cognitive therapy with obsessive-compulsive disorder: a comparative evaluation

Eehou. Res. Thu. Vol. 29, No. 3, pp. 293-300, 1991 OOOS-7967/91 $3.00 + 0.00 Printed in Great Britain. All rights reserved Copyright IC 1991 Pergamon Press plc

COGNITIVE THERAPY WITH OBSESSIVE-COMPULSIVE DISORDER: A COMPARATIVE EVALUATION

PAUL M. G. EMMELKAMP and H. BEENS

Department of Clinical Psychology, Academic Hospital, Oostersingel 59. 9713 EZ Groningen. The Netherlands

(Received 19 July 1990)

Summary-After a 4-week waiting period 21 obsessive-compulsives were randomly allocated to two treatment conditions (1) Rational Emotive Therapy (RET) and (2) exposure in uivo. RET consisted of analysing irrational thoughts; exposure in uiuo was self-controlled. After six sessions and another 4-week waiting period all patients received six sessions of exposure in vim. Both treatments resulted in significant improvement on anxiety/discomfort, Maudsley Obsessional Compulsive Inventory, and Dutch Obses- sional Compulsive Questionnaire and in a reduction of scores on the Irrational Beliefs Test. Results were maintained to a follow-up 6 months later. No significant differences were found between the two conditions.

The effects of behavior therapy, i.e. exposure in viuo and response prevention, with obsessive- compulsive patients have been well established (Emmelkamp, 1982, 1990; Rachman & Hodgson, 1980; Steketee & Cleere, 1990). Improvements have been found to be maintained up to 3.5 yr follow-up (Visser, Hoekstra & Emmelkamp, 1991). However, there are still a number of obsessive-compulsives who can not be treated or are inadequately treated by behavioural methods only (Foa. Steketee, Grayson & Doppelt, 1983; Rachman, 1983). Given the fact that most obsessive-compulsive behaviour is evoked by thoughts, in recent years some authors suggest that the role of cognitive factors such as appraisal must be considered (McFall & Wollersheim. 1979; Salkovskis, 1985, 1989).

A first attempt to investigate the clinical utility of a cognitive approach on obsessive-compulsive disorders was made by Emmelkamp, van der Helm, van Zanten, and Plochg (1980). They investigated whether a modification of cognitions could enhance the effectiveness of exposure in vivo and response prevention. The cognitive component of the treatment consisted of self-instructional training. Results indicated that self-instructional training did not enhance the effectiveness of exposure in ho. However, it is questionable whether self-instructional training is the most appropriate cognitive technique to deal with obsessive-compulsive patients who are already engaging in excessive self-talk, ruminations, and doubting. Treatment that focuses on the irrational beliefs of obsessive-compulsives might be more appropriate for these patients (McFall & Wollersheim, 1979).

Emmelkamp, Visser and Hoekstra (1988) investigated the value of rationally disputing the irrational beliefs of obsessive-compulsive patients. Rational Emotive Therapy (RET) along the lines of Ellis (1962) and McFall and Wollersheim (1979) was compared with treatment con- sisting of exposure in vivo and response prevention. Cognitive therapy was found to be as effective as exposure in vivo. However, given the characteristics of the patients who received cognitive therapy (young, well-educated, non-chronic complaints) there was a clear need to replicate this study.

The aim of the present study was to investigate whether cognitive therapy was as effective as exposure in vivo and response prevention. Further, we were interested whether a combined package (cognitive therapy followed by exposure in vim) would enhance the effects of exposure in vivo and response prevention. Previous studies have indicated that exposure in vivo may be carried out by the patient him/herself (Emmelkamp & De Lange, 1983; Emmelkamp & Kraanen, 1977; Emmelkamp, van Linden van den Heuvell, Sanderman & Riiphan, 1989) and therefore self- controlled exposure was used in the present study.

BRT 29 3--F 293

294 PAUL M. G. EMMELKAMP and H. BEENS

METHOD

Design

After an intake interview patients were randomly assigned to two conditions: (1) self-controlled exposure and (2) cognitive therapy. The design is shown in Fig. 1.

After two sessions which were devoted to assessment (assessment I) and preparation for the treatment, a 4-week waiting period followed. After another assessment session (II) six treatment sessions followed. Half of the patients received cognitive therapy, the other half exposure. After the experimental treatment, which lasted 4 weeks, another assessment (III) was held, and patients were reassessed (assessment IV) 4 weeks later. No treatment was provided during this period. After assessment (IV) the patients in the exposure condition received another six sessions of exposure; for patients in the cognitive therapy condition exposure was now added to cognitive therapy. After this second treatment phase, which lasted 4 weeks, another assessment (V) was held, followed by a 4-week no-treatment period; then patients were reassessed (Follow-up I). With two-thirds of the patients (n = IS), treatment was continued after Follow-up I. Six months after the post-test, Follow-up II was held.

