CRITICAL COMPARISON OF COGNITIVE THERAPY, AND EXPOSURE AND RESPONSE PREVENTION APPROACHES TO OBSESSIVE-COMPULSIVE DISORDER (OCD).
Obsessive-Compulsive Disorder (OCD) is one of the anxiety disorders characterised by persistent intrusive thoughts or images (Obsessions) with repeated voluntary actions and rituals (compulsions) to control the obsessions and accompanying distress (APA, 2000; Meyer, Souza, Heldt, Knapp, Cordioli, Shavitt, and Leukefeld, 2010).
Cognitive Therapy is focus, active, and structured form of psychological intervention, used in the treatment of emotional disorders; based on the premises that emotional disturbances are due to faulty cognition or interpretation of events (Beck, Rush, Shaw, and Emery, 1979). The historical principles of cognitive conceptualisation of psychological disturbances emerged from Stoic philosophy in general and writings of Epictetus in particular; People are disturbed not by things, but their rigid and extreme views of things (Dryden and Neenam, 2004).
Exposure and Response Prevention (ERP) is the main behavioural intervention used in the management of OCD in which the client is exposed to the feared situation and willingly prevented from doing the rituals (Kozak and Foa, 1997; Clark, 2004). The behavioural interventions have their historical underpinnings from learning theories of lawful relationships in the acquisition and maintenance of behaviour in laboratory animals (Pavlov and Gantt, 1928; and Skinner, 1938 cited by Friedman, Thase, and Wright, 2008).
The purpose of this paper is to critically compare the two main psychological interventions (cognitive therapy, with exposure and response prevention) for (OCD) with respect to theory, treatment methods, and treatment effectiveness. The main headings will be theory, treatment methods, and effectiveness. Under each of these headings will be the discussion of exposure and response prevention and cognitive therapy looking deep into existing literature. Conclusion will then be drawn base on the author’s view and current implication to practice.
There are a number of theories that have been proposed regarding pathogenesis and intervention for OCD, such as neuro-chemical theory (Zohar and Insel, 1987), and neoro-anatomical model (Rauch, Jenike, Alpert, Baer, Breiter, Savage, and Fischman, 1994). Consideration will be given to behavioural theories and cognitive theories of OCD.
Theory of Exposure and Response Prevention
The behavioural therapy of exposure and response prevention for OCD is based on the two-stage theory of fear and avoidance (Mowrer, 1939, 1953, 1960; cited by Clark, 2004; Kozak and Foa, 1997). That is; Obsessional fears and avoidance (passive and active avoidance: Compulsions).
Obsessions in ERP Theory
The first stage of the theory is the development of Obsessional fear. Obsessional fears develop through classical conditioning in which a neutral object acquires the ability to elicit discomfort (anxiety) because of its association with an aversive experience (Mowrer, 1960). It was argued that if Obsessional fears acquire their anxious properties from classical conditioning, then there should be external trauma or factors in the causation of obsessions. Steketee (1993) has observed that some obsessions can be provoked by external stimuli; about 20 to 30 percent of obsessions and intrusive thoughts do occur without external stimuli and little relationship has been observed between obsessions and environmental events. Therefore the hypothesis that obsessions are acquired through association with traumatic external stimuli is not tenable (Clark, 2004).
Rachman (1971) argued that obsessions are not similar to phobic response, because obsessions are more endogenous and could be associated with low mood. Obsessions continue because individuals fail to habituate to the intrusive thoughts and show increased sensitisation or responsiveness to the cognition (Clark, 2004). Other factors that may increase sensitivity to Obsessional fears are stress, low mood, pre-existing personality vulnerability, increase arousal, and perceived loss of control (Rachman, 1978; Rachman and Hodgeson, 1980; Reynolds and Salkovskis, 1992). Paradoxically, both avoidance and compulsive rituals contribute to lack of habituation and increase sensitivity to obsession; therefore maintaining the problem of OCD (Clark, 2004).
Obsessions are followed by physiological and subjective anxiety and distress (Boulougouris, Rabavilas, and Stefanis, 1977). For example, a client with Obsessional fear of running a pedestrian over with their car will experience a high level of anxiety and distress. The individual’s attempt to deal with the distress or anxiety created by the Obsessional fears then leads to the second part of the theory – Compulsions.
