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Fixity of belief, perceptual aberration, and magical ideation in obsessive–compulsive disorder
Anxiety Disorders 15 (2001) 501 – 510
Fixity of belief, perceptual aberration, and magical ideation in obsessive–compulsive disorder David F. Tolina,*, Jonathan S. Abramowitzb, Michael J. Kozakc, Edna B. Foad a
Anxiety Disorders Center, The Institute of Living, 200 Retreat Avenue, Hartford, CT 06106, USA b Department of Psychiatry and Psychology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA c Department of Psychiatry, MCP/Hahnemann University, 3200 Henry Avenue, Philadelphia, PA 19129, USA d Department of Psychiatry, University of Pennsylvania, 3535 Market Street, Philadelphia, PA 19104, USA Received 10 January 2000; received in revised form 3 March 2000; accepted 17 March 2000
Abstract Clinicians and researchers have pondered the intersection of obsessive – compulsive disorder (OCD) and psychosis. We examined the records of 395 individuals seeking treatment for OCD and classified participants according to their most frequent or distressing obsession and compulsion. All participants completed measures of fixity of belief, perceptual distortions, magical ideation, and psychotic symptoms. Results indicated that individuals who reported fear of harming self or others via overwhelming impulse or by mistake, and those with religious obsessions, had poorer insight and more perceptual distortions and magical ideation than did individuals with other types of obsessions. These results did not appear to reflect mere differences in OCD severity. Results are discussed in light of previous findings showing that psychotic-like symptoms are associated with attenuated treatment outcome in OCD. More research is needed to assess the absolute magnitude of psychotic-like features in OCD patients with impulse/mistake and religious obsessions and to examine whether these features interfere with standard cognitive – behavioral therapy. D 2001 Elsevier Science Inc. All rights reserved.
* Corresponding author. Tel.: (860)-545-7685; fax: (860)-545-7156. E-mail address: [email protected] (D.F. Tolin). 0887-6185/01/$ – see front matter D 2001 Elsevier Science Inc. All rights reserved. PII: S 0 8 8 7 - 6 1 8 5 ( 0 1 ) 0 0 0 7 8 - 0
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1. Introduction Since the initial reports of obsessive – compulsive disorder (OCD), the similarities between OCD and psychotic disorder have been debated (e.g., Esquirol, 1838, cited in Pollitt, 1956; Westphal, 1878). One traditional view which is reflected in the DSM-III-R (American Psychiatric Association [APA], 1987) holds that patients with OCD recognize their obsessions and compulsions as unreasonable or excessive. Recently, researchers have refocused their attention on features of OCD that overlap with psychosis, and empirical studies lend support to the early clinical observations of overlap between some obsessional thoughts and the formal thought disorder found in the psychotic disorders. For example, Insel and Akiskal (1986) have noted that insight in OCD is distributed over a continuum, ranging from good to poor (see Kozak & Foa, 1994, for a review of this topic). Similarly, in the DSM-IV field trial for OCD, Foa et al. (1995) found that only 25% of patients with OCD firmly believed that no harmful consequences would occur if they did not perform their protective compulsions. The remaining patients were either uncertain about the likelihood of such consequences or were convinced that their fears were valid. This finding led to the inclusion of the subtype ‘‘with poor insight’’ in DSM-IV (APA, 1994). Enright and Beech (1990) have suggested that OCD may have been misclassified as an anxiety disorder and is more accurately conceptualized as a form of schizotypy. In support of this view, Enright (1996) summarized a series of studies suggesting that OCD subjects consistently exhibit schizotypal traits on questionnaires and in cognitive paradigms. The conceptualization of OCD as schizotypy seems unlikely given the relatively low comorbidity between OCD and schizotypal personality disorder (Baer et al., 1990); however, some OCD patients have obsessions that resemble the ideation of psychotic patients in that they are characterized by poor insight into their irrationality, perceptual distortions, suspiciousness, ideas of reference, and magical thinking. This symptom profile has been referred to as ‘‘obsessive compulsive psychosis’’ (Insel & Akiskal, 1986) or ‘‘schizo-obsessive disorder’’ (Jenike, Baer, Minichiello, Schwartz, & Carey, 1986). In order to explore the relationship between OCD and ‘‘psychotic-like’’ symptoms, questionnaires and interviews purporting to measure such symptoms were included in the DSM-IV field trial for OCD (e.g., Foa et al., 1995). As described above, Foa et al. reported that OCD patients showed a range of insight. However, they did not examine whether poor insight was evenly distributed across all categories of obsessions and compulsions. Furthermore, they did not examine the relationship between OCD and other psychotic-like symptoms, e.g., distortions of perception and thought. Such information may have important treatment implications: Several researchers have demonstrated that psychotic-like symptoms are associated with attenuated treatment outcome, presumably because they reduce patients’ willingness and/or ability to engage in exposure and to modify their threat-related beliefs (e.g., Eisen & Rasmussen, 1993; Foa, 1979;
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Foa, Abramowitz, Franklin, & Kozak, 1999; Solyom, Sookman, Solyom, & Morton, 1985). It may be useful to determine whether psychotic-like symptoms are evenly distributed across the range of OCD symptoms, or whether they tend to associate with some symptoms more than with others. The purpose of the present study is to examine the relationship of overvalued ideation, magical ideation, and perceptual aberration with the types of obsessions and compulsions.