Patients

Obsessive-compulsive patients who were considered for this study were referred to our department by mental health agencies and general practitioners. The program acceptance criteria were.

(1) DSM-III diagnosis of obsessive-compulsive disorder (OCD). The obsessive compulsive behaviour (ritual) had to be the main problem, to last for at least half a year and to be severe enough to warrant intensive treatment;

Week 1 ASSESSMENT I

Week 5 ASSESSMENT Kf

Week 9 ASSESSMENT m

Week 13 ASSESSMENT m

Week 17 ASSESSMENT P

/I

Week 21 Follow - up I

piiixiq

Week 44 Follow-up n

Fig. 1. Design.

Cognitive therapy with obsessive-compulsive disorder 295

(2) no previous cognitive or behavioural treatment;

(3) no psychosis; (4) not suicidal; (5) age range: 18-65.

During the course of this study 31 patients met these criteria. One patient did refuse treatment, because she did not expect that treatment would help her. Thus, treatment was started with 30 patients. During the first block of treatment seven patients dropped out, equally divided across conditions; two patients dropped out in the second block of treatment. Reasons for drop-outs were the following: marital problems felt to be more important than OCD (n = 2); not willing to do the exposure exercises or too anxious during the exercises (n = 4); RET homework assignments too difficult (n = 2); and wanting non-directive psychotherapy (n = 1). Thus, 21 patients completed the project, 10 in the cognitive condition and 11 in the exposure condition. Patient characteristics for both conditions are listed in Table 1. Both conditions were quite comparable. Differences in IQ and duration of treatment were found to be non-significant.

Therapists

Therapists were advanced clinical psychology students (three female, six male) who had followed an extensive course in behaviour therapy. In addition, all had received training in cognitive- behaviour therapy with obsessive-compulsive patients before they treated patients in this project. Twice-weekly group sessions were held, where problems that occurred during the treatments were discussed. The therapists were supervised by the senior author.

Treatment

Patients were instructed not to take any anxiety-reducing or antidepressant drug during the experimental trial. Most patients complied with these instructions. Four patients (two in the exposure condition, and two in the cognitive condition) continued to use minor tranquilizers, although occasionally. The kind of information asked for in the two sessions before treatment depended on the particular form of therapy. Treatment sessions lasted approx. 60 min.

Self-Controlled Exposure In Vivo

In the information sessions an inventory was drawn up for each patient of the stimuli that might trigger passive and active (e.g. compulsive rituals) avoidance behaviour. Next a hierarchy was constructed with the help of a fear thermometer. The degree of exposure and the degree of response prevention were structured together into one hierarchy.

At each treatment session the patient was given a number of tasks (items from the hierarchy) that he/she had to perform by him/herself at home twice a week for at least 90 min. These tasks were described clearly, written down, and discussed with the patient at length. At the beginning of each new session, the patients’ performance on the tasks of the previous session was discussed. All the items in the hierarchy had to be practiced in vivo, starting with the easiest. More difficult tasks were given only if tasks lower in the hierarchy had been performed successfully. The speed at which the patient worked through the hierarchy was determined by the patient him/herself. However, if a patient tried to avoid treatment by not choosing a new item for practice, some pressure was exerted to induce the patient to carry on practicing. Treatment consisted of two

Table I. Patient characteristics

Cognitive Exposure

(n = IO) (n = II)

SW. 2 males 3 males

8 females 8 females

Married/living together 3 5

Duration of disorder

<5 yr 6 4

>5 yr 4 7

Previous treatment 8 I

IQ 103.8 109.5

Education below middle 6 3

middle 4 8

high 0 0


components: self-controlled exposure in vivo and self-imposed response prevention. During the treatment sessions these tasks were not practiced. An example might illustrate this procedure. Patients could be instructed to touch the ground, to give people hands, to touch the toilet, or to ‘contaminate’ their houses without washing their hands or other cleaning rituals afterward. Or. in the case of checking rituals, patients could be instructed to leave the house without checking lights. gas, doors; to visit cemetries or funerals without performing their rituals; and so on. For clinical guidelines the reader is referred to Emmelkamp (1982).

