Obsessive-Compulsive Disorder (OCD)

• Anywhere between 60-90% of individuals with OCD also have a comorbid mental disorder, including mood, anxiety, somatoform disorders, substance use disorders, psychotic disorders, and bipolar disorders.
  • In children, with OCD, there is a 5 to 7% incidence for Tourette's, and up to 30% have a life-time history of tics.^[7]
  • In children, OCD and ADHD are highly comorbid.^[8]
  • Lifetime prevalence for any co-morbid anxiety disorder (e.g. - panic disorder, social anxiety disorder, generalized anxiety disorder, specific phobia) is 76%.^[9]
  • Lifetime prevalence for any co-morbid mood disorder is 63%, with major depressive disorder being the most common (41%).^[10]
  • Comorbid obsessive-compulsive personality disorder (OCPD) is also common (between 23-32%).^[11]
• Many psychiatric and neuropsychiatric disorders also exist on the OCD spectrum (figure 1).^[12]

Fig. 1

Criterion A

Presence of obsessions, compulsions, or both:

Obsessions are defined by (1) and (2):

1. Recurrent and persistent thoughts, urges, or images that are experienced, at some time during the disturbance, as intrusive and unwanted, and that in most individuals cause marked anxiety or distress
2. The individual attempts to ignore or suppress such thoughts, urges, or images, or to neutralize them with some other thought or action (i.e. - by performing a compulsion)

Compulsions are defined by (1) and (2):

1. Repetitive behaviors (e.g. - hand washing, ordering, checking) or mental acts (e.g. - praying, counting, repeating words silently) that the individual feels driven to perform in response to an obsession or according to rules that must be applied rigidly
2. The behaviors or mental acts are aimed at preventing or reducing anxiety or distress, or preventing some dreaded event or situation; however, these behaviors or mental acts are not connected in a realistic way with what they are designed to neutralize or prevent, or are clearly excessive

Criterion B

The obsessions or compulsions are time-consuming (e.g. - take more than 1 hour per day) or cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

Criterion C

The obsessive-compulsive symptoms are not attributable to the physiological effects of a substance (e.g., a drug of abuse, a medication) or another medical condition.

Criterion D

The disturbance is not better explained by the symptoms of another mental disorder:

• excessive worries, as in generalized anxiety disorder
• preoccupation with appearance, as in body dysmorphic disorder
• difficulty discarding or parting with possessions, as in hoarding disorder
• hair pulling, as in trichotillomania
• skin picking, as in excoriation disorder
• stereotypies, as in stereotypic movement disorder
• ritualized eating behaviours, as in eating disorders
• preoccupation with substances or gambling, as in substance-related and addictive disorders
• preoccupation with having an illness, as in illness anxiety disorder
• sexual urges or fantasies, as in paraphilic disorders
• impulses, as in disruptive, impulse-control, and conduct disorders
• guilty ruminations, as in major depressive disorder
• thought insertion or delusional preoccupations, as in schizophrenia spectrum and other psychotic disorders
• or repetitive patterns of behaviours, as in autism spectrum disorder

Most individuals with OCD will have both obsessions and compulsions. High sensitivity screening questions and a good OCD history includes the following:

1. Obsessions: Do you ever get intrusive or unwanted thoughts, images, or impulses that repeatedly enter your mind, despite you trying to get rid of them?
   • e.g. - worries about dirt/germs, or thoughts of bad things happening
2. Compulsions: Do you ever feel driven to do certain things over and over again?
   • e.g. - repeatedly washing hands, cleaning, checking doors or work over and over, rearranging things to get it just right, or repeating thoughts in your mind to feel better?
3. Does this waste significant time or cause problems in your life (Criterion B of DSM-5 criteria)?
   • e.g. - interfering with school, work, or seeing friends?

Obsessions

Obsessions can be external or internal:

• External obsessions: contamination, objects, smells, asymmetry, mismatched items
• Internal obsessions: ego-dystonic thoughts (violent, sexual, etc.), always ask: “are these thoughts intrusive in nature?”

Compulsions

Compulsions can be physical (behavioural) or mental (cognitive):

• Physical/behavioural compulsions: washing, checking, rearranging, reassurance seeking
• Mental/cognitive compulsions: mental rituals/review (“Did I actually do that obsession?”), replacing good thoughts with bad, counting, review

