impairment We next examined predictors of specific aspects of functional impairment, including functioning in the school, home, and social environments by conducting three additional separate hierarchical regression models with COIS-rated impairment specific to these environments as the dependent variables (see Tables 3 and 4). For all three situation-specific parent ratings, symptoms of OCD severity were significant predictors of functional impairment (ps < .005) accounting for 15%, 21%, and 11% of the variance in

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279

Table 2 Hierarchical regression model for overall parent-rated (first regression) and child-rated (second regression) functional impairment. Variables COIS-Parent Total 1st Block CY-BOCS Total OCI-CV Total

R2

R2 change

R2 change, p value

20

.20

<.001

2nd Block CDI-S Total MASC Total

.22

3rd Block FA Total BABS-C Total

.39

COIS-Child Total 1st Block CY-BOCS Total OCI-CV Total

.23

2nd Block CDI-S Total MASC Total

.28

3rd Block FA Total BABS-C Total

.37

.02

.17

.23

.05

.09

B (std. error)a

Betaa

p valuea

VIF

.92 (.55) .54 (.46)

.16 .12

.10 .24

1.4 1.4

1.20 (.73) .06 (.20)

.16 .03

.10 .76

1.3 1.5

1.04 (.27) 1.64 (.67)

.37 .21

.001 .02

1.4 1.1

1.01 (.52) .67 (.43)

.19 .15

.06 .13

1.4 1.4

1.77 (.69) .06 (.19)

.25 .03

.01 .73

1.3 1.5

.59 (.25) 1.50 (.64)

.23 .21

.02 .02

1.4 1.1

.29

<.001

<.001

.06

.002

Note: COIS – Child Obsessive-Compulsive Impact Scale; CY-BOCS – Children’s Yale-Brown Obsessive-Compulsive Scale; OCI-CV – Obsessive-compulsive Inventory-Children’s Version; CDI-S – Children’s Depression Inventory-Short Form; MASC – Multidimensional Anxiety Scale for Children; FA – Family Accommodation total score; BABS-C – Brown Assessment of Beliefs Scale-Modified for Children. a Coefficients reported are for the final model.

Table 3 Hierarchical regression model for situational parent-rated functional impairment. Variables COIS-P-School 1st Block CY-BOCS Total OCI-CV Total

R2

R2 change

R2 change, p value

.15

.15

<.001

2nd Block CDI-S Total MASC Total

.16

3rd Block FA Total BABS-C Total

.28

COIS-P-Home 1st Block CY-BOCS Total OCI-CV Total

.21

2nd Block CDI-S Total MASC Total

.23

3rd Block FA Total BABS-C Total

.44

COIS-P-Social 1st Block CY-BOCS Total OCI-CV Total

.11

2nd Block CDI-S Total MASC Total

.16

3rd Block FA Total BABS-C Total

.31

.01

.12

.21

.02

.21

.11

.05

.15

B (std. error)a

Betaa

p valuea

VIF

.32 (.21) .10 (.17)

.16 .06

.12 .57

1.4 1.4

.37 (.27) .03 (.07)

.14 .05

.18 .66

1.3 1.5

.31 (.10) .42 (.25)

.33 .15

.002 .10

1.4 1.1

.25 (.18) .21 (.15)

.13 .13

.16 .16

1.4 1.4

.34 (.23) .03 (.06)

.13 .05

.15 .60

1.3 1.5

.42 (.09) .50 (.22)

.45 .19

.001 .02

1.4 1.1

.29 (.25) .01 (.20)

.12 .01

.24 .95

1.4 1.4

.79 (.32) .09 (.09)

.24 .11

.02 .32

1.3 1.5

.37 (.12) .80 (.30)

.31 .24

.003 .008

1.4 1.1

.37

.001

<.001

.31

<.001

.005

.06

<.001

Note: COIS-P – Child Obsessive-compulsive Impact Scale—Parent Report; CY-BOCS – Children’s Yale-Brown Obsessive-Compulsive Scale; OCI-CV – Obsessive-compulsive Inventory-Children’s Version; CDI-S – Children’s Depression Inventory-Short Form; MASC – Multidimensional Anxiety Scale for Children; FA – Family Accommodation total score; BABS-C – Brown Assessment of Beliefs Scale-Modified for Children a Coefficients reported are for the final model.