Cognitive Therapy

The critical elements of this treatment involve determining the (irrational) thoughts that mediate the negative feeling (e.g. anxiety, discomfort, tension), and comforting and modifying them so that undue feelings of anxiety or discomfort are no longer experienced, and hence compulsive rituals are no longer necessary to reduce these negative feelings.

Treatment made use of Ellis’s (1962) ABC framework. A: refers to an Activating event or experience; B, to the persons’s Belief about the Activating (A) event, and C, to the emotional or behavioural Consequence, assumed to result from the Beliefs (B). In the information phase patients had to read “A rational counseling primer” (Young, 1974), which explains Ellis’s theory in simple terms, in order to enable them to analyse their irrational beliefs themselves as homework assignments.

The first stage of therapy was directed to training patients to observe and record their cognitions. By using preceded ABC homework sheets, patients learned to discriminate between the actual event and their own thoughts. The next stage of therapy involved rationally disputing the irrational cognitions. The therapist challenged the irrational beliefs in a Socratic-like fashion and the patients were instructed to do this on their own as a homework assignment. Patients had to practice analysing their problems by using the preceded ABC homework sheets. In the following therapy sessions problems encountered during the homework tasks were discussed and irrational beliefs were analysed together with the therapist, with a special emphasis on the beliefs associated with the primary and secondary appraisal process (McFall & Wollersheim, 1979). Patients were not instructed to expose themselves to fear-provoking situations. As homework assignments patients had to analyse their irrational beliefs 6 days a week for 30 min on preceded ABC sheets.

In the second phase of treatment (after assessment IV) exposure exercises were added to the cognitive treatment. A hierarchy was constructed and the patient was given tasks that he/she had to perform by himself/herself at home. In the sessions the emphasis was on analysing the irrational beliefs associated with the exposure tasks.

Treatment Integrity and Compliance

Treatment manuals were developed and used to guide the therapy. Therapists were trained extensively in the treatment to be given in this research project. Further, to assess treatment integrity, therapy sessions were audiotaped and overheard by another member of the research team. Generally, therapists adhered strictly to the therapeutic methodology.

In the exposure condition the detailed discussion in the therapy sessions revealed quite clearly whether homework assignments had been carried out or not. In the cognitive therapy condition patients had to hand over the homework sheets to the therapist. Apart from the drop-outs, the other patients, generally, complied with the homework assignments.

Assessment

Assessments were carried out on five different occasions and at Follow-up I and Follow-up II. In addition, an independent assessor, a clinical psychologist who was blind with respect to the treatment condition rated the patients at assessment II (pretest) and after the first (assessment III) and second (assessment V) treatment block.

Obsessive-Compulsive Problems

Anxiety Discomfort Scale. Patient, therapist, and assessor rated five obsessive-compulsive targets on O-8 scales for anxiety/discomfort. The data were analysed for the main obsessive-compulsive problem and other obsessive-compulsive problems separately.


saucier obsessional-compulsive Inventory (~~~r~ Rac~man & Hodgson 1980). The MOCI consists of 30 items that differentiate between obsessional patients and nonobsessional neurotic patients (range: O-30).

Dutch Obsessional-Compulsive Questionnaire (DOCQ; Kraaimaat & van Dam-Baggen, 1976). This questionnaire is primarily based on items of the Leyton Obsessional Inventory (Cooper, 1970) and consists of 32 items.

Generalization Measures

irrational Belief Test (IBT; Jones, J986). The IBT was filled in to assess the effect of treatment on the irrational beliefs of the patients. An abbreviated 30-item version, adpted for use in The Netherlands, was used (range: 30-150). The internal structure is good: Cronbach’s cf is 0.79.

Self-Rating Depression Scale (SDS; Zung, 1965; range: 23-92).

RESULTS

The data up to Follow-up I were analysed in a 2 (condition) by 6 (time) design using multivariate analyses of variance (MANOVA) (cf. O’Brien and Kaiser, 1985). Since not all patients completed Follow-up II and a number of them received additional treatment in between Follow-up I and II the results at Follow-up II were analysed separately.

Results up to Follow-up I

Results are presented in Tables 2 and 3. The overall time effect was significant on all obsessive-compulsive measures and on the IBT. On the SDS the time effect was only marginally significant (P < 0.07). Subsequent univariate analyses of variance revealed an (often highly) significant time effect during first and second treatment block on all obsessive- compulsive measures. Further, the first treatment block led to a significant reduction in depressed mood (SDS). Irrational beliefs were found to change significantly in the waiting period after the first treatment block. During the three waiting periods before, in between and after the treatment hardly any changes occurred. In the first waiting period only on the anxiety-discomfort scales a few significant changes occurred.

