Obsessive Compulsive Disorder

Question 1

Who does OCD affect?

Answer 1

-0.8-3% prevalence in adults, 0.25-2% in children / adolescents
-Onset is commonly in late adolescence and early 20s

Question 2

What causes OCD?

Answer 2

-Obsessions = unwanted intrusive thoughts, images or urges that repeatedly enter a person’s mind
-Compulsions = repetitive behaviours or mental acts that the person feels driven to perform (can be overt or covert)
-Aetiology:
–Genetic predisposition has been suggested
–Developmental factors eg abuse, neglect, isolation
–Personality characteristics
–Stressors eg pregnancy, postnatal period
–Can be a presenting sign of frontotemporal dementia, trauma

Question 3

How does OCD present?

Answer 3

ICD-10 criteria:
-Either obsessions AND/OR compulsions must be present on most days for at least 2 weeks
-Acknowledged as originating in the mind and not imposed by outside influences
-Repetitive and unpleasant
-Subject tries to resist them but at least one remains
-Thoughts cause distress and interfere with daily life
-Carrying out the compulsive act is not in itself pleasurable
-Often a sense of fear if they do not carry out the compulsion

Question 4

What are the differential diagnoses for OCD?

Answer 4

-Depression
-Social and other phobias
-Alcohol misuse
-GAD
-Body dysmorphia
-Eating disorders
-Schizophrenia
-Bipolar disorder
-Tourette’s

Question 5

How would you investigate a patient with OCD?

Answer 5

-Patients are unlikely to volunteer their symptoms so a detailed history is vital
-Complete MSE
-Risk assess

Question 6

What treatment would you consider for someone with OCD?

Answer 6

Mild:
-Can be managed with low-intensity psychological treatment eg CBT, exposure and response prevention
-SSRI if failure to engage in CBT
Moderate:
-Choice between CBT / ERP and SSRI
Severe:
-High-intensity psychological therapy + SSRI

Question 7

What is ERP?

Answer 7

-Specifically designed for OCD
-Encouraged confrontation of obsessions and resisting the urge to carry out compulsions