Treatments for Obsessive-Compulsive Disorder (Edexcel A-Level Psychology): Revision Notes

Treatments for Obsessive-Compulsive Disorder

Biological treatment: drug therapy

Overview

Drug therapy represents the recommended treatment for individuals with mild to moderate OCD, typically involving a short course of cognitive behavioural therapy (CBT). For those with more severe symptoms or cases where CBT has not been effective, medication becomes the primary intervention. Various drug treatments target the considerable anxiety associated with OCD.

Mechanisms of drug action

GABA and anti-anxiety medications

Anxiety in the brain is regulated by GABA (gamma-aminobutyric acid), an amino acid that reduces physiological arousal and returns the body to a resting state after periods of heightened anxiety. Benzodiazepines, such as Valium, are anti-anxiety medications that enhance GABA's effectiveness in regulating anxiety, helping restore normal arousal levels.

Beta blockers

Beta blockers offer an alternative approach by targeting the physiological manifestations of anxiety. These medications block stress hormones released by the adrenal glands into the bloodstream. By preventing the normal physiological effects of these hormones—such as increased heart rate and respiration—beta blockers help reduce both the physical anxiety response and the obsessional thoughts that lead to compulsive behaviour.

Antidepressant medications (SSRIs)

The most commonly prescribed treatment for OCD involves antidepressant medication, particularly drugs that affect serotonin levels at the synapse. Selective serotonin reuptake inhibitors (SSRIs) work by blocking serotonin reuptake from the synapse back into the releasing neuron. This mechanism increases the amount of serotonin available for longer periods, thereby increasing activity on serotonergic pathways.

Examples of SSRIs include fluoxetine and sertraline. The dosage prescribed for OCD is higher than that used for depression.

Evaluation of drug therapy

Strengths

Drug therapy can be combined with CBT, and research demonstrates this combination increases CBT's effectiveness. The POTS study found that CBT was superior to drugs alone when effective, but adding drugs to CBT improved outcomes when CBT was perhaps less effective. However, this study focused only on children and adolescents and did not examine more severe cases.

Treatment prescription must reflect individual differences between patients, as outcomes vary. This is particularly important when considering refractory OCD (obsessive-compulsive disorder that is difficult to treat). Research indicates the type of treatment most suited to a specific person varies.

Weaknesses

Transient side effects are common with drug treatments, including nausea and headache. In rare cases, there can be increased anxiety, leading to self-harm and increased suicide risk.

In cases where SSRIs have not been effective, a tricyclic antidepressant may be prescribed to augment treatment. However, these carry more serious side effects and can negatively impact people with other problems, such as heart conditions.

Drug treatments alone cannot treat most people with OCD effectively; they are most effective when combined with other therapy forms such as CBT. Ravizza et al. (1996) found that SSRI drugs were not effective for 40 per cent of people.

Drug treatment must be sensitive to individual differences. Brody et al. (1998) found that differences in metabolism in the right compared to the left orbitofrontal cortex predicts whether the person will respond better to CBT or to drugs. Given that most diagnosticians do not have access to this information, which can only be gained by advanced scanning techniques such as positron emission tomography (PET), it suggests that treatment prescription might be a bit 'hit and miss'.

Research evidence

Psychological treatment: cognitive behavioural therapy

Overview

Cognitive behavioural therapy combines elements of the cognitive approach with conditioning from the behaviourist approach. It is the first choice treatment for OCD and a brief course is recommended by the National Institute for Health and Care Excellence (NICE) in the UK for most cases of moderate severity. The treatment is goal-oriented and short-term (about three months). It is possible to have a purely cognitive therapy based on changing thought patterns or a behaviourist one based on systematic desensitisation. In practice, however, most therapists combine the two approaches.

Cognitive therapy approach

The aim of cognitive therapy is to identify and modify patterns of thought that cause anxiety and, in doing this, change how the person responds.

In OCD, intrusive thoughts cause beliefs that activate the negative emotion of anxiety. The goal of therapy is not to remove the intrusive thoughts but to change the belief they trigger. This is achieved by asking the client to recall a recent episode that triggered intrusive thoughts and then examining the meaning of the thoughts. The therapist helps the client to challenge the meaning by exploring what makes them anxiety-provoking. This is done in a graduated way, starting with thoughts that are least anxiety-provoking and encouraging the client to test the belief that the thoughts activate until they no longer automatically generate anxiety.

