Definition and Diagnosis
Obsessive-Compulsive Disorder (OCD) is characterized by obsessions — recurrent, intrusive, and unwanted thoughts, images, or urges that cause marked anxiety — and compulsions, repetitive behaviors or mental acts performed to reduce that anxiety or prevent a feared outcome.
Epidemiology
OCD affects approximately 1-2% of the population over a lifetime and typically has two peaks of onset: childhood/adolescence and early adulthood. It affects men and women at roughly similar overall rates, though symptom themes can differ by sex.
Risk Factors
Family history, certain streptococcal infections in children (PANDAS), and temperamental traits such as heightened harm-avoidance contribute to risk. Stressful life events can also trigger onset or worsening of symptoms.
Symptoms and Subtypes
Common obsession themes include contamination, symmetry, harm, and unwanted taboo thoughts, paired with compulsions such as washing, checking, counting, or mental rituals. Compulsions typically provide only temporary relief, reinforcing the cycle.
Diagnosis
Diagnosis under DSM-5-TR requires obsessions and/or compulsions that are time-consuming (more than an hour a day) or cause significant distress or impairment. Clinicians use structured interviews and scales such as the Y-BOCS to assess severity.
Treatment
Exposure and Response Prevention (ERP), a specialized form of CBT, is the gold-standard psychotherapy, often combined with SSRIs at higher doses than typically used for depression. In severe, treatment-resistant cases, additional options such as augmentation strategies may be considered.
Prognosis
OCD often follows a chronic course if untreated, but ERP and medication produce meaningful symptom reduction for most individuals. Maintenance of gains typically requires continued practice of ERP skills over time.
Reference
Kaplan, H. I., & Sadock, B. J. (2022). Kaplan & Sadock's Synopsis of Psychiatry (12th ed.). Wolters Kluwer.