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280

Table 4 Hierarchical regression model for situational child-rated functional impairment. Variables COIS-P-School 1st Block CY-BOCS Total OCI-CV Total

R2

R2 change

R2 change, p value

.15

.15

<.001

2nd Block CDI-S Total MASC Total

.19

3rd Block FA Total BABS-C Total

.27

COIS-P-Home 1st Block CY-BOCS Total OCI-CV Total

.19

2nd Block CDI-S Total MASC Total

.21

3rd Block FA Total BABS-C Total

.30

COIS-P-Social 1st Block CY-BOCS Total OCI-CV Total

.18

2nd Block CDI-S Total MASC Total

.23

3rd Block FA Total BABS-C Total

.30

.04

.08

.19

.02

.09

.18

.05

.07

B (std. error)a

Betaa

p valuea

VIF

.04 (.18) .22 (.15)

.03 .16

.80 .14

1.4 1.4

.47 (.23) .04 (.06)

.21 .06

.05 .57

1.3 1.5

.24 (.09) .17 (.22)

.29 .07

.006 .44

1.4 1.1

.28 (.18) .32 (.15)

.16 .22

.12 .04

1.4 1.4

.37 (.24) .02 (.06)

.16 .03

.12 .76

1.3 1.5

.16 (.09) .54 (.22)

.19 .23

.07 .02

1.4 1.1

.54 (.22) .05 (.18)

.26 .03

.01 .77

1.4 1.4

.69 (.29) .04 (.08)

.24 .06

.02 .57

1.3 1.5

.15 (.11) .62 (.26)

.15 .21

.16 .02

1.4 1.1

.08

.01

<.001

.34

.005

<.001

.07

.01

Note: COIS-P – Child Obsessive-compulsive Impact Scale-Parent Report; CY-BOCS – Children’s Yale-Brown Obsessive-Compulsive Scale; OCI-CV – Obsessive-compulsive Inventory-Children’s Version; CDI-S – Children’s Depression Inventory-Short Form; MASC – Multidimensional Anxiety Scale for Children; FA – Family Accommodation total score; BABS-C – Brown Assessment of Beliefs Scale-Modified for Children a Coefficents reported are for the final model.

school-, home-, and social-related functional impairment, respectively. Emotional functioning did not significantly improve upon any of the models (ps > .06), but family accommodation and insight improved the prediction of functional impairment in each specific context, accounting for an additional 12% of the variance in the school environment, 21% of the variance in the home environment, and 15% in the social environment. Examination of the final models indicates family accommodation was the only significant predictor of functioning in the school environment, family accommodation and insight were significant predictors of functioning in the home environment, and family accommodation, insight, and symptoms of depression were significant predictors of functioning in the social setting (see Table 3). Results for child ratings of functioning in the school, home, and social environments were similar to the parent ratings (see Table 4). Specifically, symptoms of OCD severity were significant predictors of functional impairment in all three settings (ps < .001) accounting for 15%, 19%, and 18% of the variance in functioning in the school-, home-, and social-settings, respectively. Once again, emotional functioning did not significantly improve upon the variance accounted for by OCD severity (ps > .07), while family accommodation and insight accounted for significantly more variance in functional impairment in each of the school- (8% increase), home- (9% increase), and social environments (7% increase). Examination of the pattern of individual variable contributions in the final models, however, yielded an interesting pattern of differences from the models of parent-rated functional impairment. Family accommodation and depressive symptoms significantly predicted child-rated functional impairment at

school. In the home environment, OCD symptom severity, as measured by the OCI-CV, and level of insight were significant predictors, while level of insight, depression symptoms, and OCD symptom severity as measured by the CY-BOCS predicted functional impairment in the social setting (see Table 4). The pattern of results for child-rated functional impairment is much more variable than those for the parent ratings and includes depression levels and OCD symptom severity to a greater degree than seen with the parent ratings of functioning. 2.4. Symptom dimensions Zero-order correlations between measures of OCD symptom dimensions from the CY-BOCS Symptom Checklist and measures of functional impairment indicated parent ratings of functional impairment were weakly-to-moderately related to the contamination dimension across the school, r = .21, p < .05, home, r = .33, p < .01, and social environments, r = .22, p < .05, and weakly related to the aggression/checking dimension, primarily in the school environment, r = .24, p < .05. Child ratings of impairment were weakly-to-moderately associated with the aggression/ checking dimension in each of the school, r = .30, p < .01, home, r = .24, p < .05, and social environments, r = .21, p < .05. 3. Discussion The purpose of this study was to clarify the nature of functional impairment among youth with OCD by examining the differential contributions of OCD symptom severity; insight; family accom-