Table 2. Means and standard deviations (in parentheses) for cognitive therapy and exposure in rim

Assessment I Assessment II Assessment III Assessment IV Assessment V Follow-up I Follow-up II

MOCI

DOCQ

Anxiety discomfort

I

Patient

Main Therapist

Assessor

Patient

Others Therapist

Assessor

IBT

SDS

cog EXP

Cog E~P

Cog EXP

Cog EXP

Cog EXP

Cog EXP

cog EXP

Cog EXP

Cog EXP

Cog

IS.8 (6.7) 15.9 (4.6)

97.5 (20.4) 95.3 (24.2)

6.2 (2.3) SS(1.9)

6.7 (1.5) 6.7 (1.7)

17.2 (6.2) 16.3 (5.7)

97.6 (20.5) 93.6 (21.4)

12.3 (7.3) 13.7 (6.1)

80.5 (23.2) 84.8 (24.4)

9.6 (6.9) Il.7(6.1)

73.8 (15.9) 80.8 (25.9)

5.9(1.7) 5.1(1.6)

6.4(1.1) 5.8 (1.5)

107.5(12.5) 106.8 (14.9)

59.9 (12.7)

5.5 (2.4) 5.Ot2.1)

5.7 (2.5) 5.8 (1.5)

5.5 (2.7) 5.6(1.8)

5.6(1.9) 4.9(1.2)

6.0(1.2) 5.4(1.4)

5.5(1.33 5.5 (4.1)

104.2(17.8) 106.4 (I 3.9)

3.8 (3.2) 4. I (2.7)

4.5 (2.7) 4.6 (2.3)

4.1 (2.9) 4.3 (2. I)

3.8(1.9) 4.1 (1.6)

4.5(1.8) 4.0(1.4)

4.411.9) 4.7 (2.1)

97.5 (16.6) 104.6 (I I .O)

47.8 (9.4)

12.7 (7.2) 13.3 (5.8)

87.6(16.4) 86.9 (22.3)

3.7 (2.5) 4.1 (2.6)

4.8 (2.5) 4.3 (2.8)

9.6 (7.2) 12.2 (5.9)

76.6 (20.2) 83.4 (26.6)

2.6 (2.8) 3.5 (3.1)

2.6 (3.0) 2.3 (2.0)

3.5(1.9) 4.1 (1.7)

3.8 (2.1) 4.1 (1.6)

2.6 (2.5) 3.7 (2.8)

2.8 (2.9) 2.8 (2.1)

3.5 (3.0) 2.3 (I .7)

2.7 (1.8) 2.8(1.8)

2.8 (1.5) 2.7 (1.6)

3.3 (2.2) 2.7f1.9)

88.8 (18.3) 100.8(21.1)

5.9 (2.5) IO.8 (4.1)

67.3 (12.0) 79.5 (15.5)

2.9 (2.3) 2.4 (2.0)

2.8 (2.6) 2.5 (2.2)

2.6 (2.0) 2.9 (2.5)

2.7 (I .5) 2.5(1.7)

1.9(1.5) 2.6 (2.5)

1.8(1.3) 2.5 (2.0)

93.5 (19.2) 101.6(12.6)

88.9 (24.7) 103.5 117.8)

85.4 (22.4) 101.9(15.9)

56.0 (9.7) 51.4(15.3) 43.7 (10.4) 49.6 (16.4) 46.5 (14.8) EXP 59.5(ll.S) 58.8 (8.7) 52.1 (8.1) 52.3 (9.8) 49.5 (10.8) 49.9 ( I I .8) 46. I (10.0)

Cog = Cognitive therapy. Exp = Exposure in rko.

MOCI = Maudsley Obsessional-Compulsive Inventory. DOCQ = Dutch Obsessional-Compulsive Questionnaire. IBT = Irrational Beliefs Test. SDS = Self-rating Depression Scale.