2. Method 2.1. Participants Participants were 395 individuals who were recruited for the DSM-IV OCD field trial at seven sites specializing in the treatment and study of OCD (Foa et al., 1995). The sample consisted of English speaking individuals who had either (1) contacted the participating clinics for evaluation or treatment of OCD or (2) were currently involved in treatment for OCD and were still symptomatic. All participants met DSM-III-R (APA, 1987) criteria for primary OCD. Participants were not excluded on the basis of comorbid disorders. Mean age was 35.75 (S.D. = 13.85). Fifty percent of the sample was female. Ninety-two percent were Caucasian, 3% African American, 3% Asian American, and 2% other ethnicity. On the basis of their primary (i.e., most frequently occurring or most distressing) obsession and compulsion as measured by the Yale-Brown Obsessive – Compulsive Scale (Y-BOCS), each participant was assigned to one obsession category and one compulsion category. The proportion of participants in each category is depicted in Table 1. 2.2. Procedure Each patient completed a packet of self-report measures and was then interviewed by a clinician experienced with OCD who was unaware of the present hypotheses. Participants received a standardized assessment of OCD Table 1 Classification of participants according to primary obsession and compulsion (N = 395) Obsessions Impulse/mistake Contamination Sexual Hoarding/saving Religious Symmetry/order Somatic Miscellaneous Total
Compulsions 35% 28% 4% 4% 5% 6% 6% 12% 100%
Washing/cleaning Checking Repeating Counting Ordering/arranging Hoarding/saving Mental compulsions Miscellaneous Total
34% 31% 9% 2% 3% 3% 9% 9% 100%
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symptom severity, the strength of obsessive beliefs, perceptual aberration, magical ideation, and psychotic symptoms. 2.3. Measures 2.3.1. Structured Clinical Interview for DSM-III-R (SCID; Spitzer, Williams, & Gibbon, 1987) The SCID is a standardized interview that was used to determine whether participants met DSM-III-R diagnostic criteria for OCD. The SCID also includes a screening module for psychotic symptoms such as hallucinations and delusions; however, full diagnostic criteria for psychotic disorders were not assessed. Symptoms are coded on the SCID as either present, subclinical, or absent. 2.3.2. Y-BOCS (Goodman, Price, Rasmussen, & Mazure, 1989a, 1989b) The Y-BOCS is an assessor-rated instrument that contains a symptom checklist and a severity scale. The symptom checklist includes a list of 40 obsessions and 29 compulsions, each categorized according to content. Types of obsessions include: (1) impulse/mistake (i.e., harming self or others due to overwhelming impulse or by accident), (2) contamination, (3) sexual, (4) hoarding/saving, (5) religious, (6) symmetry/order, (7) somatic, and (8) miscellaneous obsessions. Categories of compulsions include: (1) cleaning/washing, (2) checking, (3) repeating activities, (4) mental rituals, (5) counting, (6) ordering/ arranging, (7) hoarding/collecting, and (8) miscellaneous compulsions. Patients’ primary obsessions and compulsions were defined. Primacy was defined as the most frequently occurring or most distressing obsession/compulsion. The severity scale of the Y-BOCS contains 10 items: five for obsessions and five for compulsions. Each item is rated on a five-point Likert-type scale (0– 4). Goodman et al. (1989a, 1989b) have reported satisfactory reliability and validity of this widely employed instrument. In the present sample (Foa et al., 1995), interrater agreement for the presence or absence of specific symptom clusters ranged from 77% to 100%, and k coefficients were moderate to high (r = .55 –.88) with the exception of sexual obsessions (r = .35), somatic obsessions (r = .46), and mental rituals (r = .46). The intraclass correlation coefficient for the Y-BOCS total score was .63. 2.3.3. Fixity of Beliefs Questionnaire (FBQ; Foa et al., 1995) The FBQ is a group of seven interview questions designed to measure the degree to which individuals with OCD recognize that their beliefs are unreasonable. Scales on the FBQ are rated from 0 to 4. The first item assesses the feared outcome for the most interfering or distressing obsession. Choices include: (a) a specific outcome, (b) becoming extremely anxious but no other consequence, (c) increased ritualizing but no other consequence, or (d) no consequence. Participants who identify a specific feared consequence are then rated on six additional items measuring the strength of belief that the fear is
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reasonable or rational. Foa et al. (1999) found that two items, presence of feared consequences and certainty that the feared consequence will occur, predict treatment outcome for OCD. Patients with a feared consequence were twice as likely to show clinically significant response than were those with no feared consequence, whereas those with high certainty that the belief would occur had 20% less reduction on the Y-BOCS than did those with low certainty. In the present sample (Foa et al., 1995), interrater reliability for most FBQ items was moderate (r = .42 –.80 with 62– 96% agreement), with the exception of bizarreness of the belief (r = .11, 29% agreement). 2.3.4. Magical Ideation Scale (MIS; Eckblad & Chapman, 1983) The MIS is a 30-item true/false scale measuring belief in forms of causation that by conventional standards are invalid. Examples of MIS items are: ‘‘I have felt that there were messages for me in the way things were arranged, like in a store window’’ (keyed true) and ‘‘It is not possible to harm others merely by thinking bad thoughts about them’’ (keyed false). Internal consistency coefficients for the MIS ranged from .82 to .85. The MIS correlated moderately with the Perceptual Aberration Scale (PAS), and individuals with high MIS scores are disproportionately more likely than those with low scores to meet diagnostic criteria for mood, personality, and psychotic disorders (Eckblad & Chapman, 1983). 2.3.5. PAS (Chapman, Edell, & Chapman, 1980) The PAS is a 65-item true/false scale designed to measure major distortions in the perception of one’s surroundings and one’s own body. Sample PAS items are: ‘‘Sometimes I have felt that I could not distinguish my body from other objects around me’’ (keyed true) and ‘‘My hands or feet have never seemed far away’’ (keyed false). Individuals with high PAS scores report a greater number of psychotic symptoms than do normal subjects or anhedonic subjects with low PAS scores; furthermore, high PAS individuals are disproportionately more likely to meet criteria for schizotypal personality and mood disorders (Chapman et al., 1980).