Compulsions in ERP Theory
The second stage of Mowrer’s two-stage theory involves any behaviour that is negatively reinforced by relieving the obsessive fear and reducing the anxiety. Therefore the first line of action to deal with the obsession and the anxiety it causes is avoidance of the conditioned object (Steketee, 1993). The avoidance after sometime becomes unsuccessful or impossible and therefore the person then seeks reassurance (Clark, 2004). Due to the unsuccessful nature of passive avoidance, the person with OCD then adopts active avoidance (compulsive rituals) to deal with the distress (Kozak and Foa, 1997).
Mowrer (1953) described the compulsive rituals as ‘solution learning’. This type of learning also known as avoidance learning occurs as a result of learned activity evading or preventing exposure to a fear situation (Teasdale, 1974). The active avoidance (compulsion) in OCD is strengthened through operant conditioning by temporarily helping to reduce the anxiety and the distress caused by the Obsessional fears (Emelkamp, 1982). Due to the negative reward of reducing the distress by compulsion, the individual then associates compulsions with relief from distress. Compulsion is therefore negatively reinforced. Since the anxiety relief is only short lived, the cycle of obsession, distress, and then compulsion continue leading to the maintenance of the OCD (Clark, 2004).
The down side of the behavioural theory of OCD as identified by Clark (2004) are;
- There is no enough evidence to support the proposal that obsessions are acquired through association with traumatic events.
- A small number of obsessions like musical tunes, and phrases do not lead to anxiety or distress.
- Paradoxically compulsions at time elicit distress.
- Multiple obsessions may be present in some people with OCD.
Rachman and Wilson (1980) observed that Mowrer’s theory is too simple to explain the fear acquisition; however, it did highlight the maintenance of OCD rituals. It has also influence the understanding of OCD,
Emotional Processing Theory in ERP
This is another very important theory that supports exposure and response prevention as an intervention for OCD. This theory postulates that fear is represented in memory structures serving as blueprint for fear behaviour, and therefore exposure therapy is a process by which the structures are modified (Foa and Kozak, 1986). They argued that for pathological fear to be reduced, the fear structure must be activated and information incompatible with pathological elements must be in-corporated to modify the fear structure (Foa and Kozak, 1986). Even though it supports ERP, it is cognitive theory rather than behaviour theory.
This theory does not have causal explanation of OCD, however it has outlined the process of fear related behaviour and how to deal with that using ERP as a treatment method.
Theory of Cognitive Therapy
The early cognitive theories of OCD were by Car, (1974) and McFall, (1979). Car proposed that Obsessional states were characterised by abnormally high subjective estimate of probability of occurrence of unfavourable outcome leading to high distress levels or anxiety. Compulsive rituals then develop as a means of lowering the subjective probability of occurrence of undesired outcome. Clients with OCD make a faulty threat appraisal of overestimation of probability of a threat and its negative consequences with erroneous secondary appraisal underestimating their ability to cope with the threat (McFall and Wollersheim, 1979).
The criticisms of this theory are; its attempt to bridge behavioural and psychoanalytic theories, emphasis on the unconscious cognition without elaborating on cognitive and behavioural aspects of the concept, and inability to specify the unique difference between the threat appraisal in OCD and other anxiety disorders (Salkovskis, 1985). Despite these criticisms, novel cognitive theories contain a number of key concepts bearing similarities with McFall and Wollersheim’s model (Clark, 2004).
Obsessions in Cognitive Theory
Most of the cognitive theories of OCD consider the unwanted and acceptable intrusive thoughts, impulses, and images as the origin of the pathogenesis of obsessions (Clark, 2004). Beck (1976) on the other hand described obsessions as mistaken beliefs about harm.
The inflated responsibility model is one of the most influential cognitive theories of OCD. Intrusive thoughts are normal in the general population. Salkovskis in this theory proposes that it is not the intrusive thoughts, but rather the interpretation or appraisal of the thought that determines the pathological significance (Salkovskis, 1999). The appraisal of responsibility and occurrence of neutralising activities are the critical determinants of pathogenesis of obsessions. The misinterpretation of the intrusions as signifying increase personal responsibility leads to increase discomfort and anxiety associated with hypervigilance (Salkovskis and Wahl, 2003). It has been observed that inflated sense of responsibility in the presents of specific incident might predispose someone to developing OCD (Lawrence, and Williams, 2011).
