Epidemiology^[1]

Studies vary but the figure for prevalence ranges from 1.7-4%.^[2] Population surveys produce different results from audits of clinical samples and seem to suggest a predominance of females. Current research in paediatric OCD is investigating a genetic predilection in some families.^[3]

Management of obsessive-compulsive disorder^[1][4][5] 

The GP's role

The National Institute for Health and Clinical Excellence (NICE) recommends referral to a specialist multidisciplinary team offering age-appropriate care. This is unlikely to be available in many areas, due to lack of resources; however, it is worth getting in touch with local mental health trusts to see what is currently available. The GP's role depends on expertise but it should be remembered that drug management should be part of a package which includes psychological care.

In all patients, however, the GP will need to:

• Identify cases - for patients at risk of OCD (depression, anxiety, body dysmorphic disorder (BDD), substance misuse, or eating disorder), ask the following questions:
  • Do you wash or clean a lot?
  • Do you check things a lot?
  • Is there any thought that keeps bothering you that you would like to get rid of but cannot?
  • Do your daily activities take a long time to finish?
  • Are you concerned about putting things in a special order or are you very upset by mess?
  • Do these problems trouble you?
• Assess severity, ie how much it is affecting the patient's ability to function in everyday life.
• Assess the risk of self harm or suicide and the presence of comorbidity such as depression.
• Arrange referral to appropriate secondary care provision.
• Ensure continuity of care to avoid multiple assessments, gaps in service and a smooth transition from child to adult services (many patients have lifelong symptoms).
• Promote understanding - make patients/families aware of the involuntary nature of symptoms. Consider patient information leaflets, contact numbers of self-help groups, etc.
• Consider the bigger picture - cultural, social, emotional and mental health needs.
• If the patient is a parent, consider child protection issues.

Management in adults

Patients with mild functional impairment - can be managed with low-intensity psychological treatment. This may involve:

• Individual cognitive behavioural therapy (CBT) plus exposure and response prevention (ERP).
• Individual CBT and ERP by telephone or internet.^[6][7]
• Group CBT.
• A couples-based course, which has been developed for patients in long-term relationships.^[8]

 One randomised comparative trial concluded that group CBT was an effective treatment but did not exclude the possibility that individual therapy was superior.^[9]

One study found that two prominent features of OCD - overestimations of danger and inflated beliefs of personal responsibility - benefited equally from CBT.^[10]

 Inference-based treatment (IBT) is a method of psychological treatment sometimes used as an adjunct to CBT in OCD patients with obsessional doubt.^[11]  

*ERP is a technique in which patients are repeatedly exposed to the situation causing them anxiety (eg, exposure to dirt) and are prevented from performing repetitive actions, which lessens that anxiety (eg, washing their hands). This method is only used after extensive counselling and discussion with the patient who knows fully what to expect. After an initial increase in anxiety, the level gradually decreases. This is extremely therapeutic, as the patient feels that they have confronted their worst fears without anything terrible happening. One study found that, providing there was adherence to a standardised treatment manual, the experience (or inexperience) of the therapist did not affect the outcome 

• Adults with mild symptoms should be offered a selective serotonin reuptake inhibitor (SSRI) if they cannot engage in low-intensity psychological treatment, if such treatment has failed, or if they opt not to have more intensive psychological treatment.
• Adults with moderate symptoms or where low-intensity psychological treatment has failed should be offered high-intensity CBT and ERP (more than 10 hours per patient) or an SSRI.
• Adults with severe symptoms should be offered high-intensity psychological therapy plus an SSRI.

Management in children^[12][13]

• Mild dysfunction - offer guided self-help. If this fails, as for 'moderate-to-severe', below.
• Moderate-to-severe - offer CBT/ERP as for adults but involve family/carers: individual or group, depending on the preference of the patient.
• If psychological treatment fails, factors which might require other interventions may be involved - eg, co-existence of comorbid conditions, learning disorders, persisting psychosocial risk factors such as family discord, presence of parental mental health problems.  In children over the age of 8, adding an SSRI might be appropriate, following a multidisciplinary review (but see below concerning safety issues).

Using selective serotonin reuptake inhibitors^[1][14]

See separate article Selective Serotonin Reuptake Inhibitors and below:

• SSRIs in adults:
  Evidence for use of SSRIs in OCD is stronger than for body dysmoprhic disorder (BDD). Caution is advised in view of increased risk of suicidal thoughts and self harm in people with depression. There is no current evidence linking the use of SSRIs for OCD per se  with increased risk of suicide.^[2]
  
  When prescribing, discuss the following and provide written supporting material:
  
  
  • Craving and tolerance do not occur.
  • There is a risk of discontinuation/withdrawal symptoms on stopping the drug, missing doses, or reducing the dose.
  • There is a range of potential side-effects (see individual drugs), including worsening anxiety, suicidal thoughts and self harm, which need to be carefully monitored, especially in the first few weeks of treatment.
  • There is commonly a delay in onset of up to 12 weeks, although depressive symptoms improve more quickly.
  • In high-risk patients, prescribe limited quantities, keep in contact especially during the first few weeks and actively monitor for akathisia (restlessness and the urge to move), suicidal ideation, increased anxiety, and agitation.
  • Monitor all patients around the time of dosage changes.
  • NICE recommends fluoxetine, fluvoxamine, paroxetine, sertraline or citalopram. There are no significant differences in efficacy.
  • If there is no response to a standard dose, check compliance, check interaction with drugs and alcohol, then consider titrating to a maximum dose according to the Product Characteristics.
  • Continue for at least twelve months, and withdraw gradually.
• SSRIs in children and young people (8-18 years):
  • Caution is advised, as there is a risk of self harm or suicide in patients with depression. Only prescribed by specialists, in conjunction with psychological therapy following assessment by a child and adolescent psychiatrist who should also be involved in dosage changes and discontinuation.
  • Sertraline and fluoxetine are the only SSRIs licensed for this use, unless significant co-existing depression is evident, in which case fluoxetine should be used.
  • Discuss adverse effects, dosage, monitoring, etc with the patient/family/carers, as per adults (see above).

Treatment failures (applicable to adults, children and young people)^[1][15][16]

The following are in conjunction with specialist assessment and multidisciplinary review:

• Try another SSRI.
• One study found that intensive behavioural therapy was effective even in cases resistant to other psychological therapies.^[17]
• Change to clonidine; however, there is a greater tendency to produce adverse effects. Do baseline ECG and check BP; start with a small dose, titrate according to response, and monitor regularly.
• Antipsychotics - are sometimes used to augment the effect of an SSRI.
• Inpatient treatment - for 'last resort' treatment failures, although one study found that many refractory cases responded to community-based specialist support.^[18]
• Residential/supportive care - for patients with chronic severe dysfunction.
• Neurosurgery - this may be considered for severely ill patients who do not respond to CBT and medication. Risks, benefits, long-term postoperative management and patient selection should all be carefully considered before embarking on treatment. Patient selection can be improved by the use of neuroimaging.^[19]    Steriotactic ablation and deep brain stimulation are currently being explored and have shown promise.^[20]