3. Results Kolmogoroff – Smirnov tests indicated that distributions of scores for all measures were highly positively skewed. Therefore, nonparametric tests were used. 3.1. Fixity of beliefs The first item on the FBQ assesses the most feared consequence of the primary obsession. Sixty percent of participants were able to identify a disastrous consequence that they feared would happen if they did not perform their compulsions. The remaining 40% either could not identify such a consequence or stated that the only consequence would be increased distress or ritualizing. A
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significant 2 (Feared Consequence vs. No Feared Consequence) 8 (Obsession Category) chi-square analysis indicated that the presence of feared consequences was not evenly distributed across obsession categories, c2(7) = 47.18, P < .001. Inspection of standardized residuals and cell frequencies indicated that individuals with primary impulse/mistake obsessions were more likely to identify a feared consequence (80.4%) than were individuals with primary hoarding and ‘‘miscellaneous’’ obsessions (30.8% and 39.6%, respectively). The parallel analysis for compulsion categories was not significant, c2(7) = 13.40, P > .05. To examine whether degree of fixity of belief for the primary obsession differed across the various obsession and compulsion categories, medians and standard deviations of the total fixity of belief scores (for those participants who identified a feared consequence) were calculated separately for each obsession and compulsion category. They are presented in Table 2. These medians were submitted to two Kruskal – Wallis tests, one for obsessions and one for compulsions. The test for the obsession categories was significant, c2(7) = 29.56, P < .01. Post hoc Mann – Whitney U tests indicated that individuals with primary impulse/mistake obsessions had greater fixity of belief than did those with primary contamination, hoarding, symmetry/order, somatic, and ‘‘miscellaneous’’ obsessions. Furthermore, individuals with primary religious obsessions had greater fixity of belief than did individuals with primary contamination, hoarding, symmetry/order, somatic, and ‘‘miscellaneous’’ obsessions (all P’s < .05). The analysis for the compulsion categories was not significant, P > .05. Individuals with high and low fixity of beliefs (based on a median split) did not differ in Y-BOCS severity (all P’s > .05). Thus, the obtained between-group differences do not appear to be attributable merely to severity of OCD symptoms. 3.2. Perceptual aberration To determine whether individuals with different primary obsessions and compulsions varied in perceptual aberration, we calculated medians and standard deviations for the eight obsession and compulsion categories (see Table 2). Two Kruskal –Wallis analyses of PAS total score were performed, separately for the Table 2 Median (S.D.) PBQ, PAS, and MIS scores by obsession category FBQ Obsession category Impulse/mistake Contamination Sexual Hoarding/saving Religious Symmetry/order Somatic Miscellaneous
4.00 1.00 2.00 0.00 6.00 0.00 0.00 0.00
PAS (4.02) (4.16) (4.25) (4.38) (5.00) (4.26) (3.72) (3.67)
1.00 0.00 0.00 1.00 3.00 0.00 1.00 1.00
MIS (5.57) (3.99) (2.42) (3.09) (4.11) (4.28) (2.73) (6.05)
3.00 2.00 2.00 3.00 4.00 2.00 1.00 2.00
(3.92) (3.28) (2.50) (4.31) (2.91) (2.77) (1.36) (3.74)
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obsession and the compulsion categories. The analysis for obsession category was significant, c2(7) = 15.88, P < .05. Mann – Whitney U tests indicated that participants with primary impulse/mistake obsessions reported greater perceptual aberration than did individuals with primary contamination and symmetry/order obsessions. Furthermore, individuals with primary religious and ‘‘miscellaneous’’ obsessions scored higher than did individuals with primary contamination obsessions (all P’s < .05). The Kruskal –Wallis analysis for compulsion category was not significant, P > .05. As was found with the FBQ, individuals with high and low perceptual aberration (as determined by a median split) did not differ in Y-BOCS severity (all P’s > .05). Thus, the obtained differences in perceptual aberration do not seem merely to reflect differences in OCD severity. 3.3. Magical ideation To examine whether magical ideation aggregated differently according to obsessions and compulsions, we calculated the medians and standard deviation of MIS total for the obsession and compulsion categories (see Table 2). We then performed two Kruskal – Wallis analyses, separately for the obsession and compulsion categories. The analysis for obsession category was significant, c2(7) = 24.82, P < .01. Mann –Whitney U tests indicated that individuals with primary impulse/mistake and religious obsessions had greater magical ideation than did those with primary contamination, symmetry/order, and somatic obsessions (all P’s < .05). The analysis of MIS total score by compulsion group was not significant, P > .05. Individuals with high and low magical ideation (as determined by median split) did not differ in terms of Y-BOCS severity (all P’s > .05), indicating that the obtained differences in magical ideation are not due solely to differences in OCD severity. To determine whether certain MIS items that overlap with OCD symptoms (e.g., ‘‘At times I perform certain little rituals to ward off negative influences’’) were responsible for the obtained results, we examined betweengroup differences for each item. Results of this inspection suggested that no single item or cluster of items was responsible for the obtained difference. 3.4. Psychotic screen Next, we examined whether individuals with certain OCD symptoms were more likely than others to endorse symptoms of psychotic disorders according to the SCID. For this analysis, individuals were divided into a ‘‘psychotic symptom’’ group (N = 34) if they responded ‘‘yes’’ to one or more items on the SCID psychotic screen, or to a ‘‘no psychotic symptom’’ group (N = 374) if they denied any psychotic symptoms on the SCID. For both obsessions and compulsions, Psychotic Symptom Group OCD Group chi-square analyses were not significant, P > .05.