The Obsessive Compulsive Cognitions Working Group (OCCWG; 1997) has identified six cognitive domains of conceptualising OCD as follows;
- Inflated responsibility- belief that one has the power to cause or prevent harm from occurring. Shafran (2005) observed that individuals with generalised sense of inflated responsibility are likely to misinterpret intrusive thoughts as harmful.
- Overimportance of thoughts- belief that the presence of the thoughts indicates its importance.
- Overestimations of threat – exaggerated estimation of probability of harm occurring.
- Importance of controlling thoughts- erroneous belief one must control their thoughts.
- Intolerance of uncertainty- erroneous belief about the need for one to be absolutely certain in dealing with events and situations.
- Perfectionism- faulty belief in the need for things to be perfect and that the slightest mistake will result in severe consequences.
Neutralisation is described as a voluntary activity either mentally or physically intended to reduce the perceived responsibility (Salkovskis, 1999). Neutralisation is the second process in the pathogenesis of OCD according to the cognitive theory. The OCD prone individual will engage in neutralising response in order to reduce the perceived sense of responsibility for the supposed negative outcome represented by the obsession. The individual then continues to engage in the neutralisation with the belief that it leads to the reduction in responsibility, discomfort, and anxiety. The problem (obsession and compulsion) is maintained since the compulsions prevent the individual from processing any evidence that will disconfirm the erroneous belief of responsibility (Clark, 2004).
Rachman (2002) emphasised that the cognitive basis of compulsive checking are the belief that one has the responsibility to protect self and others from harm, and the misinterpretation of poor memory leading to repeated checking.
Theoretical Differences between ERP and CT for OCD
Majority of the models of ERP are derived from behavioural theories except emotional processing theory, where as all the cognitive theories are all derived from cognitive appraisal models. ERP theories are based on operant and classical conditioning while that of CT are based on misinterpretation and misappraisal of cognitive experiences. Development of CT theory has its roots from the clinic, and ERP theory on the other hand developed from the laboratory. Finally, ERP has its proposed treatment as ERP, whiles CT has cognitive restructuring as a proposed treatment.
Similarities between theories ERP and CT for OCD
The most outstanding similarity between both set of theories is that none of them has been able to explain fully the exact cause of OCD (Taylor, Abramowitz, & McKay, 2007).
Another important similarity is that both theories recognised the significant role rituals play in maintaining the OCD (Clark, and Beck, 2010).
This section will describe treatment methods employed in ERP and Cognitive therapy and then compare the two in terms of difference and similarities. National Institute for Health and Clinical Excellence (NICE) has recommended that individuals with OCD associated with moderate function should be offered CBT including ERP (NICE, 2006).
Treatment Methods in Exposure and Response Prevention
Exposure and Response Prevention (ESP) is the most widely used treatment for OCD. It is highly recommended as part of CBT treatment for OCD by NICE (NICE, 2006). ERP are the central therapeutic component of CBT (Clark, 2004; Clark and Beck, 2010). Kozak and Foa (1997) model of ERP will be described in this section. It involves exposing the client to the anxiety provoking situation (thoughts, images, items, etc) at the same time encouraging the client to actively prevent themselves from ritualising or neutralising (compulsive acts). Exposure aims to reduce obsessions while response prevention reduces compulsion (Kozak and Foa, 1997; Freeston and Ladouceur, 1998).
ERP is based on the assumption that if an individual with OCD is repeatedly exposed to stimuli that induces obsession with associated distress and anxiety, and prevented from neutralising (active avoidance; compulsion), the anxiety will diminish over time through extinction (Hinle and Franklin, 2009; Foa and Kozak, 1986).
The format of the treatment is 1 or 3 hours weekly sessions of 8 to 16 sessions (Kozak, and Foa, 1997). Hinle and Franklin, 2009 proposed 12 to 15 weekly session lasting between 60 to 90 minutes depending on the severity of the OCD. The client is provided with education on the consequences of escape and avoidance with the benefits of exposure and habituation. The client then works with the therapist to identify Obsessional fears, avoidance patterns, and compulsive rituals. Hierarchy of obsessional fears is then constructed collaboratively with the client. Exposure then begins with the medium anxiety provoking situation working towards more anxiety provoking situation without ritualising. The ritual prevention is a voluntary abstinence from rituals by the client. If the client ritualises, recontamination is done to make the ritualising pointless. The principles of exposure are that the task is graded to allow confidence and engagement; the client focuses on the exposure task; the need to prolong the exposure situation to allow habituation; and it should also be repeated to allow for extinction across practice. The exposure can be either imaginal or invivo. The client is encouraged to practice the ERP session on daily basis as homework to help with the extinction. Family members could be recruited as co-therapist with the permission of the client in ERP (Mentha, 1990); however, Emmelkamp and Vedel (2002) argued that spouse-aided therapy has not been more effective than treatment by the client alone. Finally relapse prevention is then conducted to help the client become their own therapist.
