Textbook of Psychiatry
H9 Obsessive-Compulsive and Related Disorders
Behaviours that are part and parcel of normal life but become out of control, excessive and
cause dysfunction in various areas of life are called obsessive-compulsive and related
disorders. There are different disorders that fall into this category:
Obsessive compulsive disorder (OCD): if the feeling of danger, insecurity,
vulnerability and anxiety increases to the point where it becomes distressing.
Reassuring thoughts and behaviours may also increase .
Body dysmorphic disorder
Hoarding disorder
Trichotillomania (hair-pulling disorder)
Excoriation disorder (skin-picking disorder)
Substance/medication-induced obsessive-compulsive and related disorders
Obsessive-compulsive and related disorders due to another medical condition
These disorders all involve repetitive thoughts and behaviours and inability to inhibit them
sufficiently (disinihibition). They also run in the family and overlap in terms of comorbidity,
age of onset and response to treatment. The same neuronal circuits appear to be involved
(cortico-striato-thalamocortical).
Syndromes:
Obsessive-compulsive disorder:
Obsessive-compulsive disorder is characterised by obsessions (compulsive thoughts, urges
and/or images) and/or compulsions (compulsive actions, including mental acts). Patients
experience them as not-self, imposed and unwanted. They are unable to ignore them, or
only with great difficulty.
, Subtypes of OCD:
1) Fear of contamination, compulsive washing
These patients are obsessed with the possibility of contamination by dirt, asbestos,
bacteria and viruses or excretion products. To reduce or neutralise this anxiety they
perform washing and cleaning rituals and avoid contact with these things.
2) Fear of dangerous events, compulsive control
These patients believe strongly in events that could occur for which they would be
responsible. The anxiety is reduced by performing control rituals and avoiding
anxiety-provoking situations.
3) Aggressive, sexual and religious obsessions and compulsions
The phenomenon of thought-action fusion plays a major role in this category: the
individual thinks that the likelihood of something happening is greater if he thinks
about it; ‘If I think that my mother could have an accident it is more likely to actually
happen’.
4) Symmetry obsessions and compulsions, and compulsive counting, ordering and
hoarding and being obsessed with this.
Patients have compulsive thoughts that all sorts of things need to be precisely ‘right’.
5) Hoarding compulsion can also occur as a separate phenomenon without obsessions
and compulsions (hoarding disorder).
Patients have far less anxiety than those with e.g. fear of contamination.
Body dysmorphic disorder:
These patients are preoccupied with perceived defects or flaws in their physical appearance
that are not observable or appear slight to others. These can relate to any part of the body.
They mainly consult specialists other than psychiatrists. Risk of surgical intervention is high if
the body dysmorphic disorder goes unrecognised. Their sense of reality is often diminished
or absent and a large proportion of them have delusions of reference. Suicide risk is high.
Hoarding disorder:
This is a pathological hoarding compulsion combined with inability to discard possessions
which takes on such proportions that living areas are difficult or impossible to use. The
hoarded material is often objectively worthless. The collecting causes stress, housing
problems and conflicts with other members of the household, local residents or the local
authority, and can present a hazard to others.
H9 Obsessive-Compulsive and Related Disorders
Behaviours that are part and parcel of normal life but become out of control, excessive and
cause dysfunction in various areas of life are called obsessive-compulsive and related
disorders. There are different disorders that fall into this category:
Obsessive compulsive disorder (OCD): if the feeling of danger, insecurity,
vulnerability and anxiety increases to the point where it becomes distressing.
Reassuring thoughts and behaviours may also increase .
Body dysmorphic disorder
Hoarding disorder
Trichotillomania (hair-pulling disorder)
Excoriation disorder (skin-picking disorder)
Substance/medication-induced obsessive-compulsive and related disorders
Obsessive-compulsive and related disorders due to another medical condition
These disorders all involve repetitive thoughts and behaviours and inability to inhibit them
sufficiently (disinihibition). They also run in the family and overlap in terms of comorbidity,
age of onset and response to treatment. The same neuronal circuits appear to be involved
(cortico-striato-thalamocortical).
Syndromes:
Obsessive-compulsive disorder:
Obsessive-compulsive disorder is characterised by obsessions (compulsive thoughts, urges
and/or images) and/or compulsions (compulsive actions, including mental acts). Patients
experience them as not-self, imposed and unwanted. They are unable to ignore them, or
only with great difficulty.
, Subtypes of OCD:
1) Fear of contamination, compulsive washing
These patients are obsessed with the possibility of contamination by dirt, asbestos,
bacteria and viruses or excretion products. To reduce or neutralise this anxiety they
perform washing and cleaning rituals and avoid contact with these things.
2) Fear of dangerous events, compulsive control
These patients believe strongly in events that could occur for which they would be
responsible. The anxiety is reduced by performing control rituals and avoiding
anxiety-provoking situations.
3) Aggressive, sexual and religious obsessions and compulsions
The phenomenon of thought-action fusion plays a major role in this category: the
individual thinks that the likelihood of something happening is greater if he thinks
about it; ‘If I think that my mother could have an accident it is more likely to actually
happen’.
4) Symmetry obsessions and compulsions, and compulsive counting, ordering and
hoarding and being obsessed with this.
Patients have compulsive thoughts that all sorts of things need to be precisely ‘right’.
5) Hoarding compulsion can also occur as a separate phenomenon without obsessions
and compulsions (hoarding disorder).
Patients have far less anxiety than those with e.g. fear of contamination.
Body dysmorphic disorder:
These patients are preoccupied with perceived defects or flaws in their physical appearance
that are not observable or appear slight to others. These can relate to any part of the body.
They mainly consult specialists other than psychiatrists. Risk of surgical intervention is high if
the body dysmorphic disorder goes unrecognised. Their sense of reality is often diminished
or absent and a large proportion of them have delusions of reference. Suicide risk is high.
Hoarding disorder:
This is a pathological hoarding compulsion combined with inability to discard possessions
which takes on such proportions that living areas are difficult or impossible to use. The
hoarded material is often objectively worthless. The collecting causes stress, housing
problems and conflicts with other members of the household, local residents or the local
authority, and can present a hazard to others.
