Obsessive-compulsive disorder (OCD) is a mental health disorder characterised by the presence of persistent obsessions and compulsions. These are time consuming (e.g., take more than 1 hour per day) and/or cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
Differential diagnosis from other psychiatric disorders with recurrent thoughts and repetitive behaviours is nuanced and requires specialist guidance.
The Yale-Brown Obsessive-Compulsive Scale is useful in grading severity initially and following trials of therapy.
Patients tend to seek treatment from 3 to 4 doctors and spend on average around 9 years in treatment before a correct diagnosis is made. The average amount of time that lapses between onset of symptoms and appropriate treatment is 17 years.
Cognitive behavioural therapy in the form of exposure and response prevention, alone or in combination with a selective serotonin-reuptake inhibitor (SSRI) or clomipramine, is a first-line therapy.
While controlled trials with SSRIs have demonstrated a selective efficacy in OCD, up to 40% to 60% of patients do not have a satisfactory outcome.
OCD is a frequently debilitating and often severe mental health disorder that affects approximately 2% of the population. OCD is characterised by: (a) obsessions, defined as unwanted, disturbing, and intrusive thoughts, images, or impulses that are generally seen by the patient as excessive, irrational, and ego-alien; and (b) compulsions, defined as repetitive behaviours and mental acts that neutralise obsessions and reduce emotional distress. OCD causes significant distress and impairment in daily functioning and can have a substantial effect on the sufferer's quality of life.
History and exam
Key diagnostic factors
- presence of risk factors
- sensory phenomena
- schizotypal personality disorder
- tic disorder
- poor motor coordination
- sensory perceptual difficulties
- difficulties in sequencing of complex motor tasks
Other diagnostic factors
- male sex
- family history of OCD
- PANDAS (paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection)
- male sex (earlier onset, more chronic course, treatment resistance)
- higher frequency of compulsions (treatment resistance)
- early age of onset (treatment resistance)
- previous hospitalisations for OCD (treatment resistance)
- schizotypal personality disorder (treatment resistance)
- tic disorder (treatment resistance)
- specific or diffuse brain structural abnormalities (treatment resistance)
1st investigations to order
- no initial test
Investigations to consider
- Structured Clinical Interview for the DSM (SCID)
- Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)
- Clinical Global Impression (CGI)
mild to moderate symptoms: without comorbid personality disorders or dissociative symptoms
severe symptoms or with comorbid personality disorders or dissociative symptoms
- Obsessive-compulsive personality disorder (OCPD)
- Body dysmorphic disorder (BDD)
- Somatic symptom disorder
- Diagnostic and statistical manual of mental disorders, fifth edition, text revision (DSM-5-TR)
- Deep brain stimulation for obsessive-compulsive disorder
Obsessive-compulsive disorderMore Patient leaflets
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