Criticism of ERP Treatment
The most common criticism of the ERP is that; there is high drop out rate of client in ERP as compared to CT (Whittal, Robichaud, et al 2008). Stanley and Turner (1995) reported that 37% of OCD clients either refused ERP, drop out, or fail to respond to treatment.
It is also reported that only a small number of treatment completers of ERP remain entirely symptom free post-treatment (Fisher, and Wells, 2005). Some subtypes of OCD such as clients with pure obsessions, mental contamination, or hoarding may not respond well to ERP (Rachman, 2003, 2006; Steketee and Frost, 2007).
Treatment Methods in Cognitive Therapy
Cognitive therapy on the other hand is based on the cognitive theories of OCD. The treatment consist of psycho-education, cognitive restructuring, behaviour experiment and relapse prevention.
Psycho-education consists of educating the client how to distinguish appraisal from obsessions, and how to monitor symptoms. Proceeding with therapy will be difficult if clients are not able to identify their faulty appraisals and neutralisation responses (Whittal and McLean, 1999; Clark, 2004). Socratic questioning style (Padesky, 1993) or down-ward arrow techniques (J, S, Beck, 1995) can be used to assist clients in discovering their faulty appraisals and pave the way for cognitive restructuring.
The aim of cognitive restructuring is to provide the client with the skills to challenge the misinterpretation of attaching importance to obsession (O’Connor and Robillard, 1999). Techniques employed here in include;
- The use of continuum Steketee, 1999; Whittal and McLean, 2002) – It helps to challenge Thought-Action Fusion moral. One end of the continuum is labelled best person ever and the other end labelled worse person ever with list of defining characteristics. The client then put themselves on the continuum.
- Calculation of probability (Steketee, 1999) – In this, comparison is made of a single threat event and cumulative probability based on series of events leading to the realisation of the catastrophe associated with the obsession.
- Estimation of responsibility using responsibility pie (Whittal and McLean, 2002; Salkovskis and Wahl, 2003) – In this exercise, a situation where the client feels responsible is identified and a list of contributing factors made. Pie chart is then created in which the client fits all the other factor with their own responsibility coming last on the pie. This is sued to challenge excessive responsibility appraisal.
- Evidence gathering technique (Steketee, 1999; Rachman, 2003) – Two- column evidence form is used to collect evidence to challenge misinterpretation of significance of threat.
Behaviour experiment is described as backbone of CBT for OCD (Clark, 2004). Some of the techniques employed in behaviour experiments are; surveys, atypical exposure, responsibility transfer, and cost benefits analysis (Clark, 2004).
Relapse prevention should be incorporated into CBT intervention for OCD (Clark, 2004). It involves educating the client on the course of OCD; ensure realistic treatment expectations, identification of triggers, awareness of re-emergence of safety behaviours and how to deal with stress (Steketee, 1999).
Differences between ERP and CT interventions
ERP uses few cognitive techniques while CT uses mostly cognitive techniques in its interventions. There is high drop out rate in ERP as compared to CT (Marks, 1997; Whittal, Robichaud, et al, 2008).
Similarities between ERP and CT interventions
They are both structured in their approach and geared towards here and now. There is no difference in the process of change in both interventions (Anholt, Kempe, de Haan et al, 2008). The next stage will look at the comparative effectiveness of both interventions.
The effectiveness of CT and ERP has been established in a number of controlled trials comparing CBT with treatment as usual. In a Cochrane meta-analysis review; eight studies with 343 participants with the diagnosis of OCD in which BT/CBT were compared with treatment as usual. Better symptom control was observed in the BT/CBT group as against treatment as usual (O’kearney, Anstey, et al, 2010).
Effectiveness of Exposure and Response Prevention
Exposure and response prevention is the first effective psychological therapy designed for OCD (Marks, 1997). ERP against anxiety management programme for OCD yielded 62% and 0% fall in symptoms respectively (Araujo, Ito, et al, 1997).