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4. Discussion Results of the present study extend previous findings (e.g., Foa et al., 1995) by demonstrating that psychotic-like symptoms such as fixity of belief, perceptual aberration, and magical ideation are more likely to occur in conjunction with some OCD concerns than with others. The most consistently obtained results, and therefore those in which the greatest confidence should be placed, showed that individuals with impulse/mistake and religious obsessions exhibit somewhat higher fixity of belief, perceptual aberration, and magical ideation than do individuals with contamination and symmetry obsessions. Although the present data shed light on the relative levels of psychotic-like symptoms between OCD subtypes, they provide little information about the absolute levels compared to nonpatient samples. The original normative studies of the MIS and PAS (Chapman et al., 1980; Eckblad & Chapman, 1983) yielded highly skewed distributions, with means that were undoubtedly influenced by extreme scores. In the present study we examined sample medians rather than means. This method provides a more accurate representation of the sample; however, it is inappropriate to compare these medians to the means of other samples. As a result, discussion of the practical relevance of the present data is speculative. It might be argued that the differences between OCD subtypes are statistically significant, but not clinically so. Alternatively, examination of the item content of the FBQ (e.g., ‘‘Patient believes self to possess a special knowledge that others don’t have’’), MIS (e.g., ‘‘I have sometimes felt that strangers were reading my mind’’), and PAS (e.g., ‘‘Occasionally I have felt as thought my body did not exist’’) suggests that endorsement of only a few items may nonetheless indicate clinically significant disturbance. Future studies should include a nonpatient sample in order to assess this issue further; in addition, external validation using other standardized measures of thought disorder is desirable. In the present sample, type of compulsion showed fewer significant relationships with psychotic-like symptoms than did type of obsession. The only significant relationship concerning compulsions was found with magical ideation, where individuals with repeating, counting, and hoarding compulsions exhibited higher scores than did those with other types of compulsions. Because the association between psychotic-like symptoms and obsessions is stronger than that with compulsions, classifications according to compulsions only (e.g., ‘‘washers’’ vs. ‘‘checkers’’) may not adequately predict psychotic-like symptoms. Rather, it appears that certain obsessions are likely to be held very firmly, and are likely to be associated with other forms of illogical thought and distorted perception. One limitation of the present study is that only the psychotic screening module of the SCID was used, rather than the entire psychotic disorders module. Individual psychotic symptoms may or may not indicate the presence of a psychotic disorder such as schizophrenia. As a result, one cannot determine the prevalence of formal
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psychotic disorders among the different OCD subtypes. Future studies should include a more thorough assessment of comorbid psychotic disorders. Another limitation is the fact that the present patients were diagnosed using DSM-III-R rather than DSM-IV criteria (the patients were participants in the DSM-IV field trial). As described by Foa et al. (1995), the primary distinction between the two sets of criteria is the addition of the subtype ‘‘with poor insight’’ in DSM-IV. In DSM-III-R, it was assumed that patients had insight into the senselessness of their symptoms. In the present sample, Foa et al. reported that patients with poor insight were still diagnosed with OCD; thus, the present sample appears to satisfy DSM-IV criteria as well. Nevertheless, replication using patients specifically diagnosed according to DSM-IV may be desirable, especially for patients meeting criteria for the ‘‘poor insight’’ subtype. The present data suggest that in clinical samples, OCD patients with impulse/mistake and religious obsessions may be more likely than other patients to experience poor insight and disturbances of perception and thought. Given the earlier treatment outcome data (e.g., Eisen & Rasmussen, 1993; Foa, 1979; Foa et al., 1999; Solyom et al., 1985), one might expect such patients to present a particular challenge to cognitive – behavioral therapists. However, other investigators have reported that psychotic-like symptoms do not impede treatment response (e.g., Basoglu, Lax, Kasvikis, & Marks, 1988; Lelliott & Marks, 1987). Thus, it would be premature to infer from the present results that patients with impulse/mistake and religious obsessions will benefit less from Cognitive-behavioral Therapy (CBT). More research is needed to examine whether OCD subtype and psychotic-like symptoms are related to outcome, and if so, whether concomitant treatment approaches that directly address psychotic-like symptoms can be helpful. Furthermore, additional research is needed to clarify the relationship between psychotic-like symptoms (e.g., poor insight) and outcome. One possibility is that studies showing a relationship included participants with extreme scores on the predictor variables, whereas studies showing no relationship used linear methods that are insensitive to nonlinear effects, or failed to survey an adequate sample of individuals with extreme scores. Future researchers should take care to obtain adequate samples of individuals with a broad range of psychotic-like symptom severity, and to explore the possibility that nonlinear relationships may exist between such symptoms and outcome (e.g., outcome may be attenuated only for those patients with extremely high levels of psychotic-like symptoms).
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American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (fourth ed.). Washington, DC: American Psychiatric Association. Baer, L., Jenike, M. A., Ricciardi, J. N., Holland, A. D., Seymour, R. J., Minichiello, W. E., & Buttolph, M. L. (1990). Standardized assessment of personality disorders in obsessive – compulsive disorder. Archives of General Psychiatry, 47, 826 – 830. Basoglu, M., Lax, T., Kasvikis, Y., & Marks, I. M. (1988). Predictors of improvement in obsessive – compulsive disorder. Journal of Anxiety Disorders, 2, 299 – 317. Chapman, L. J., Edell, W. S., & Chapman, J. P. (1980). Physical anhedonia, perceptual aberration, and psychosis proneness. Schizophrenia Bulletin, 6, 639 – 653. Eckblad, M., & Chapman, L. J. (1983). Magical ideation as an indicator of schizotypy. Journal of Consulting and Clinical Psychology, 51, 215 – 225. Eisen, J. L., & Rasmussen, S. A. (1993). Obsessive – compulsive disorder with psychotic features. Journal of Clinical Psychiatry, 54, 373 – 379. Enright, S. J. (1996). Obsessive – compulsive disorder: anxiety disorder or schizotype? In: R. M. Rapee (Ed.), Current controversies in the anxiety disorders ( pp. 161 – 190). New York: Guilford. Enright, S. J., & Beech, A. R. (1990). Obsessional states: anxiety disorders or schizotypes? An information processing and personality assessment. Psychological Medicine, 20, 621 – 627. Foa, E. B. (1979). Failures in treating obsessive – compulsives. Behaviour Research and Therapy, 17, 169 – 176. Foa, E. B., Abramowitz, J. S., Franklin, M. E., & Kozak, M. J. (1999). Feared consequences, fixity of belief, and treatment outcome in patients with obsessive – compulsive disorder. Behavior Therapy, 30, 717 – 