Exposure and response prevention therapy (ERPT)

ERPT is a behaviourist treatment that requires the person to be highly motivated to get better as it involves facing their fears. The client is active in the treatment where they have to keep confronting the fears identified as triggering a compulsion without engaging in the compulsive behaviour. The therapy takes between 14 and 16 weeks on average and consists of regular sessions with a therapist, lasting about an hour on average, and a lot of home practice.

Procedure

The ERPT process follows a systematic approach:

1. The first stage is to develop a hierarchy of situations that provoke obsessional fears, starting with the least anxiety-producing situation and ending with the most anxiety-producing situation, directly or through imagining, and then resisting the compulsion to perform the ritual that it triggers for a set period of time.

2. For example, the client may have a fear of contamination, and their least-feared situation might be shaking hands with someone. They would be asked to shake hands and then wait for a short time initially, but longer later, before they engage with the ritual.

3. The client should record their anxiety levels and thoughts as they do this. At the end of the set time they may complete the ritual or they could choose not to perform it at all. This process should be repeated several times a week until the client can engage with the trigger without anxiety.

4. After that, the next most fearful situation would be tackled, for example, touching a clean bin, and the process is repeated.

5. The client is trained to monitor their anxiety levels in order to record how they feel accurately and to notice differences as they emerge. This therapy is estimated to be effective in reducing symptoms in the majority of clients.

Evaluation of CBT

Strengths

The therapy has been promoted as the first choice by NICE as it has been shown to be effective in reducing symptoms, and it can be applied flexibly. For example, it can be delivered as group therapy or online, with a therapist monitoring the completion of worksheets and an activity plan. It is cost-effective and time-limited, showing an improvement in more than 50 per cent of cases. Its effectiveness is increased when combined with drugs.

The therapy is ethical as it allows the person to take control of their own treatment because they identify the specific issues to work on. However, it may be uncomfortable for them as they have to face up to their fears and habituate to them. Unlike drug treatments, it does not have any side effects.

Weaknesses

In evaluation, ERPT would not be effective for clients that do not have compulsions. Masellis et al. (2003) found that a substantial proportion of clients (up to 44 per cent) only suffer from obsessions. They also found that up to 75 per cent of OCD clients also suffer with comorbid depression, which lessens the effectiveness of ERPT.

The success of the therapy relies on a good interpersonal relationship between the client and the therapist, perhaps because a high degree of motivation is required. This means that tests of its effectiveness are confounded by the therapist effect as the success of the therapy depends on more than just the nature of the therapy.

Wider issues and debates: ethics and surgical interventions

Surgical interventions for refractory OCD

For individuals with refractory OCD, the NHS has established a centre to treat cases where more mainstream methods have not been effective.

Deep brain stimulation

One technique that has been developed recently is deep brain stimulation. In this technique, a surgeon implants electrodes in the brain and connects them to a small electrical generator in the body. Deep brain stimulation does not permanently destroy neural tissue, as surgery does. Instead, it uses electricity to modulate the transmission of brain signals. There are fewer side effects and recent small-scale studies show this to be effective for about two-thirds of patients.

Neurosurgery (ablation)

Another surgical intervention to treat OCD is neurosurgery. This involves the destruction (ablation) of small amounts of brain tissue within the areas known to be implicated in the symptoms of OCD. This has been estimated to be effective in about half of the people treated but risks include seizures, personality changes, and more transient side effects associated with surgery and anaesthesia.

Ethical considerations

The ethical issues of psychosurgery are substantial. This is especially true when the surgery is irreversible. However, such interventions are only offered as a last resort and as knowledge increases about the structure and function of the brain, such surgeries can be more effective and may become more mainstream.

Ablation techniques are only used as a treatment of last resort but do bring relief to those with severe refractory symptoms. Typically, those offered the surgery will have an extended history of failed treatments so it might offer a 'ray of hope' to those who have tried everything else. As knowledge develops about the specific neuro-circuits involved, then we can expect this treatment to be refined and be offered more widely, although at present it is largely experimental.

Similarly, deep brain implants, although not irreversible and with fewer side effects, other than those associated with the surgery involved in implanting the devices, are still in the early stages of research. With improved knowledge from clinical trials, specific targets for the implant will be found and there is already an improving picture of the effectiveness of this intervention emerging from small-scale trials.