• Substance/Medication-induced obsessive compulsive symptoms (OCS)
  • Recent initiation of an atypical (second generation) antipsychotic that is temporally-linked to the symptoms.
• Anxiety disorders
  • Avoidant behaviors, recurrent thoughts, and the need for reassurance is also common in anxiety disorders. However these are usually real-life concerns, compared to the obsessions in OCD which usually do not involve real-life concerns (which may be odd/irrational). In addition, there are usually both compulsions and obsessions.
  • Specific phobia
    • Similar to OCD, individuals with specific phobia may have a fear reaction to specific objects or situations. However, rituals are not present.
  • Social anxiety disorder
    • In social anxiety disorder (social phobia), the feared objects or situations are limited to social interactions, and avoidance or reassurance seeking is focused on reducing this social fear.
• Major depressive disorder
  • Rumination can occur in both OCD and depression. However rumination in depression is usually mood-congruent and not necessarily experienced as intrusive or distressing. Again, ruminations are not linked to compulsions, which is common in OCD.
• Body Dysmorphic Disorder (BDD)
  • In body dysmorphic disorder, obsessions and compulsions are limited to concerns about physical appearance
  • In BDD, checking behaviours (e.g. - looking in the mirror), will further increase distress, whereas in OCD, checking behaviours usually decrease distress
• Trichotillomania
  • In trichotillomania, the compulsive behaviour is limited to only hair pulling and there are no obsessions
• Hoarding Disorder
  • In hoarding disorder, the main symptoms are severe difficulty or distress in discarding one's possessions, and excessive accumulation of objects. However, if an individual has obsessions that are typical of OCD (e.g. - concerns about incompleteness or harm), and these obsessions lead to compulsive hoarding behaviors (e.g. - acquiring all objects in a set to attain a sense of feeling “just right” or not discarding books because they may contain information that could prevent harm), a diagnosis of OCD should be given instead.
  • In hoarding, the individual usually holds a strong sentimental value and attachment towards the hoarded objects
• Eating disorders
  • In OCD, the obsessions and compulsions go beyond concerns about weight, body image, and food.
• Psychotic disorders
  • Some individuals with OCD will have very poor insight or even to the point delusional OCD beliefs. However, there will be obsessions and/or compulsions (thus ruling out delusional disorder) and an absence of other symptoms of schizophrenia or schizoaffective disorder such as hallucinations or thought disorder.

• Tic Disorders (Tics) and Tourette's
  • Tics are sudden, rapid, recurrent, nonrhythmic motor movement or vocalization (e.g. - blinking, throat clearing). A stereotyped movement is a repetitive, seemingly driven, nonfunctional motor behaviour (e.g. - head banging, rocking, biting). Tics and stereotyped movements are typically less complex than compulsions and they are not performed to neutralize obsessions. However, differentiating between complex tics and compulsions can sometimes be difficult. One way to distinguish is that compulsions are usually preceded by obsessions, whereas premonitory urges often precede tics. Since there is high comorbidity between the two disorders, there are cases were both diagnoses may apply.
• Obsessive-compulsive personality disorder
  • Obsessive-compulsive personality disorder (OCPD) and OCD have similar sounding names, but are two distinct entities. There are no intrusive thoughts, images, urges or repetitive behaviors in OCPD. Individuals instead have long-standing, pervasive maladaptive patterns of excessive perfectionism and rigid control. However, it is possible to have both diagnoses.

A specialized form of CBT, called Exposure and Response/Ritual Prevention Therapy (ERP) is the gold standard and first-line treatment for OCD, and favoured over medications.

• In ERP, patients are exposed to situations that trigger obsessions, and are taught strategies to prevent the compulsive response that would temporarily relieve their anxiety.
  • Patients gradually become desensitized to the feared stimulus, resulting in improved OCD symptoms.
• The “Exposure” in ERP refers to exposing the patient to the thoughts, images, objects and situations that make them anxious and/or trigger the obsessions.
• The “Response Prevention” part of ERP, involves teaching the patient to not perform those compulsive behaviors once those anxiety or obsessions have been triggered; instead, they are taught to perform an opposite action.
• To do ERP successfully, patients must have significant buy-in into the therapy, as it can be a very distressing experience.
• Long-term maintenance of improvement has been shown in both children and adults.
  • Involving family members to stop or reduce family accommodation of the compulsions is also important.^[27][28][29]
• An sample structure of ERP would include:
  • Delineating the range of obsessional triggers
  • Establishing the range of discomfort associated with each trigger
  • Establishing a hierarchy and rating the distress of each item (see example)
  • Treatment then proceeds by systematically exposing the patient to each of the triggers with prevention of rituals
  • There is a concurrent active homework schedule (e.g., 4 exposures per week, 2 hours each)

• Treatment with medications should be considered if CBT with ERP does not improve OCD symptoms sufficiently or is not feasible (i.e. - patient cannot face their symptoms directly).
  • Well-designed studies have shown that there is no difference between ERP alone versus ERP plus pharmacotherapy. Remember that treating with medications alone confer only a marginal improvement in symptoms (CBT is important!)!
• It is important to set up a patient's expectations of how much improvement they will have on medications (patients can expect a maximum of a 30-35% reduction a medication).
• Remember too that relapse is also more likely with discontinuation of SSRI therapy compared to CBT/ERP.
  • Patients must also be treated longer (at least 3 months) with doses near the maximum recommended doses (resulting in increased rates of adverse effects).^[32]
• Intravenous clomipramine has also been shown to be as effective, and if not more effective than SSRIs.^[33]
  • It is important to monitor for serotonin syndrome if the patient is on both an SSRI and clomipramine.
    • There is overall a low placebo response rate to medications (compare this to major depressive disorder, where the placebo response can be at least 35%).^[34]