724. Foa, E. B., Kozak, M. J., Goodman, W. K., Jenike, M. A., Hollander, E., & Rasmussen, S. (1995). DSM IV field trial: obsessive – compulsive disorder. American Journal of Psychiatry, 152, 90 – 96. Goodman, W. K., Price, L. H., Rasmussen, S. A., & Mazure, C. (1989a). The Yale-Brown Obsessive – Compulsive Scale (Y-BOCS): development, use, reliability. Archives of General Psychiatry, 46, 1006 – 1011. Goodman, W. K., Price, L. H., Rasmussen, S. A., & Mazure, C. (1989b). The Yale-Brown Obsessive – Compulsive Scale (Y-BOCS): validity. Archives of General Psychiatry, 46, 1012 – 1016. Insel, T. R., & Akiskal, H. S. (1986). Obsessive – compulsive disorder with psychotic features: a phenomenological analysis. American Journal of Psychiatry, 143, 1527 – 1533. Jenike, M. A., Baer, L., Minichiello, W. E., Schwartz, C. E., & Carey, R. J. (1986). Concomitant obsessive – compulsive personality disorder and schizotypal personality disorder. American Journal of Psychiatry, 143, 530 – 532. Kozak, M. J., & Foa, E. B. (1994). Obsessions, overvalued ideas, and delusions in obsessive – compulsive disorder. Behaviour Research and Therapy, 32, 343 – 353. Lelliott, P., & Marks, I. M. (1987). Management of obsessive – compulsive rituals associated with delusions, hallucinations and depression: a case report. Behavioural Psychotherapy, 15, 77 – 87. Pollitt, J. (1956). Discussion: obsessive – compulsive states (abridged). Proceedings of the Royal Society of Medicine, 49, 842 – 845. Solyom, L., Sookman, D., Solyom, C., & Morton, L. (1985). Behavior therapy versus drug therapy in the treatment of obsessional illness. Unpublished manuscript. Spitzer, R. L., Williams, J. W. B., & Gibbon, M. (1987). Structured Clinical Interview for DSM-III-R. New York: New York State Psychiatric Institute. Westphal, K. (1878). Uber Zwangsvortellungen. Archiv fu¨r Psychiatrie und Nervenkranken, 8, 734 – 750.
Fixity of belief, perceptual aberration, and magical ideation in obsessive–compulsive disorder David F. Tolina,*, Jonathan S. Abramowitzb, Michael J. Kozakc, Edna B. Foad a
Anxiety Disorders Center, The Institute of Living, 200 Retreat Avenue, Hartford, CT 06106, USA b Department of Psychiatry and Psychology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA c Department of Psychiatry, MCP/Hahnemann University, 3200 Henry Avenue, Philadelphia, PA 19129, USA d Department of Psychiatry, University of Pennsylvania, 3535 Market Street, Philadelphia, PA 19104, USA Received 10 January 2000; received in revised form 3 March 2000; accepted 17 March 2000
Abstract Clinicians and researchers have pondered the intersection of obsessive – compulsive disorder (OCD) and psychosis. We examined the records of 395 individuals seeking treatment for OCD and classified participants according to their most frequent or distressing obsession and compulsion. All participants completed measures of fixity of belief, perceptual distortions, magical ideation, and psychotic symptoms. Results indicated that individuals who reported fear of harming self or others via overwhelming impulse or by mistake, and those with religious obsessions, had poorer insight and more perceptual distortions and magical ideation than did individuals with other types of obsessions. These results did not appear to reflect mere differences in OCD severity. Results are discussed in light of previous findings showing that psychotic-like symptoms are associated with attenuated treatment outcome in OCD. More research is needed to assess the absolute magnitude of psychotic-like features in OCD patients with impulse/mistake and religious obsessions and to examine whether these features interfere with standard cognitive – behavioral therapy. D 2001 Elsevier Science Inc. All rights reserved.
* Corresponding author. Tel.: (860)-545-7685; fax: (860)-545-7156. E-mail address: [email protected] (D.F. Tolin). 0887-6185/01/$ – see front matter D 2001 Elsevier Science Inc. All rights reserved. PII: S 0 8 8 7 - 6 1 8 5 ( 0 1 ) 0 0 0 7 8 - 0
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1. Introduction Since the initial reports of obsessive – compulsive disorder (OCD), the similarities between OCD and psychotic disorder have been debated (e.g., Esquirol, 1838, cited in Pollitt, 1956; Westphal, 1878). One traditional view which is reflected in the DSM-III-R (American Psychiatric Association [APA], 1987) holds that patients with OCD recognize their obsessions and compulsions as unreasonable or excessive. Recently, researchers have refocused their attention on features of OCD that overlap with psychosis, and empirical studies lend support to the early clinical observations of overlap between some obsessional thoughts and the formal thought disorder found in the psychotic disorders. For example, Insel and Akiskal (1986) have noted that insight in OCD is distributed over a continuum, ranging from good to poor (see Kozak & Foa, 1994, for a review of this topic). Similarly, in the DSM-IV field trial for OCD, Foa et al. (1995) found that only 25% of patients with OCD firmly believed that no harmful consequences would occur if they did not perform their protective compulsions. The remaining patients were either uncertain about the likelihood of such consequences or were convinced that their fears were valid. This finding led to the inclusion of the subtype ‘‘with poor insight’’ in DSM-IV (APA, 1994). Enright and Beech (1990) have suggested that OCD may have been misclassified as an anxiety disorder and is more accurately conceptualized as a form of schizotypy. In support of this view, Enright (1996) summarized a series of studies suggesting that OCD subjects consistently exhibit schizotypal traits on questionnaires and in cognitive paradigms. The conceptualization of OCD as schizotypy seems unlikely given the relatively low comorbidity between OCD and schizotypal personality disorder (Baer et al., 1990); however, some OCD patients have obsessions that resemble the ideation of psychotic patients in that they are characterized by poor insight into their irrationality, perceptual distortions, suspiciousness, ideas of reference, and magical thinking. This symptom profile has been referred to as ‘‘obsessive compulsive psychosis’’ (Insel & Akiskal, 1986) or ‘‘schizo-obsessive disorder’’ (Jenike, Baer, Minichiello, Schwartz, & Carey, 1986). In order to explore the relationship between OCD and ‘‘psychotic-like’’ symptoms, questionnaires and interviews purporting to measure such symptoms were included in the DSM-IV field trial for OCD (e.g., Foa et al., 1995). As described above, Foa et al. reported that OCD patients showed a range of insight. However, they did not examine whether poor insight was evenly distributed across all categories of obsessions and compulsions. Furthermore, they did not examine the relationship between OCD and other psychotic-like symptoms, e.g., distortions of perception and thought. Such information may have important treatment implications: Several researchers have demonstrated that psychotic-like symptoms are associated with attenuated treatment outcome, presumably because they reduce patients’ willingness and/or ability to engage in exposure and to modify their threat-related beliefs (e.g., Eisen & Rasmussen, 1993; Foa, 1979;
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Foa, Abramowitz, Franklin, & Kozak, 1999; Solyom, Sookman, Solyom, & Morton, 1985). It may be useful to determine whether psychotic-like symptoms are evenly distributed across the range of OCD symptoms, or whether they tend to associate with some symptoms more than with others. The purpose of the present study is to examine the relationship of overvalued ideation, magical ideation, and perceptual aberration with the types of obsessions and compulsions.
