- Last edited on December 13, 2021
Delusional Disorder
Primer
Delusional disorder is a mental disorder characterized by the presence of one or more delusions that persist for at least 1 month. A diagnosis of delusional disorder is not given if the individual has ever had a symptoms of schizophrenia. Apart from the direct impact of the delusions, impairments in psychosocial functioning may be more circumscribed than those seen in other psychotic disorders such as schizophrenia, and behaviour is not obviously bizarre or odd.
Epidemiology
- The lifetime prevalence of delusional disorder has been estimated at around 0.2%, and the most frequent subtype is persecutory.[1]
- There are no major gender differences in the overall frequency of delusional disorder.
- Delusional disorder, jealous type, is probably more common in males than in females.[2]
Prognosis
Comorbidity
Risk Factors
DSM-5 Diagnostic Criteria
Criterion A
The presence of at least 1
delusion with a duration of at least 1
month.
Criterion B
Criterion A
for schizophrenia has never been met.
Criterion 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.
Criterion D
If manic or major depressive episodes have occurred, these have been brief relative to the duration of the delusional periods.
Criterion E
The disturbance is not attributable to the physiological effects of a substance or an other medical condition and is not better explained by another mental disorder, such as body dysmorphic disorder or obsessive-compulsive disorder.
Specifiers
Specifiers
Specify whether:
- Erotomanic type: This subtype applies when the central theme of the delusion is that another person is in love with the individual.
- Grandiose type: This subtype applies when the central theme of the delusion is the conviction of having some great (but unrecognized) talent or insight or having made some important discovery.
- Jealous type: This subtype applies when the central theme of the individual’s delusion is that his or her spouse or lover is unfaithful.
- Persecutory type: This subtype applies when the central theme of the delusion involves the individual’s belief that he or she is being conspired against, cheated, spied on, followed, poisoned or drugged, maliciously maligned, harassed, or obstructed in the pursuit of long-term goals.
- Somatic type: This subtype applies when the central theme of the delusion involves bodily functions or sensations.
- Mixed type: This subtype applies when no one delusional theme predominates.
- Unspecified type: This subtype applies when the dominant delusional belief cannot be clearly determined or is not described in the specific types (e.g. - referential delusions without a prominent persecutory or grandiose component).
- With bizarre content: Delusions are deemed bizarre if they are clearly implausible, not understandable, and not derived from ordinary life experiences (e.g. - an individual’s belief that a stranger has removed his or her internal organs and replaced them with some one else’s organs without leaving any wounds or scars).
Severity Specifier
Specify current severity:
- Severity is rated by a quantitative assessment of the primary symptoms of psychosis, including delusions, hallucinations, disorganized speech, abnormal psychomotor behavior, and negative symptoms. Each of these symptoms may be rated for its current severity (most severe in the last
7
days) on a 5-point scale ranging from 0 (not present) to 4 (present and severe) - Note: Diagnosis of delusional disorder can be made without using this severity specifier
Treatment
Delusional disorder is highly resistant to treatment with medication alone.[6]
Differential Diagnosis
- CNS Neoplasms[7]
Comparison of Psychotic Disorders
The term psychosis has been defined in various ways in the medical literature over time. The narrowest and current definition of psychosis is hallucinations and delusions, with the lack of reality testing or insight. A broader definition of psychosis would also include disorganized thought, emotions, and behaviour. This loose definition was more common in the past, and schizophrenia was often overdiagnosed as a result.
DSM-IV to DSM 5 Psychotic Disorder Criteria Changes
Substance Abuse and Mental Health Services Administration. Table 3.20, DSM-IV to DSM-5 Psychotic DisordersComparison of Psychotic Disorders
Type | Onset | Length | Psychotic Symptoms | Mood Symptoms | Functional Decline? |
---|---|---|---|---|---|
Brief psychotic disorder | Sudden | 1 day to 1 month | At least 1 of: • Delusions • Hallucinations • Disorganized speech • Grossly disorganized or catatonic behaviour | No | Full resolution of symptoms |
Schizophreniform disorder | Can be prodromal | 1 month to 6 months | At least 2 of: • Delusions • Hallucinations • Disorganized speech • Grossly disorganized or catatonic behaviour • Negative symptoms | No | Not required |
Schizophrenia | Can be prodromal | > 6 months | At least 2 of: • Delusions • Hallucinations • Disorganized speech • Grossly disorganized or catatonic behaviour • Negative symptoms | No | Required |
Schizoaffective disorder | Can be prodromal | Major mood episode + 2 weeks of isolated psychotic symptoms + predominantly mood symptoms over course of illness | • Delusions or hallucinations for 2 or more weeks, which must be in absence of a major mood episode (depressive or manic) during the lifetime duration of the illness | Required | Not required |
Delusional disorder | Can be prodromal | > 1 month | • One or more delusions, with no other psychotic symptoms. | No | Normal function aside from impact of delusions |
Resources
For Patients
For Providers
Articles
- Huffington Post: Woman Says She Endured 8 Days In Psych Ward Because Cops Didn't Believe BMW Was Hers (Your patients may be right!)
- Deccan Chronicle: Beware: Spy cameras are getting better (Your patients may be right!)