Two Randomised Controlled Trial (RCT) reported improvement of obsessive and compulsive symptoms that have been generalised to other ingrained beliefs after ERP (Lelliott, Noshirvani, et al 1988; Ito, Araujo, et al, 1995). ERP has lead to other outcomes like improvement in work and social life (Duggan, Marks, and Richards, 1992; Schwartz, 1996). Treatment gains made with ERP persist years post treatment. A review of 9 RCTs revealed that 79% of clients’ maintained about 60% improvement of ritual performance after 6 years post treatment follow-up (O’Sullivan, and Marks, 1990). In another review of 16 outcome studies involving OCD clients (n=376) treated with ERP, 76% maintained improvement after 29 months follow-up (Foa, Franklin, and Kozak, 1998).
Marks (1997) observed that ERP is not only effective for compulsions but also for obsessions. This is contrary to earlier belief that ERP was not effective for obsessions (Van Oppen, Emmelkamp, et al, 1995); however, this could be so due to the use of global irrational belief measures which are not sensitive to obsessional beliefs (Emmelkamp, van Oppen, and van Balkom, 2002). Significant improvement in obsessive beliefs was reported in two different studies (Emmelkamp, van Oppen, and van Balkom, 2002).
The effectiveness of ERP for OCD has also been demonstrated in group situation; a fall of 36% in Yale–Brown Obsessive Compulsive Scale [Y-BOCS] after 6 months follow-up (McKenzie, Blanes, and Marks, 1997).
Effectiveness of Cognitive Therapy
Cognitive intervention without explicit instructions for the client to engage in exposure and response prevention can lead to significant improvement in OCD symptoms (Clark, and Beck, 2010).
In an RCT (n=71) where client with OCD were randomly assigned to either CT or ERP. The results indicated that clients with CT demonstrated significant improvement in obsessive-compulsive symptoms, depression, anxiety and general irrational beliefs, where as ERP clients only showed improvement in some of the symptoms. There was clinical significant improvement in the CT group than in the ERP group with some indication of slight superiority of CT over ERP (van Oppen, de Haas, van Balkom, et al, 1995). In a similar study, Emmelkamp, Visser, and Hoekstra (1988) observed significant improvement on OCD symptoms with CT the ERP.
Freeston, Ladouceur, Gagnon, et al (1997) reported significant improvement in Obsessional ruminations in OCD treated with CT. A number of recent studies indicated stronger treatment effect in favour of CT (McLean et al, 2001; Franklin, Abramovitz, Bux, Zoellner, and Feeny, 2002; O’Connor, Aardema, Bouthillier, et al., 2005; Whittal et al., 2005). It has also been observed that clients who show good response to CT for OCD also experience a significant improvement in their quality of life (Diefenbach, Abramowitz, Norberg, and Tolin, 2007; Norberg, Calamari, Cohen, and Riemann, 2007).
Difference between ERP and CT in Effectiveness
As seen above, few studies reported slight differences in effectives between the two interventions. CT resulted in greater reduction in irrational beliefs than ERP (Emmelkamp, van Oppen, and Balkom, 2002). Foa, Franklin, and Kozak, 1998 argued that the reported difference between CT and ERP is meaningless since cognitive restructuring is always part of ERP.
Similarities between ERP and CT in Effectiveness
A number of research reports did observe no significant differences in effectiveness between ERP and CT. The observation is that both interventions are equally effective in the treatment of OCD (Emmelkamp and Beens, 1991; van Oppen, de Haan, et al, 1995). Even though some differences were observed, they were however not statistically significant (Clark, 2004).
The discussion has been critically comparing ERP with CT in relation to OCD. It has been looking at various theories, treatment methods, as well as effectiveness of treatment outcomes.
The most important discovery from this exercise is that there are more similarities than differences between the two interventions in terms of theory, treatment methods and effectiveness. Most authors refer to the two interventions as Cognitive and Behaviour Therapy (CBT). NICE guidelines for OCD always refer to the most effective treatment for OCD as CBT including ERP. The two interventions could therefore compliment each other for good client engagement and better outcome for both clients and services.
In my clinical experience, I am able to combine both approaches with excellent treatment outcomes. I was wondering experiences you have had in using either of the two approaches.
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