2. Method 2.1. Participants Participants were 395 individuals who were recruited for the DSM-IV OCD field trial at seven sites specializing in the treatment and study of OCD (Foa et al., 1995). The sample consisted of English speaking individuals who had either (1) contacted the participating clinics for evaluation or treatment of OCD or (2) were currently involved in treatment for OCD and were still symptomatic. All participants met DSM-III-R (APA, 1987) criteria for primary OCD. Participants were not excluded on the basis of comorbid disorders. Mean age was 35.75 (S.D. = 13.85). Fifty percent of the sample was female. Ninety-two percent were Caucasian, 3% African American, 3% Asian American, and 2% other ethnicity. On the basis of their primary (i.e., most frequently occurring or most distressing) obsession and compulsion as measured by the Yale-Brown Obsessive – Compulsive Scale (Y-BOCS), each participant was assigned to one obsession category and one compulsion category. The proportion of participants in each category is depicted in Table 1. 2.2. Procedure Each patient completed a packet of self-report measures and was then interviewed by a clinician experienced with OCD who was unaware of the present hypotheses. Participants received a standardized assessment of OCD Table 1 Classification of participants according to primary obsession and compulsion (N = 395) Obsessions Impulse/mistake Contamination Sexual Hoarding/saving Religious Symmetry/order Somatic Miscellaneous Total
Compulsions 35% 28% 4% 4% 5% 6% 6% 12% 100%
Washing/cleaning Checking Repeating Counting Ordering/arranging Hoarding/saving Mental compulsions Miscellaneous Total
34% 31% 9% 2% 3% 3% 9% 9% 100%
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symptom severity, the strength of obsessive beliefs, perceptual aberration, magical ideation, and psychotic symptoms. 2.3. Measures 2.3.1. Structured Clinical Interview for DSM-III-R (SCID; Spitzer, Williams, & Gibbon, 1987) The SCID is a standardized interview that was used to determine whether participants met DSM-III-R diagnostic criteria for OCD. The SCID also includes a screening module for psychotic symptoms such as hallucinations and delusions; however, full diagnostic criteria for psychotic disorders were not assessed. Symptoms are coded on the SCID as either present, subclinical, or absent. 2.3.2. Y-BOCS (Goodman, Price, Rasmussen, & Mazure, 1989a, 1989b) The Y-BOCS is an assessor-rated instrument that contains a symptom checklist and a severity scale. The symptom checklist includes a list of 40 obsessions and 29 compulsions, each categorized according to content. Types of obsessions include: (1) impulse/mistake (i.e., harming self or others due to overwhelming impulse or by accident), (2) contamination, (3) sexual, (4) hoarding/saving, (5) religious, (6) symmetry/order, (7) somatic, and (8) miscellaneous obsessions. Categories of compulsions include: (1) cleaning/washing, (2) checking, (3) repeating activities, (4) mental rituals, (5) counting, (6) ordering/ arranging, (7) hoarding/collecting, and (8) miscellaneous compulsions. Patients’ primary obsessions and compulsions were defined. Primacy was defined as the most frequently occurring or most distressing obsession/compulsion. The severity scale of the Y-BOCS contains 10 items: five for obsessions and five for compulsions. Each item is rated on a five-point Likert-type scale (0– 4). Goodman et al. (1989a, 1989b) have reported satisfactory reliability and validity of this widely employed instrument. In the present sample (Foa et al., 1995), interrater agreement for the presence or absence of specific symptom clusters ranged from 77% to 100%, and k coefficients were moderate to high (r = .55 –.88) with the exception of sexual obsessions (r = .35), somatic obsessions (r = .46), and mental rituals (r = .46). The intraclass correlation coefficient for the Y-BOCS total score was .63. 2.3.3. Fixity of Beliefs Questionnaire (FBQ; Foa et al., 1995) The FBQ is a group of seven interview questions designed to measure the degree to which individuals with OCD recognize that their beliefs are unreasonable. Scales on the FBQ are rated from 0 to 4. The first item assesses the feared outcome for the most interfering or distressing obsession. Choices include: (a) a specific outcome, (b) becoming extremely anxious but no other consequence, (c) increased ritualizing but no other consequence, or (d) no consequence. Participants who identify a specific feared consequence are then rated on six additional items measuring the strength of belief that the fear is
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reasonable or rational. Foa et al. (1999) found that two items, presence of feared consequences and certainty that the feared consequence will occur, predict treatment outcome for OCD. Patients with a feared consequence were twice as likely to show clinically significant response than were those with no feared consequence, whereas those with high certainty that the belief would occur had 20% less reduction on the Y-BOCS than did those with low certainty. In the present sample (Foa et al., 1995), interrater reliability for most FBQ items was moderate (r = .42 –.80 with 62– 96% agreement), with the exception of bizarreness of the belief (r = .11, 29% agreement). 2.3.4. Magical Ideation Scale (MIS; Eckblad & Chapman, 1983) The MIS is a 30-item true/false scale measuring belief in forms of causation that by conventional standards are invalid. Examples of MIS items are: ‘‘I have felt that there were messages for me in the way things were arranged, like in a store window’’ (keyed true) and ‘‘It is not possible to harm others merely by thinking bad thoughts about them’’ (keyed false). Internal consistency coefficients for the MIS ranged from .82 to .85. The MIS correlated moderately with the Perceptual Aberration Scale (PAS), and individuals with high MIS scores are disproportionately more likely than those with low scores to meet diagnostic criteria for mood, personality, and psychotic disorders (Eckblad & Chapman, 1983). 2.3.5. PAS (Chapman, Edell, & Chapman, 1980) The PAS is a 65-item true/false scale designed to measure major distortions in the perception of one’s surroundings and one’s own body. Sample PAS items are: ‘‘Sometimes I have felt that I could not distinguish my body from other objects around me’’ (keyed true) and ‘‘My hands or feet have never seemed far away’’ (keyed false). Individuals with high PAS scores report a greater number of psychotic symptoms than do normal subjects or anhedonic subjects with low PAS scores; furthermore, high PAS individuals are disproportionately more likely to meet criteria for schizotypal personality and mood disorders (Chapman et al., 1980).
