Obsessive Compulsive Disorder (OCD)

Professor David Mataix-Cols
Professor David Mataix-Cols

Professor Mataix-Cols is a clinical psychologist specialised in the study and care of patients with obsessive-compulsive and related disorders. He completed his PhD in 1999 (University of Barcelona). In 2000 he was awarded a Marie Curie Fellowship to conduct post-doctoral research at Imperial College London. From 2002, he was appointed lecturer at King’s College London, where he eventually became a full professor in 2012. In parallel, he developed his clinical activity at the Maudsley Hospital. He is now professor of child and adolescent psychiatric science at the Karolinska Institutet, Stockholm, where he runs a program of research aimed at understanding the causes of obsessive-compulsive and related disorders across the lifespan and the development of cost-effective treatments for these conditions.

From 2006-2013, he was advisor to the DSM-5 Obsessive-Compulsive and Related Disorders Workgroup. He is author of over 200 peer-reviewed publications and recipient of multiple grants and awards from the UK, US, EU, Sweden and Spain. His H-Index is 54 (ISI Web of Science) and has appeared in the Clarivate most cited researcher list for 4 years in a row (2015-2018). He is currently associate editor of the Journal of Obsessive Compulsive and Related Disorders.

Dr Amita Jassi
Dr Amita Jassi

Dr Amita Jassi is a Consultant Clinical Psychologist at the National and Specialist OCD, BDD and Related Disorder Service for Children and Young People (South London and Maudsley NHS Trust). She has worked with this client group since 2006. Amita is the lead for the BDD branch of the service as well as the research lead for the clinic. In her clinical role, she develops and delivers individually-tailored treatment packages, including intensive, home-based and inpatient treatment, as well as offering consultation and joint work with clinicians around the country.

Amita has taught and trained nationally and internationally on child and adolescent OCD and BDD. She is the author of several books including ‘Can I tell you about OCD?’, ‘OCD in Autism: a clinician’s guide to adapting CBT’ and upcoming book ‘Appearance Anxiety: a guide to understanding body dysmorphic disorder for young people, families and professionals’. She has published several papers in peer-reviewed journals on OCD and BDD and engages in media work to increase awareness and understanding of these conditions.

Dr Gazal Jones
Dr Gazal Jones

Dr Gazal Jones is a Clinical Psychologist at the National and Specialist OCD, BDD and Related Disorder Service for Children and Young People (South London and Mauds­ley NHS Trust). Gazal provides specialist assessment and evidence-based treatment to children and young people with OCD across the country. Alongside her clinical work, she works on a research project aimed at improving access to mental health services amongst ethnic minority youth. As part of this project she provides assessments and training on OCD in the community. She also provides OCD teaching on Clinical Psychology Doctorate courses, to other NHS professionals and school staff. Gazal recently supported the development of the freely available video ‘OCD is not me’ to raise awareness for OCD and the treatment available.

  • Overview

    Everyone has unpleasant thoughts, and everyone may think ‘did I lock the door?’ if they left the house in a rush. However, when it starts to impact upon your day to day life and obstruct other thoughts, you may be suffering from OCD’ – Charlotte Dennis, Obsessive Compulsive Diary

    People with Obsessive Compulsive Disorder (OCD) experience unpleasant and intrusive thoughts, images, doubts or urges (called obsessions) and repetitive behaviours (called compulsions). Compulsions are usually carried out as a way of reducing the distress caused by obsessions. OCD takes many different forms and causes distress and interference to day-to-day life.

    OCD usually starts in early adolescence but is often not diagnosed until adulthood. We don’t know what causes OCD, but several factors are thought to play a part, such as biological, psychological, and environmental factors. Although we don’t know what causes OCD, we do know that OCD is a very treatable condition. Cognitive Behavioural Therapy (CBT) with Exposure and Response Prevention (ERP) is the recommended first-line treatment for OCD in young people, and has been shown to be highly effective (NICE, 2005). Up to 80% of young people have a significant improvement in symptoms after CBT with ERP (Franklin et al., 2003; Mataix-Cols et al., 2014; Turner et al., 2014; Torp et al., 2014). For treatment to be as successful as possible it is important that parents are involved and help is sought as soon as possible. Where therapy alone is not beneficial, a combination of CBT with ERP and Selective Serotonin Re-uptake Inhibitors (SSRI) medication is the recommended option (NICE, 2005).

