What is obsessive compulsive disorder (OCD) and how is it typically treated?

Obsessive-Compulsive Disorder (OCD)

Definition and Core Features

OCD is a neuropsychiatric disorder characterized by the presence of obsessions (repetitive, intrusive, unwanted thoughts, images, or urges causing marked anxiety) and/or compulsions (repetitive behaviors or mental acts performed to reduce anxiety or prevent dreaded outcomes), which are time-consuming (>1 hour daily) and cause clinically significant distress or functional impairment. 1

Key Diagnostic Components

• Obsessions are recurrent and persistent thoughts, urges, or impulses experienced as intrusive and unwanted, causing marked anxiety or distress in most individuals 1
• Compulsions are repetitive behaviors (hand washing, checking, ordering) or mental acts (praying, counting, repeating words silently) that the individual feels driven to perform in response to an obsession or according to rigid rules 1
• The behaviors or mental acts are not connected in a realistic way with what they are designed to neutralize or prevent, or are clearly excessive 1

Common Symptom Dimensions

• Contamination concerns with washing/cleaning compulsions 1
• Harm-related obsessions with checking behaviors 1
• Intrusive aggressive or sexual thoughts with mental rituals 1
• Symmetry concerns with ordering or counting compulsions 1
• Avoidance is a key feature, with individuals curtailing activities to prevent triggering obsessions 1

Insight Specifiers

• Good or fair insight: patient recognizes OCD beliefs are definitely or probably not true 1
• Poor insight: patient thinks OCD beliefs are probably true 1
• Absent insight/delusional beliefs: patient is convinced OCD beliefs are true; this must be distinguished from psychotic disorders to avoid inappropriate treatment 1

Differential Diagnosis Considerations

• Normal intrusive thoughts and rituals are common in the general population but do not meet the time-consuming (>1 hour daily) or significant distress/impairment criteria 1
• Generalized anxiety disorder and depression involve worries about real-life concerns that are less irrational and ego-dystonic than OCD, without typical compulsions 1
• Substance-related and addictive disorders have an ego-syntonic, gratifying component that is fundamentally absent in OCD 1, 2
• OCD symptoms are ego-dystonic (unwanted), whereas personality disorders involve ego-syntonic traits 3

Neurobiological Basis

• OCD is mediated by cortico-striato-thalamo-cortical circuits involving sensorimotor, cognitive, and affective processes 3
• Functional imaging consistently shows hyperactivity in the orbitofrontal cortex, anterior cingulate, thalamus, and striatum 4

Evidence-Based Treatment

First-Line Pharmacotherapy

• Serotonin reuptake inhibitors (SRIs) are the backbone of pharmacological treatment, requiring 10-12 weeks at adequate doses 1, 5
• FDA-approved medications include sertraline and paroxetine for treatment of obsessions and compulsions 6, 7
• SSRIs should be initiated first due to superior safety and tolerability compared to clomipramine, with equivalent efficacy 5

First-Line Psychotherapy

• Cognitive-behavioral therapy with exposure and response prevention (ERP) is the evidence-based psychotherapy for OCD 1, 3
• ERP involves exposing patients to anxiety-provoking stimuli while preventing the compulsive response 8, 4

Treatment-Resistant Cases

• For non-responders to initial SSRI: switch to a different SSRI, combine with behavioral therapy, or consider pharmacological augmentation 5
• Antipsychotic augmentation is most commonly employed for treatment-resistant OCD 4
• Neurosurgical procedures (gamma knife radiation, deep brain stimulation) are reserved for severe, treatment-refractory disease unresponsive to multiple treatments 4

Clinical Pitfalls to Avoid

• Do not misdiagnose OCD with absent insight as a primary psychotic disorder, as this leads to inappropriate treatment 1
• Recognize that patients often hide symptoms due to shame, resulting in years of delay between symptom onset and appropriate treatment 4
• Males are more likely to have early-onset OCD (before puberty) and comorbid tics, requiring tailored evaluation and management 1