3. Results Kolmogoroff – Smirnov tests indicated that distributions of scores for all measures were highly positively skewed. Therefore, nonparametric tests were used. 3.1. Fixity of beliefs The first item on the FBQ assesses the most feared consequence of the primary obsession. Sixty percent of participants were able to identify a disastrous consequence that they feared would happen if they did not perform their compulsions. The remaining 40% either could not identify such a consequence or stated that the only consequence would be increased distress or ritualizing. A
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significant 2 (Feared Consequence vs. No Feared Consequence) 8 (Obsession Category) chi-square analysis indicated that the presence of feared consequences was not evenly distributed across obsession categories, c2(7) = 47.18, P < .001. Inspection of standardized residuals and cell frequencies indicated that individuals with primary impulse/mistake obsessions were more likely to identify a feared consequence (80.4%) than were individuals with primary hoarding and ‘‘miscellaneous’’ obsessions (30.8% and 39.6%, respectively). The parallel analysis for compulsion categories was not significant, c2(7) = 13.40, P > .05. To examine whether degree of fixity of belief for the primary obsession differed across the various obsession and compulsion categories, medians and standard deviations of the total fixity of belief scores (for those participants who identified a feared consequence) were calculated separately for each obsession and compulsion category. They are presented in Table 2. These medians were submitted to two Kruskal – Wallis tests, one for obsessions and one for compulsions. The test for the obsession categories was significant, c2(7) = 29.56, P < .01. Post hoc Mann – Whitney U tests indicated that individuals with primary impulse/mistake obsessions had greater fixity of belief than did those with primary contamination, hoarding, symmetry/order, somatic, and ‘‘miscellaneous’’ obsessions. Furthermore, individuals with primary religious obsessions had greater fixity of belief than did individuals with primary contamination, hoarding, symmetry/order, somatic, and ‘‘miscellaneous’’ obsessions (all P’s < .05). The analysis for the compulsion categories was not significant, P > .05. Individuals with high and low fixity of beliefs (based on a median split) did not differ in Y-BOCS severity (all P’s > .05). Thus, the obtained between-group differences do not appear to be attributable merely to severity of OCD symptoms. 3.2. Perceptual aberration To determine whether individuals with different primary obsessions and compulsions varied in perceptual aberration, we calculated medians and standard deviations for the eight obsession and compulsion categories (see Table 2). Two Kruskal –Wallis analyses of PAS total score were performed, separately for the Table 2 Median (S.D.) PBQ, PAS, and MIS scores by obsession category FBQ Obsession category Impulse/mistake Contamination Sexual Hoarding/saving Religious Symmetry/order Somatic Miscellaneous
4.00 1.00 2.00 0.00 6.00 0.00 0.00 0.00
PAS (4.02) (4.16) (4.25) (4.38) (5.00) (4.26) (3.72) (3.67)
1.00 0.00 0.00 1.00 3.00 0.00 1.00 1.00
MIS (5.57) (3.99) (2.42) (3.09) (4.11) (4.28) (2.73) (6.05)
3.00 2.00 2.00 3.00 4.00 2.00 1.00 2.00
(3.92) (3.28) (2.50) (4.31) (2.91) (2.77) (1.36) (3.74)
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obsession and the compulsion categories. The analysis for obsession category was significant, c2(7) = 15.88, P < .05. Mann – Whitney U tests indicated that participants with primary impulse/mistake obsessions reported greater perceptual aberration than did individuals with primary contamination and symmetry/order obsessions. Furthermore, individuals with primary religious and ‘‘miscellaneous’’ obsessions scored higher than did individuals with primary contamination obsessions (all P’s < .05). The Kruskal –Wallis analysis for compulsion category was not significant, P > .05. As was found with the FBQ, individuals with high and low perceptual aberration (as determined by a median split) did not differ in Y-BOCS severity (all P’s > .05). Thus, the obtained differences in perceptual aberration do not seem merely to reflect differences in OCD severity. 3.3. Magical ideation To examine whether magical ideation aggregated differently according to obsessions and compulsions, we calculated the medians and standard deviation of MIS total for the obsession and compulsion categories (see Table 2). We then performed two Kruskal – Wallis analyses, separately for the obsession and compulsion categories. The analysis for obsession category was significant, c2(7) = 24.82, P < .01. Mann –Whitney U tests indicated that individuals with primary impulse/mistake and religious obsessions had greater magical ideation than did those with primary contamination, symmetry/order, and somatic obsessions (all P’s < .05). The analysis of MIS total score by compulsion group was not significant, P > .05. Individuals with high and low magical ideation (as determined by median split) did not differ in terms of Y-BOCS severity (all P’s > .05), indicating that the obtained differences in magical ideation are not due solely to differences in OCD severity. To determine whether certain MIS items that overlap with OCD symptoms (e.g., ‘‘At times I perform certain little rituals to ward off negative influences’’) were responsible for the obtained results, we examined betweengroup differences for each item. Results of this inspection suggested that no single item or cluster of items was responsible for the obtained difference. 3.4. Psychotic screen Next, we examined whether individuals with certain OCD symptoms were more likely than others to endorse symptoms of psychotic disorders according to the SCID. For this analysis, individuals were divided into a ‘‘psychotic symptom’’ group (N = 34) if they responded ‘‘yes’’ to one or more items on the SCID psychotic screen, or to a ‘‘no psychotic symptom’’ group (N = 374) if they denied any psychotic symptoms on the SCID. For both obsessions and compulsions, Psychotic Symptom Group OCD Group chi-square analyses were not significant, P > .05.