  • Introduction

    What is OCD?

    Obsessive Compulsive Disorder (OCD) is a common condition, characterised by obsessions and/or compulsions. Obsessions are intrusive thoughts, pictures, doubts or urges experienced as repetitive and distressing. Some common obsessions include fear about dirt or contamination, religious obsessions, unwanted aggressive or sexual thoughts and discomfort if things are not symmetrical or even (Mataix-Cols et al., 2008). Compulsions are repetitive (ritualistic) behaviours performed to reduce the anxiety or discomfort caused by obsessions. Common compulsions may include checking, ordering, cleaning, hoarding, counting and re-doing things (Mataix-Cols et al., 2008). OCD can take on many different forms and someone with OCD may therefore experience a range of different obsessions and compulsions. Some young people may recognise that obsessions and compulsions are unreasonable or excessive, whilst others may struggle to recognise this. Younger children may also struggle to describe obsessions and may express a general fear of something bad happening or things not being right (Chung & Heyman, 2008). The obsessions and compulsions associated with OCD cause distress and can interfere significantly with everyday life. For example, many children with OCD may struggle to keep up with school work.

    Prevelance

    OCD arises in early adolescence but often goes undiagnosed until adulthood (Chowdury et al., 2004; Stengler et al., 2013). As many as 1-3% of children and young people aged 5 to 15 years old will suffer from OCD (Heyman et al., 2003). Research studies show that OCD is equally common in males and females (Heyman et al., 2003) and across cultures and ethnicities (Fontenelle et al., 2006; American Psychiatric Association, 2013).

    Presentations

    Some obsessional thoughts, such as concerns with contamination or harm coming to oneself, may be more easily identified as OCD by clinicians whereas aggressive, sexual, religious and transformation obsessions (a fear of transforming into another object/person) may be more challenging to diagnose (Fernandez de la Cruz et al., 2013; Volz & Heyman, 2007). Similarly, some compulsions are easier to identify than others, as some are observable while others are not. For instance, it may be easier to observe a hand washing ritual but more challenging to identify mental rituals such as someone counting in their mind.

    Some forms of OCD, involving violent, aggressive and sexual obsessions can also be misinterpreted as risky by professionals who are not familiar with the range of presentations of OCD (Chung & Heyman, 2008; Veale et al., 2009; Fernandez de la Cruz et al., 2013). As with other forms of OCD, an assessment to determine whether these concerns are linked to distressing intrusive thoughts and compulsions can help clarify if these difficulties are due to OCD. Intrusive thoughts of a violent, aggressive or sexual nature does not mean there is a risk to others, because the individual is no more likely to act on these thoughts than someone with a ‘height phobia is to jump off a tall building’ (Veale et al., 2009, pp. 333). In other words, violent, aggressive and sexual obsessions represent intense fears, and sufferers go to great lengths (through performing compulsions) to stop them from coming true. As with other OCD presentations, the compulsions however, reinforce the obsessions because the individual is behaving as if they were true and this maintains distress.

    Avoidance and reassurance seeking are common in OCD (Chansky, 2000). Young people with OCD may avoid objects or situations that trigger obsessions or compulsions and seek reassurance repetitively after they have had a distressing intrusive thought. Those around the young person may not notice that avoidance and reassurance seeking are a part of OCD, but these behaviours serve to reinforce intrusive thoughts and increase levels of distress.

    Impact on the individual and others

    OCD can have a significant impact on both the individual experiencing it and others around them. Young people may spend a significant amount of time performing compulsions and as a result feel extremely tired. Young people may also struggle to speak to others about OCD because of shame, fears that they may be going mad or that speaking about the obsessions will make the obsession happen. This can lead young people to feel socially isolated and experience low self-esteem.

    It is very common for parents and siblings to get drawn into helping with compulsive behaviours and avoidance (often referred to as “family accommodation” of OCD). Between 60 to 90% of families report they participate in their child’s compulsions or rituals and facilitate avoidance (Peris et al., 2008). This may include cleaning objects for them or avoiding saying certain word that trigger obsessions and compulsions. Research shows that family accommodation interferes with treatment and is associated with poorer treatment outcome (Merlo et al., 2009). This is because the things that family members do for OCD have a similar effect as the young person’s compulsions – they provide temporary relief from anxiety but in the long-run they fuel the obsessional fears. It is therefore important that families are actively involved in treatment for OCD.

