• Clinical science

Obsessive-compulsive disorder

Abstract

Obsessive-compulsive disorder (OCD) is characterized by persistent and recurring thoughts, urges, or images (obsessions) that lead to repetitive behaviors or mental acts (compulsions). Since obsessions are experienced as intrusive and involuntary as well as undesirable and unpleasurable, they generally cause anxiety or distress. While compulsive actions are generally not experienced as pleasurable, their performance may provide relief from the distress and anxiety caused by an obsession. At the same time, however, compulsions are, like the obsessions that trigger them, uncontrollable as well as time-consuming and therefore cause distress and impairment of function. Comorbidity with anxiety, mood, and tic disorders is common. Therapy typically involves cognitive behavioral therapy (CBT) and selective serotonin reuptake inhibitors (SSRIs).

Epidemiology

  • Sex: (females slightly more affected in adulthood, males slightly more affected in childhood)
  • Age of onset: average is 20 years of age; onset before the age of 14 in 25% of cases; onset after 35 is rare, as is acute onset (secondary to group A streptococcal infections)
  • Lifetime prevalence: approx. 2%

References:[1][2]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

The etiology of OCD is multifactorial. Factors that have been associated with OCD development include:

  • Genetic: familial transmission (high concordance rate of 0.57 in monozygotic twins)
  • Neurobiological: abnormalities in the orbitofrontal cortex, anterior cingulate cortex, and striatum
  • Serotonin level imbalance may play a role.
  • Infection: pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS)
  • Psychological trauma

References:[1]

Clinical features

Symptoms

  • Obsessions: recurring and intrusive thoughts
  • Compulsions: repetitive actions to provide relief from anxiety caused by obsessions
  • Can be egosyntonic or egodystonic

Comorbidities

References:[1][3]

Diagnostics

  • Diagnostic criteria (according to the DSM-5)
    • Obsessions and/or compulsions
      • Obsessions (e.g., thoughts about contamination, harm, or symmetry) defined by both:
        • Recurrent/persistent, intrusive thoughts, or urges that cause anxiety or distress
        • Attempts to suppress these thoughts or urges
      • Compulsions (e.g., repeatedly washing hands, opening and closing a door multiple times, or rearranging objects on a desk) defined by both:
        • Repetitive behaviors or mental actions (e.g., counting, repeating words) that the individual feels compelled to perform, in order to relieve anxiety brought upon by the obsessions.
        • These behaviors or mental actions may be performed in an attempt to prevent some perceived dreaded event, though they tend to be excessive and not connected in any realistic way to the event.
    • Time-consuming (E.g., ≥ 1 hour/day), or result in significant distress/impairment (school, work)
    • Not due to substance-use disorders or another medical condition
    • Not due to another mental disorder (e.g., anxiety disorders, eating disorders)

References:[1]

Differential diagnoses

Type of disorder Characteristics
Obsessive compulsive disorder Intrusive thoughts, images, and urges that trigger repetitive, compulsive behavior
Obsessive-compulsive personality disorder Excessive perfectionism and rigid control regarding real-life concerns
Generalized anxiety disorder Recurrent thoughts revolve around real-life concerns, e.g., work, as opposed to the obsessions in OCD, which tend to be of an irrational nature.
Hoarding disorder Difficulty discarding belongings
Tic disorder Tics are not responses to obsessions and/or compulsions
Body dysmorphic disorder Obsessions and compulsions revolve around physical appearance.
Trichotillomania Compulsive behavior is limited to hair pulling in the absence of obsessions.
  • Hoarding disorder
    • Epidemiology:
    • Diagnostic criteria (according to the DSM-5)
      • Persistent urge to keep items; distress associated with getting rid of items
      • Difficulty discarding belongings
      • Accumulation of belongings → intended use of belongings is compromised and living areas are cluttered
      • Clinically relevant impairment in functioning and/or clinically relevant distress
      • Not explained by other medical conditions (e.g., brain injuries) or mental illness (e.g.; OCD)
    • Treatment: cognitive behavioral therapy, if CBT fails: trial of SSRI (off-label use)
  • Body dysmorphic disorder
    • Epidemiology
    • Diagnostic criteria (according to the DSM-5)
      • Persistent preoccupation with a perceived flaw in one's physical appearance
      • Flaws are mild or not observable by others.
      • Repetitive behaviors (e.g., skin scratching) or thoughts (e.g., comparing oneself to others)
      • Clinically relevant impairments in functioning and/or clinically relevant distress
      • In order to diagnose BDD, an eating disorder that might also explain the symptoms should be ruled out.
    • Treatment: cognitive behavioral therapy, SSRIs
  • Trichotillomania (hair-pulling disorder)

References:[1][4][5][6][7][8]

The differential diagnoses listed here are not exhaustive.

Treatment

A combination of pharmacotherapy and psychotherapy has been proven effective in the treatment of OCD.

References:[9][10]