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4. Discussion Results of the present study extend previous findings (e.g., Foa et al., 1995) by demonstrating that psychotic-like symptoms such as fixity of belief, perceptual aberration, and magical ideation are more likely to occur in conjunction with some OCD concerns than with others. The most consistently obtained results, and therefore those in which the greatest confidence should be placed, showed that individuals with impulse/mistake and religious obsessions exhibit somewhat higher fixity of belief, perceptual aberration, and magical ideation than do individuals with contamination and symmetry obsessions. Although the present data shed light on the relative levels of psychotic-like symptoms between OCD subtypes, they provide little information about the absolute levels compared to nonpatient samples. The original normative studies of the MIS and PAS (Chapman et al., 1980; Eckblad & Chapman, 1983) yielded highly skewed distributions, with means that were undoubtedly influenced by extreme scores. In the present study we examined sample medians rather than means. This method provides a more accurate representation of the sample; however, it is inappropriate to compare these medians to the means of other samples. As a result, discussion of the practical relevance of the present data is speculative. It might be argued that the differences between OCD subtypes are statistically significant, but not clinically so. Alternatively, examination of the item content of the FBQ (e.g., ‘‘Patient believes self to possess a special knowledge that others don’t have’’), MIS (e.g., ‘‘I have sometimes felt that strangers were reading my mind’’), and PAS (e.g., ‘‘Occasionally I have felt as thought my body did not exist’’) suggests that endorsement of only a few items may nonetheless indicate clinically significant disturbance. Future studies should include a nonpatient sample in order to assess this issue further; in addition, external validation using other standardized measures of thought disorder is desirable. In the present sample, type of compulsion showed fewer significant relationships with psychotic-like symptoms than did type of obsession. The only significant relationship concerning compulsions was found with magical ideation, where individuals with repeating, counting, and hoarding compulsions exhibited higher scores than did those with other types of compulsions. Because the association between psychotic-like symptoms and obsessions is stronger than that with compulsions, classifications according to compulsions only (e.g., ‘‘washers’’ vs. ‘‘checkers’’) may not adequately predict psychotic-like symptoms. Rather, it appears that certain obsessions are likely to be held very firmly, and are likely to be associated with other forms of illogical thought and distorted perception. One limitation of the present study is that only the psychotic screening module of the SCID was used, rather than the entire psychotic disorders module. Individual psychotic symptoms may or may not indicate the presence of a psychotic disorder such as schizophrenia. As a result, one cannot determine the prevalence of formal
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psychotic disorders among the different OCD subtypes. Future studies should include a more thorough assessment of comorbid psychotic disorders. Another limitation is the fact that the present patients were diagnosed using DSM-III-R rather than DSM-IV criteria (the patients were participants in the DSM-IV field trial). As described by Foa et al. (1995), the primary distinction between the two sets of criteria is the addition of the subtype ‘‘with poor insight’’ in DSM-IV. In DSM-III-R, it was assumed that patients had insight into the senselessness of their symptoms. In the present sample, Foa et al. reported that patients with poor insight were still diagnosed with OCD; thus, the present sample appears to satisfy DSM-IV criteria as well. Nevertheless, replication using patients specifically diagnosed according to DSM-IV may be desirable, especially for patients meeting criteria for the ‘‘poor insight’’ subtype. The present data suggest that in clinical samples, OCD patients with impulse/mistake and religious obsessions may be more likely than other patients to experience poor insight and disturbances of perception and thought. Given the earlier treatment outcome data (e.g., Eisen & Rasmussen, 1993; Foa, 1979; Foa et al., 1999; Solyom et al., 1985), one might expect such patients to present a particular challenge to cognitive – behavioral therapists. However, other investigators have reported that psychotic-like symptoms do not impede treatment response (e.g., Basoglu, Lax, Kasvikis, & Marks, 1988; Lelliott & Marks, 1987). Thus, it would be premature to infer from the present results that patients with impulse/mistake and religious obsessions will benefit less from Cognitive-behavioral Therapy (CBT). More research is needed to examine whether OCD subtype and psychotic-like symptoms are related to outcome, and if so, whether concomitant treatment approaches that directly address psychotic-like symptoms can be helpful. Furthermore, additional research is needed to clarify the relationship between psychotic-like symptoms (e.g., poor insight) and outcome. One possibility is that studies showing a relationship included participants with extreme scores on the predictor variables, whereas studies showing no relationship used linear methods that are insensitive to nonlinear effects, or failed to survey an adequate sample of individuals with extreme scores. Future researchers should take care to obtain adequate samples of individuals with a broad range of psychotic-like symptom severity, and to explore the possibility that nonlinear relationships may exist between such symptoms and outcome (e.g., outcome may be attenuated only for those patients with extremely high levels of psychotic-like symptoms).
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