    OCD also impacts on school and academic functioning in approximately 50% of young people with OCD (Piacentini et al., 2003). Young people may find it difficult to get to school on time or might be late handing in work, ask questions excessively and write and re-write their work in classes. Young people may be punished for such behaviours, but it is important to remember the young person may not have control over the compulsions. Young people with OCD are also easier target for bullying because of compulsive behaviours or low self-esteem and may need additional support at school.

    OCD and other conditions

    Childhood OCD often co-occurs with other emotional problems, with up to 80% of individuals meeting criteria for at least one additional diagnosis (Pediatric OCD Study Team, 2004; Storch et al, 2008; Højgaard et al., 2018). Common additional conditions include tic disorder, depression, Autism Spectrum Disorder, learning disorders and other obsessive-compulsive spectrum disorders, such as body dysmorphic disorder and trichotillomania.

  • What we already know

    Causes
    We don’t know the cause of OCD but both individual (genetic, biological, personality) and environmental factors play a part. Individual factors include a family history of OCD or other mental disorders, birth complications such as low birth weight, breech presentation, C-section and personality factors such as feeling overly responsible for situations, high levels of self-doubt and perfectionism.

    Diagnosis and assessment
    OCD is best diagnosed by a trained mental health professional interviewing the child or young person and their parents. Young people may hide symptoms due to shame or fear and may benefit from some time on their own. Young people may also underestimate the impact OCD has on their lives and an interview with a parent can allow for another perspective.
    To receive a diagnosis of OCD according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; APA, 2013) and the International Classification of Mental and Behavioural Disorders (ICD-11; WHO, 2018), children or young people need to (1) experience obsessions and/or compulsions, (2) experience marked anxiety from obsessions and perform compulsions to reduce the anxiety, (3) spend a significant amount of time each day distressed by obsessions and/or performing compulsions and, (4) for symptoms to have a significant impact on school, friendships and home life.

    The Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS; Scahill et al. 1997) is a gold-standard clinician administered interview and can help assess for the presence of specific symptoms and symptom severity. The CY-BOCS is commonly used in research and specialist services for childhood OCD. The scale should be administered before treatment, after treatment and at follow-up, as a way to monitor improvement in symptoms.

    Treatment
    To get help, the first step is for young people and parents to discuss their concerns with their GP. The GP can then refer onto Child and Adolescent Mental Health Services (CAMHS), where trained professionals can diagnose and treat OCD. If children and young people have had treatment by their local CAMHS service and symptoms are not improving or the local service is unable to offer treatment for OCD, families can request a referral to the national and specialist OCD service for children and young people at the Maudsley Hospital, London.

    Research shows that Cognitive Behavioural Therapy (CBT) with Exposure and Response Prevention (ERP) is the most effective treatment for OCD (NICE, 2005; APA, 2007). Exposure involves facing the fear and Response Prevention involves resisting the urge to perform a compulsion. CBT with ERP involves the young person working collaboratively with a therapist in learning more about anxiety, completing an ERP hierarchy and completing ERP tasks both in session and for homework. In session, the therapist helps the young person face triggers of OCD and resist compulsions using a graded approach which involves starting with the easiest compulsion to resist and working up to the hardest (March & Mulle, 1998). Between 60 to 80% of young people have significant improvement in symptoms with effective ERP treatment (Franklin et al., 2003; Mataix-Cols et al., 2014; Turner et al., 2014; Torp et al., 2014). For treatment to be most beneficial, families and carers need to be involved and therapy should be age-appropriate (NICE, 2005).

    In addition to CBT with ERP, there is also good evidence that medication can be a helpful part of effective treatment for OCD (NICE, 2005; Pediatric OCD Study Team, 2004; Skarphedinsson et al., 2014). Most typically, medication would only be offered if psychological therapy on its own had not been successful. The medications used most commonly are Selective Serotonin Re-uptake Inhibitors (SSRIs) such as Sertraline, Fluoxetine, Fluvoxamine, Citalopram and Escitalopram. These medications work by changing the level of serotonin in key areas of the brain such as the prefrontal cortex and basal ganglia. These medications need to be prescribed by a specialist such as a psychiatrist or prescribing nurse and introduced carefully and slowly and built-up to a therapeutic dose over several weeks. It is important to note that the positive effects of SSRI medications for OCD are typically slow to emerge.