Table 3. Results of the MANOVA and univariate contrasts for the time effect (F values)t

Waiting Treatment period block I I vs II II “S III

Obsessive-compulsive measures MOCI DOCQ Anxiety discomfort

1

Patient 8.11’* Main Therapist 5.351

Assessor

16.63**** I I .69**’

6.15* 6.30’ 5.56’

Others Therapist

1

Patient

Assessor Generalized measures

IBT SDS

4.71: 1X23**** 21.15’“’ 10.47***

14.86***’

Waiting Treatment Waiting period block II period

III “S IV IV “S v v “S VI

Main time effect

12.51*** 21.38””

12.14.” ll.58***

(111 “S V) 14.32””

12.46**’ 12.90***

(III “S V) 10.57”’

11.315***

6.40*” 6.02;”

6.55.” 11.19**** 12.64****

13.73**** 20.82**** 14.09****

3.40* 2.60

Condition by time

interaction

<I I.19

I .63 <I

I .73

<I I .68

<I

<I <I

tOnly significant results are reported. ‘P < 0.05; **p < 0.01; ***p < 0.005; ****p < 0.001. MOCI = Maudsley Obsessional-Compulsive Inventory. DOCQ = Dutch Obsessional-Compulsive Questionnaire. IBT = Irrational Beliefs Test. SDS = Self-rating Depression Scale.

The differential effects of both treatments are reflected in the time by condition interaction. On none of the measures the time by condition interaction was found to be significant. Further analyses using percentage of improvement in between assessment I and assessment V revealed that the cognitive-exposure condition improved significantly more on the IBT than the exposure-exposure condition [t(l9) = 1.84, P < 0.041.

Additional treatment

After Follow-up I most patients (15 out of 21) received further treatment adapted to individual needs. The techniques used are summarised in Table 3. Thus the results of individual treatments could not be assessed at the 6-month follow-up. A comparison of the results (both treatments pooled) at Follow-up I and II revealed no significant changes on any of the measures, thus indicating that the effects of treatment were maintained.

DISCUSSION

The present results demonstrate that cognitive therapy is effective with obsessive-compulsive disorder. On none of the obsessional compulsive measures was there a significant difference between cognitive therapy and exposure in uivo. There is, however, no evidence that the effects of a treatment package in which cognitive therapy and exposure in uiuo are combined is more effective than exposure in vivo alone. A significant difference between groups was found on the irrational beliefs of the patients: at the end of the second treatment block the cognitive-exposure patients were found to be more improved on the IBT than the exposure-exposure patients, thus attesting to the construct validity of the cognitive therapy. Although patients in the first cognitive block of treatment were not instructed to expose themselves to distressing situations, a number of them attempted not to give in to their compulsive urges on their own.

The first part of the present study replicates the findings of our previous study in which also cognitive therapy was found to be as effective as exposure in viuo. In the present study cognitive therapy patients were less well educated and more ‘chronic’ cases, most of them having had previous treatment for their disorder, than the patients in the Emmelkamp et al. (1988) study. This

Table 4. Additional treatments received in between Follow-UD I and Follow-up II

Additional treatment Cognitive-exposure Exposure-exposure

in = IO) (n = II)

Combined cognitive-exposure Skills/assertive training Exposure + assertive training Cognitive + assertive training Bereavement therapy No additional therapy

3 4 I I I I - I I _

4 2


study adds to our previous study in showing that a combined cognitive-exposure condition is no more effective than exposure only with obsessive-compulsives, thus corroborating results of studies with agoraphobics (Emmelkamp & Mersch, 1982; Emmelkamp, Brilman, Kuiper & Mersch, 1986). Although some have proposed (e.g. Kendall, 1983; Reed, 1985) that cognitive therapy may be inappropriate for treating obsessive-compulsives, since these patients already overemphasize their thoughts, the present results indicate that this does not necessarily have to be the case. Further studies are needed to examine for which type of obsessive-compulsive patients cognitive therapy is helpful and for which type treatment can better focus on de-emphasizing the thoughts and reducing the attention paid to it.

At present, the long term effects of exposure in vivo with obsessive-compulsives have been well established, ranging from 2 yr (Emmelkamp & Rabbie, 1981; Marks, Hodgson & Rachman, 1975; Mawson, Marks & Ramm, 1982; Kasvikis & Marks, 1988) to 3.5 yr (Visser ef al., 1991). There is a clear need to establish the long term effects of cognitive therapy with obsessive-compulsives.

Many patients in the present study received additional broad spectrum behaviour therapy after

the experimental trial, including assertive training, cognitive therapy, exposure in viva and bereavement therapy. In our experience many obsessive-compulsives have other problems in addition to the obsessive-compulsive disorder that need treatment in their own right. Further studies are needed that address the issue whether treatment based upon a functional behavioural analysis of the problems of the patient is more effective than a standardized treatment protocol, e.g. exposure in vivo or cognitive therapy.

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cognitive therapy with obsessive-compulsive disorder: a comparative evaluation

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