Compelling evidence: A beginner’s guide to obsessive- compulsive disorders

Most people’s perceptions of obsession and compulsion – if they have never experienced it personally or have encountered it among family and friends – are probably based on television and film characters who have obsessive-compulsive disorders such as Jack Nicholson playing the novelist Melvin Udall in the film As Good As It Gets, or (my own personal favourite) Tony Shalhoub’s playing Adrian Monk in the detective series Monk. Shalhoub’s portrayal of Monk as a dirt phobic, symmetrically obsessed, ex-policeman who never walks on cracks in the pavement appears to show the condition and the effect on his life in a way that everyone can understand and sympathize.

Unsurprisingly and self-evidently, obsessive–compulsive disorder (OCD) is indicated by the presence of either obsessions and/or compulsions and is a clinically heterogeneous condition. In the most recent International Classification of Diseases (10^th Edition) of the World Health Organization, a diagnosis of OCD is indicated if the obsessive and/or compulsive behaviour is present on most days for at least two weeks. To be classed as having OCD, the behaviour(s) must cause significant distress or interfere with a person’s social and/or individual functioning (typically by time wasting). Other psychiatric disorders (e.g., Tourette’s syndrome, depression, schizophrenia) may include OCD behaviours. Furthermore, the World Health Organization ranks OCD as in the top ten most handicapping illnesses as measured by lost income and decreased quality of life.

The psychiatrist Dr David Veale (The Priory Hospital North London) and one the UK’s leading experts on obsessive-compulsive disorders, provides the following two definitions and classic features for compulsions and obsessions:

• Compulsions: These are repetitive behaviours or mental acts that the person feels driven to perform. A compulsion can either be overt and observed by others (e.g. checking that a light has been switched off) or a covert mental act that cannot be observed (e.g. repeating a certain phrase repeatedly in one’s mind). Covert compulsions are usually more difficult to resist than overt ones as they are viewed as ‘portable’ (and therefore easier to perform). A compulsion is not pleasurable for the person who experiences it. This differentiates it from impulsive acts such as shopping or gambling that are associated with immediate gratification
• Obsessions: These are defined as unwanted intrusive thoughts, images or urges that repeatedly enters the person’s mind. They are distressing (i.e. the person views the thoughts and/or behaviours as repugnant or inconsistent with their personality) but originate in the person’s mind and not imposed by an outside agency. Unwanted intrusive thoughts, images or urges are almost universal in the general population and their content (e.g., the urge to push someone over, the thought that the oven has been left on, etc.) is indistinguishable from clinical obsessions. However, the difference between a normal intrusive thought and an obsessional thought is the meaning that the person attaches to the occurrence and/or content of the intrusions.

Empirical research suggests that around 2% of the general population suffer from some form of OCD with a roughly equal gender split (although some OCD disorders are more male-based – such as sex and number obsessions – and some are more female based – such as compulsive hand washing). However, prevalence rates are dictated by the screening instruments used (some of which are claimed to over-inflate the problem). However, others claim that the prevalence rates are higher because some sufferers are simply too ashamed to seek the professional help they need.

In a study led by Dr Edna Foa (University of Pennsylvania, USA) on 431 people with OCD, the most common compulsions were checking things such as gas taps (28.8%), cleaning and washing (26.5%), repeating acts (11.1%), mental compulsions such as prayers being constantly repeated (10.9%), ordering, symmetry and/or exactness (5.9%), hoarding and collecting (3.5%), and constant counting (2.1%). The same study found that the most common obsessions were contamination from dirt, germs, viruses, bodily fluids or faeces, chemicals, sticky substances, and dangerous materials (37.8%), fear of harm (23.6%), excessive concern with order or symmetry (10%), obsessions with the body or physical symptoms (7.2%), religious, sacrilegious or blasphemous thoughts (5.9%), sexual thoughts such as being a paedophile or a homosexual (5.5%), urges to hoard useless or worn-out possessions (4.8%), and thoughts of violence or aggression such as stabbing one’s own baby (4.3%).

Similar findings were found in a study led by Dr David Mataix-Cols (Institute of Psychiatry, London) and published in the American Journal of Psychiatry. Following a comprehensive literature review, they reported 12 factor-analytic studies involving more than 2,000 OCD patients were identified. These studies typically showed at least four symptom dimensions. These were (i) symmetry and ordering, (ii) hoarding, (ii) contamination and cleaning, and (iv) obsessions and checking. They concluded that the complex clinical presentation of OCD can be summarized with these few consistent, temporally stable symptom dimensions.

Scientific research has shown that OCD typically develops in early adulthood for females (i.e., in their early twenties) and in late adolescence for males, although children of both sexes can also suffer. Studies using twin and families suggest that genetic factors may also play a role in the expression of OCD although psychological factors are also important in the acquisition, development and maintenance of the disorder. There is also some evidence that OCD is associated with high intelligence. The seriousness and severity of OCD differs from one individual to the next Some people with OCD are able to hide it even from those most close to them. However, more often, OCD seriously affects relationships and can lead to irreconcilable breakdown. It can also disrupt the ability to work or study.

In relation to prognosis, both psychological interventions (e.g., cognitive-behavioural therapy) and pharmacotherapy may lead to a significant decrease in OCD symptoms for typical sufferers. However, symptoms can continue to persist even after treatment. A completely OCD symptom-free period following treatment is relatively uncommon.

Dr Mark Griffiths, Professor of Gambling Studies, International Gaming Research Unit, Nottingham Trent University, Nottingham, UK

Further reading

Eddy, K.T., Dutra, L., Bradley, R. & Westen, D. (2004). A multidimensional meta-analysis of psychotherapy and pharmacotherapy for obsessive-compulsive disorder. Clinical Psychology Review, 24, 1011-1030.

Foa, E.B., Kozak M J, Salkovskis P.M., Coles, M.E. & Amir, N. (1998). The validation of a new obsessive-compulsive disorder scale: The Obsessive-Compulsive Inventory. Psychological Assessment, 10, 206-214.

Hodgson R.J., Budd R. & Griffiths M.D. (2001). Compulsive Behaviours (Chapter 15). In H. Helmchen, F.A. Henn, H. Lauter & N. Sartorious (Eds) Contemporary Psychiatry. Vol. 3 (Specific Psychiatric Disorders). pp.240-250. London: Springer.

Mataix-Cols, D., Conceição do Rosario-Campos, M. & Leckman, J.F. (2005). A multidimensional model of Obsessive-Compulsive Disorder. American Journal of Psychiatry, 162, 228-238.

Rachman, S.J. & Hodgson, R. (1980). Obsessions and Compulsions. Englewood Cliffs, NJ: Prentice Hall.

Veale, D. (2004). Psychopathology of obsessive-compulsive disorder. Psychiatry, 3(6), 65-68.