    On occasion, additional or alternative medications can be helpful in treating OCD. The medications used can depend on other difficulties that may be present, such as the presence of Attention Deficit Hyperactivity Disorder or mood problems. These medications should again be offered and monitored carefully by a specialist.

  • Areas of uncertainty

    Pure O
    Some people with OCD may describe that they only experience obsessional thoughts without any accompanying compulsions (also referred to as Pure O). However, many researchers think that obsessions are always accompanied by compulsions. It is possible that in these cases there are mental rituals, such as neutralising an intrusive thought by thinking a positive thought that are difficult to identify and/or for the young person to verbalise. CBT with ERP can still be beneficial for cases where obsessions are described without clear accompanying compulsions (Salkovskis & Westbrook, 1989).

    PANDAS
    A proportion of childhood OCD cases may be identified as having Paediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcus (PANDAS; Swedo et al., 1998). PANDAS is associated with sudden onset before puberty and episodic OCD and/or tics symptoms in response to an infection with group A beta-haemolytic streptococci. To meet criteria for PANDAS, children should have a history of two or more OCD and/or tic episodes and physical evidence of the infection. PANDAS is being studied by researchers, but we don’t yet know the exact number of childhood OCD cases that have PANDAS (Arnold & Richter, 2001). It is thought to be quite rare. With regards to treatment, the strep infection in PANDAS is best treated with antibiotics whilst the OCD symptoms are best treated using CBT with ERP (Storch, 2006).

    Hoarding as separate to OCD
    Hoarding symptoms were previously thought to be a form of OCD, but research has shown that the majority of young persons with these symptoms do not have the intrusive, repetitive and distressing obsessions and/or compulsions that characterise OCD. For this reason, a new mental disorder, called Hoarding Disorder, was recently introduced (DSM-5; APA, 2013). Hoarding disorder is diagnosed when the young person collects objects in great excess, is unable to part with them and this causes high levels of distress to them and their families. However, hoarding can also appear in the context of OCD, where there may be collecting of items associated with obsessions and compulsions (Pertusa et al., 2008). For instance, a young person may collect items and store these in their cupboard because they worry the objects are contaminated and cannot be touched. In these cases, the treatment is still the same as for other regular OCD symptoms. Hoarding disorder may require slightly different treatment approaches, which are currently being researched.

  • What’s in the pipeline?

    Internet CBT
    Internet CBT for OCD is a web-based treatment, largely completed by the young person and their family on their computer with some therapist input. This form of treatment is currently being trialed for young people with OCD across national and specialist clinics in the UK, Sweden and Australia. Research so far shows promising results, with young people rating the treatment as ‘good’ or ‘very good’ and there being significant reductions in symptoms after treatment (Lenhard et al., 2014; 2017). Internet CBT has many benefits as it requires less therapist input, can reach families in remote locations and encourages young people to take ownership of their recovery in a format that they find accessible. Internet CBT can also be beneficial for young people who struggle to speak in sessions due to embarrassment or social anxiety. However, this form of treatment may not suit everyone. For example, it may not be as helpful for young people who are unsure about whether they really want treatment. The treatment also still needs be tested for young people who have OCD and other diagnoses such as Autism Spectrum Disorder.

    Therapygenetics
    The National Institute for Health Research (NIHR) is currently conducting research to explore the links between genetics and OCD. The NIHR are collecting samples of DNA from young people with OCD and using advanced laboratory techniques to determine each individual’s genetic make-up. The hope is that through collecting DNA, we will have a better understanding of how genetic make-up is associated with treatment response in OCD. This could help clinicians to decide which treatment a young person with OCD would be most likely to benefit from.

  • Useful resources and websites

    ‘OCD is not me’

    Video on OCD describing the impact of OCD on young people and their families and what treatment involves.

    NICE guidelines 

    NICE guidelines on Obsessive-compulsive disorder and body dysmorphic disorder: treatment.

    OCD Action 
    0845 390 6232

    OCD Youth

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