OCD

Question 1

OCD

Answer 1

New class of disorders in the DSM-5
•used to be scattered 
 •OCD -- anxiety disorders
 •Body dysmorphic -- somatoform disorder
 •hoarding -- specifier for OCD
 •Trichotillomania/excoriation (skin picking) -- impulse control disorder

What is OCD
•intrusive, internal negative thoughts/tensions
•relief of thoughts/tensions via repetitive/ritualized behaviours
•often takes up 1+ hour per day
•obsessions: intrusive thoughts, images, or impulses (producing anxiety/distress)
•compulsions: repetitive behaviours in response to the distress from obsessions
•only need one, but usually see both (98%)
•themes are constant cross culturally

Types
•ego dystonic: not consistent with person’s sense of self, they don’t know why these thoughts came/want them to stop
•ego syntonic: feels right (consistent with values)
•pure obsessional: person has thought, can’t stop thinking about it, but no ritual can help
•pure compulsive: person will have intrusive thought, compulsion is so well practiced that person doesn’t notice distress

Question 2

Obsessions

Answer 2

Experienced as disturbing, distressing, inappropriate, difficult to control
•person recognizes obsession is in their mind (different from delusion), but insight varies
•common themes: contamination, harm to self/others, danger, sexuality, aggression, immorality, symmetry
•common emotions: anxiety, disgust, guilt, tension, “not right”, stuck

Question 3

Compulsions

Answer 3

Feels driven to person in response to obsession or according to rigid rules
•not realistically connected to feared outcome, or clearly excessive
•relief is often temporary
•overt (action based) vs covert (thought based)
•common themes: cleaning, checking, repeating, arranging, or counting

Question 4

Psychological factors

Answer 4

1. Two process model for compulsions
   •association between neutral stimuli and frightening thought
   •ritual reduces anxiety rapidly, reinforcing compulsions
2. If compulsions prevented, distress will subside over time
   •compulsions prevent learning that feared outcome won’t happen again, but difficult surpassing motor responses is common in OCD
3. The brain is a white noise generator of thoughts, some are disturbing
   •if overly disturbing, attempts to suppress
   •suppression of obsessions leads to 2x as many obsessions in OCD
   •often feel responsible for disturbing intrusive thoughts
   •attentional bias towards disturbing thoughts/difficulty filtering out negative, irrelevant, or distracting information

Question 5

Biological factors

Answer 5

Moderate heritability
•related to neuroticism
•childhood: greater heritability/genetic overlap with motor tics/tourettes
•different polymorphisms in OCD with tourettes vs without tourettes

Brain functions
1. Portico-Basal-ganglia-thalamo-cortical loop
•selection of possible behavioural responses
•complex, context specific linked behaviours
2. Basal ganglia (initiating/inhibiting motor responses)
3. Oribtalfrontal cortex/singulate cortex (PFC)
•emotion/reward motivated urges (sex,agr.)
4. Poor sensory motor gating
•unable to filter distracting thoughts
5. Seretonin dysregulation (possible overactivity)

Question 6

Prevalence

Answer 6

1 year: 1% / lifetime: 2-3%
•even gender ratio
•onset: late adolescence-early adulthood
*child onset is possible
•onset is gradual, chronic, and comes and goes (if life is good - less and vice versa)
•males: subtle that has earlier onset, greater severity, and higher heritability
•comorbidities: depression (50-80%) and anxiety
•not the same as perfectionism, GAD (is more logical) or OCPD (ego syntric)

Question 7

Treatment

Answer 7

1. exposure and response prevention
   •situation triggers obsessions, urge for compulsions but prevent them, allow discomfort to subside
   •work up hierarchy of triggering situations
   •requires practice/effort/support
2. Antidepressants (SSRIs) in high doses
3. Neurosurgery targeting CBGTC loop