Delusional disorder

Question 1

Delusional disorder - dx

Answer 1

A. Presence of one or more delusions with a duration of 1mo or longer
B. Criterion A for schizophrenia has never been met (two or more of delusions, hallucinations, disorganised speech/thinking, disorganised/catatonic behaviour, negative symptoms)
C. Apart from the impact of the delusion (s) or its ramifications, functioning is not markedly impaired and behaviour is not obviously bizarre or odd
D. If manic or major depressive episodes have occurred, these have been brief relative to the duration of the delusional periods
E. Not due to substance or another medical condition and is not better explained by another mental disorder (e.g. BDD or OCD)

Question 2

Delusional disorder - more info

Answer 2

1. Usually presents in middle or late adult life
2. Characterised by delusions
3. Auditory or visual hallucinations, if present, are not prominent
4. Less general impairment than those with schizophrenia; may have isolated areas of dysfunction related to their delusional ideas
5. Course of the disorder is variable; most pts have either persistent symptoms or a pattern of remission and relapse

Question 3

Delusional disorder - ddx

Answer 3

1. OCD and related disorders. If individual with OCD is completely conviced that his or her obsessive-compulsive disorder beliefs are true, the dx of OCD + absent insight/delusional beliefs specifier should be given rather than dx of delusional disorder
   - Similar for BDD + absent insight/delusional beliefs
2. Delirium, major neurocognitive disorder, psychotic disorder due to another medical condition (head injury, CNS infection, epilepsy)
   - Simple persecutory delusions in the context of major neurocognitive disorder = major neurocognitive disorder + behavioural disturbance
   - Substance/medication-induced psychotic disorder can be distinguished by chronological relationship of substance use/physical disorder to onset and remission of delusional beliefs
3. Schizophrenia
   - Can be distinguished due to absence of other characteristic symptoms of active phase of schizophrenia
4. Depressive and bipolar disorders and schizoaffective disorder
   - May be distinguished from delusional disorder by the temporal relationship between the mood disturbance and the delusions and by the severity of the mood symptoms
   - If delusions occur exclusively during mood episodes, the dx is depressive or bipolar disorder with psychotic features
   - Mood symptoms that meet full criteria for a mood episode can be superimposed on delusional disorder (?)
   - Delusional disorder can only be dx if the total duration of all mood episodes remains brief relative to the total duration of the delusional disturbance. If not, dx of other specified or unspecified schizophrenia spectrum/other psychotic disorder + specified/unspecified depressive disorder, or other specified/unspecified bipolar and related disorder is appropriate

Question 4

Delusional disorder - mx

Answer 4

1. CBT targeting specific delusional beliefs (can be helpful)
2. Pharmacotherapy same as for schizophrenia (3):
   a. Oral second generation antipsychotic (SGA) other than sertindole or clozapine (reserved for special cases). Start with low dose, rising to initial target dose. Increase dose if no response within next 1-2 weeks or 3-4 weeks if response inadequate
   b. Long-acting BZD (e.g. diazepam) = controlling non-acute anxiety/behavioural disturbance
   c. Tx extra-pyramidal side effects with procyclidine orally (or alternative)
3. Tx post-psychotic depression (may need to add and gradually withdraw antidepressant)

Question 5

Delusional disorder - specifiers

Answer 5

Specify whether:

1. Erotomanic (central theme of delusion is that another person is in love with the individual)
2. Grandiose (central theme of delusion = conviction of having some great (but unrecognised) talent or insight or having made some important discovery)
3. Jealous (when the central theme of the individual’s delusion is that his or her spouse/lover is unfaithful)
4. Persecutory (when the central theme of the delusion involves the invididual’s belief that he or she is being conspired agianst, cheated, spied on, followed, poisoned or drugged, maliciously maligned, harassed, or obstructed in the pursuit of long-term goals)
5. Somatic
6. Mixed type (when no one delusional theme predominates)

Specify if:
- With bizarre content (bizarre if clearly implausible, not understandable and not derived from ordinary life experiences - e.g. individual believes that stranger has removed his or her internal organs and replaced them with someone else’s organs without leaving any wounds or scars)

Specify if (the following course specifiers only to be used after 1y duration of disorder):

• First episode, currently in acute episode (acute episode = time period in which symptom criteria are fulfilled)
• First episode, currently in partial remission (partial remission = time period during which an improvement after a previous episode is maintained and which the defining criteria of the disorder are only partially fulfilled)
• First episode, currently in full remission (period of time after previous episode during which no disorder-specific symptoms are present)
• Multiple episodes, currently in acute episode
• Multiple episodes, currently in partial remission
• Multiple episodes, currently in full remission
• Continuous

Specify current severity - quantitive ax of primary symptoms of psychosis = delusions, hallucinations, disorganised speech, abnormal psychomotor behaviour and negative symptoms. Each of these symptoms may be rated for its current severity on 5-point scale. Note - dx can be made without this severity specifier

Question 6

Other notes

Answer 6

• Lifetime prevalence 0.2%. Most frequent subtype is persecutory
• In addition to the five symptom domain areas identified in the diagnostic criteria, the ax of cognition, depression and mania symptom domains is vital for making distinctions between the various schizophrenia spectrum and other psychotic disorders
• Social, marital or work problems may arise due to the delusional beliefs
• Individuals may be able to factually describe that others view their beliefs as irrational but are unable to accept this themselves (i.e. there may be factual insight but no true insight)
• Many individuals develop irritable or dysphoric mood, which can usually be understood as a reaction to their delusional beliefs
• Anger and violent behaviour may occur with persecutory, jealous and erotomanic types
• Legal difficulties can occur, esp. in jealous and erotomanic types