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modation; and both depressive and anxiety symptoms. We also sought to assess whether certain OCD symptom dimensions are differentially related to functional impairment. As expected, based on previous findings (Piacentini et al., 2003; Piacentini, Peris, Bergman, Chang, & Jaffer, 2007; Valderhaug & Ivarsson, 2005), OCD symptom severity predicted overall and context-specific impairment as rated by parents and children. After accounting for OCD symptom severity, poorer insight predicted impairment in two of three domains examined: home and social realms (but not school). This is consistent with others (Storch, Merlo, et al., 2008; Storch, Milsom, et al., 2008) and current thinking that motivation to resist/challenge one’s symptoms necessitates insight into their insensible nature. An alternative explanation is that these children are more motivated than children who lack insight to conceal their rituals when interacting with peers and relatives, thereby reducing the extent to which their OCD symptoms interfere with interpersonal relationships. The latter possibility could account for the finding that insight did not predict school-related impairment, as many school activities (e.g., completing homework) are solitary and compulsions that are likely to have a direct effect school functioning (e.g., rereading) could more easily be carried out without drawing attention to oneself. As well, and consistent with prior findings (e.g., Merlo et al., 2009; Storch, Geffken, Merlo, Jacob, et al., 2007), family accommodation predicted parent-rated impairment in all three domains of functioning examined (school, home, social) after accounting for OCD symptom severity. These findings, taken together with previous research indicating that decreases in family accommodation predict treatment outcome (Merlo et al., 2009), support the hypothesis that accommodating obsessive-compulsive symptoms serves to increase associated impairment even though clinical observations suggest that parents are often motivated by the expectations of the opposite effect (Storch, Geffken, Merlo, Jacob, et al., 2007; Storch, Geffken, Merlo, Mann, et al., 2007). Beyond increasing symptom severity by reinforcing ritual engagement, family accommodation might contribute to functional impairment by limiting children’s opportunities to develop problem solving skills related to coping with anxiety-provoking stimuli in addition to putting a strain on relationships with family members (e.g., Steketee & Van Noppen, 2003). Interestingly, family accommodation predicted child-rated impairment in school functioning only. It has been suggested that children are less likely than parents to view symptoms as impairing because they have fewer opportunities to observe decreases in functioning to the extent that their families are engaging in accommodation (Storch, Geffken, Merlo, Jacob, et al., 2007; Storch, Geffken, Merlo, Mann, et al., 2007). However, impairment might be more salient to children when they are at school because activities are mandatory and their families are not present to facilitate rituals; thus, symptoms are experienced as burdensome. The possibility that friends accommodate symptoms outside of the classroom setting, where there are fewer expectations for their own behavior, could explain why children with OCD do not perceive substantial impairment in social situations. Depressive symptoms also predicted functional impairment after accounting for OCD symptom severity, but only child-rated (i.e., not parent-rated) impairment. It may be that depressionrelated information processing biases or negative cognitive styles (Tibremont & Braet, 2004; Timbremont, Braet, Bosmans, & Van Vlierberghe, 2008) affected children’s perceptions of their OCDrelated impairment. Or, children with comorbid depressive symptoms may have difficulty delineating the cause of impairment, resulting in inflated OCD ratings. Alternatively, parents may not be as cognizant of the degree to which depressive symptoms (i.e., internalizing symptoms) play a role in their children’s impairment (Mancebo et al., 2006).

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Somewhat surprisingly, non-OCD anxiety symptoms did not predict functional impairment (e.g., Angst et al., 2005; Grabe et al., 2000; Storch et al., 2009). This finding was not expected because multiple studies have demonstrated significant associations between these variables (e.g., Angst et al., 2005; Grabe et al., 2000; Storch et al., 2009). It is possible that unique characteristics of the present sample are responsible for the divergent findings as, compared to scores reported for other samples of pediatric OCD (Barrett, Healy-Farrell, & March, 2004; Martin & Thienemann, 2005; ; Storch, Geffken, Merlo, Mann, et al., 2007), non-OCD anxiety scores were low. Alternatively, it may be that non-OCD anxiety does not contribute substantially to functional impairment, over and above OCD symptom severity. With respect to obsessive-compulsive symptom dimensions, only contamination/cleaning and aggressive/checking symptoms were significantly associated with impairment, perhaps because triggers of these symptoms are especially difficult to avoid without compromising daily functioning. When a child has thoughts of cross-contamination, for example, all of the objects in his/her environment may become triggers and the resulting impairment is likely to be pervasive. Interestingly, contamination/cleaning was related to parent-rated impairment in school, home, and social environments but was not related to child-rated impairment in any of these settings. Given previous reports that contamination obsessions and cleaning compulsions are often accommodated by family members (Stewart, Stack, & Wilhelm, 2008), it is possible that children experience these symptoms as minimally impairing because other individuals are compensating for related deficits in functioning. Aggressive/checking symptoms, however, were significantly associated with both parent and child reports of impairment. As compared to other symptom dimensions, these symptoms are perceived by adults with OCD as being particularly ego-dystonic and distressing (Rowa, Purdon, Summerfeldt, & Antony, 2005); to the extent that the same is true for children, it makes sense that the impairment caused by this type of symptom is apparent to youth as well as their parents. Further, aggressive obsessions often involve harm to family members; thus, triggers cannot be avoided without significant disruption to a child’s daily routine. It may also be that such symptoms are quite noticeable to parents, given that youth are likely to seek reassurance and avoid triggers. This study had several limitations. First, because the design was cross-sectional, causal effects could not be inferred. Prospective longitudinal studies are needed to establish the direction of the relationships found significant. Second, the sample was relatively homogeneous demographically, limiting the extent to which findings generalize to the larger population of youth with OCD. Finally, limitations of the instruments available to measure constructs of interest might have affected the results of this study. For example, although the CY-BOCS is currently considered the ‘‘gold standard’’ for assessing symptom severity, scores are based in part on the extent to which obsessions and compulsions interfere with social activities or school performance (which is central to the definition of functional impairment). Thus, relationships between symptom severity and impairment might have been inflated, decreasing the amount of variance explained by adding other variables to regression models. An attempt was made to minimize these differences by using a second measure of symptom severity. Within these limitations, the findings of this study have important implications for clinical practice. First, goals of treatment may need to extend beyond reducing OCD symptom severity in order to address disruption in social, familial, and academic functioning. Recent findings suggest that clinically remitted adults with OCD continue to experience impairments in quality of life and daily living (Huppert et al., 2009). Thus, it may be important for

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interventions to target impacted areas through adjunctive interventions such as academic tutoring, social skills training, or family therapy. Second, treatment for depression might benefit youth who do not have access to front line interventions for OCD as well as nonresponders to OCD treatment by helping them to cope with the consequences of having OCD. Third, findings from this study underscore the importance of addressing family accommodation in treatment. For some children, individual treatment with parental support may be helpful in reducing symptoms; for others – particularly those who receive considerable family accommodation – family-based intervention that targets accommodation may be better suited. It remains unclear if there is an overall difference in treatment efficacy between CBT ‘‘augmented’’ with parental participation versus without. Similar to the non-OCD child anxiety literature (Kendall, Hudson, Gosch, Flannery-Schroeder, & Suveg, 2008), it may be that parental participation is most beneficial with parents who are anxious and/or accommodating. Fourth, the relationship between certain symptom dimensions (i.e., contamination/cleaning and aggressive/checking symptoms) and impairment suggest the importance of considering functionality in future revisions to the DSM-IV-TR. As noted by others (e.g., Storch et al., 2009), the functional relationship between obsessions and compulsions is critical when considering the diagnostic placement of OCD in the DSM-V (i.e., as an anxiety disorder versus in a separate category that may include non-anxiety disorders that are characterized by repetitive behaviors [e.g., gambling]). Obsessive-compulsive disorder involves anxiety linked to obsessions which motivate anxiety-reducing compulsions. This cycle contributes directly to the substantial functional impairment seen in affected individuals; and, this cognitivebehavioral conceptualization is consistent with other anxiety disorders, but differs from disorders characterized by persistent repetitive behaviors in which the repetitive behavior is not anxiety-driven (e.g., gambling or compulsive masturbation is not driven by fear/anxiety). Thus, the present findings lend further support for maintaining OCD as an anxiety disorder in the DSM-V. Finally, with regard to insight, sequential pharmacological treatment may be advised in the context of limited insight particularly since poor insight has been associated with limited CBT response (Storch, Merlo, et al., 2008; Storch, Milsom, et al., 2008). Eisen et al. (2001) showed no differential outcome in sertraline response in adults with OCD with good versus poor insight; degree of insight did not predict pharmacological treatment response. In addition to replicating the current findings and using longitudinal designs to explore temporal relationships among variables, directions for future study include examining additional predictors of impairment (e.g., coping abilities, age of onset of OCD, chronicity). Acknowledgement The contributions of Danielle Bodzin are acknowledged. References Abramowitz, J. S., Storch, E. A., Keeley, M., & Cordell, E. (2007). Obsessive-compulsive disorder with comorbid major depression: what is the role of cognitive factors? Behaviour Research and Therapy, 45, 2257–2267. American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., text revision). Washington, DC: Author. Angst, J., Gamma, A., Endrass, J., Hantouche, E., Goodwin, R., Ajdacic, V., et al. (2005). Obsessive-compulsive syndromes and disorders: significance of comorbidity with bipolar and anxiety syndromes. European Archives of Psychiatry and Clinical Neuroscience, 255, 65–71. Barlow, S. H. (2002). Anxiety and its disorders. The nature and treatment of anxiety and panic second edition. New York, NY: Guilford Press. Barrett, P., Healy-Farrell, L., & March, J. S. (2004). Cognitive-behavioral family treatment of childhood obsessive-compulsive disorder: a controlled trial. Journal of the American Academy of Child and Adolescent Psychiatry, 43, 46–62.

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