Download Delusional Disorder

Delusional Disorder
Dr.Arfat H. Al Dujaily
2009
Introduction
Delusional disorder is an illness characterized by the presence of nonbizarre delusions in the
absence of other mood or psychotic symptoms. Diagnostic Manual of Mental Disorders, Fourth
Edition, Text Revision (DSM-IV-TR) (APA, 2000) defines delusions as false beliefs based on
incorrect inference about external reality that persist despite the evidence to the contrary and
these beliefs are not ordinarily accepted by other members of the person's culture or subculture.
Nonbizarre refers to the fact that this type of delusion is about situations that can occur in real life
such as being followed, being loved, having an infection, and being deceived by one's spouse.
In contrast, bizarre delusions, which represent the manifestations of more severe types of
psychotic illnesses (eg, schizophrenia) "are clearly implausible, not understandable, and not
derived from ordinary life experiences" (APA, 2000).
On the other end of the spectrum, making a distinction between a delusion and an overvalued
idea is important, the latter representing an unreasonable belief that is not firmly held (APA, 2000).
Additionally, personal beliefs should be evaluated with great respect to complexity of cultural and
religious differences: some cultures have widely accepted beliefs that may be considered
delusional in other cultures.
Because of poor insight into their pathological experiences, patients with delusional disorder may
rarely seek psychiatric help and often may present to internists, surgeons, dermatologists,
policemen, and lawyers rather than psychiatrists.
History
The concept of the delusional disorder has both a very long and a very short history: while the term
of delusional disorder was only coined in 1977, the concept of paranoia has been used for
centuries. Originally, the word paranoia comes from Greek para, meaning along side, and noos or
nous, meaning mind, intelligence (Munro, 1999). The Greeks used this term to describe any
mental abnormalities similar to how we use the word insanity. In the modern world, the term
reappeared in the 17th century, and it was largely used as a generic name for mental illness.
In 1863, Karl Kahlbaum introduced the concept of paranoia as a separate mental illness: "a form of
partial insanity, which throughout the course of the disease principally affected the sphere of the
intellect" (Manschreck, 2000). He used this term to describe an illness with persistent delusions
and stable course. He noted that delusions may occur in other medical and psychiatric conditions
(Manschreck, 2000).
Later Emil Kraepelin, who observed 19 cases, continued to work on defining the concept of
paranoia, which is reflected in several editions of his famous textbook and most closely resembles
the modern definition of delusional disorder. Kraepelin viewed paranoia as uncommon, chronic
condition different from dementia praecox by the presence of fixed, nonbizarre delusions, lack of
deterioration over time, preserved thought process, and relatively slight involvement of affect and
volition (Manschreck, 2000). He described that delusions of paranoia, contrary to the delusions of
dementia praecox, are well systemized, relatively consistent, and often related to real-life events.
He identified persecutory, grandiose, jealous, erotomanic, and possibly hypochondriacal types of
that disorder. He believed that the illness derived from the deficit in the patients' judgments caused
by constitutional factors and environmental stress (Manschreck, 2000; Munro, 1999).
Later, Eugen Bleuler continued to recognize paranoia as a separate disorder and included
hallucinations in its description (Fennig, 2005; Munro, 1999).
After Kraepelin's death, Kurt Kolle (1931) reported a detailed follow-up of 66 cases seen in
Kraepelin's former clinic in Munch (Munro, 1999). He noted a pattern of deterioration and
concluded that paranoia represents a form of schizophrenia. This view continued to be popular in
the psychiatric community for several decades and was reflected in DSM-I and DSM-II. Winokur
(1977) had redescribed paranoia under the name of delusional disorder basing his findings on
Kraepelin's definition and the observation of case types (Munro, 1999). Additionally, Kendler
(1980) and Munro (1982) substantially contributed to our current understanding of nosology of this
illness (Munro, 1999; Kelly, 2005).
In 1987, delusional disorder was introduced in DSM-III-R and continued to be present in
subsequent editions.
Current Diagnosis
DSM-IV-TR (APA, 2000) defines delusional disorder with the following criteria:
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Criterion A: Nonbizarre delusions (ie, involving situations that occur in real life, such as
being followed, poisoned, infected, loved at distance, or deceived by spouse or lover, or
having a disease) of at least 1 month's duration.
Criterion B: Criterion A for schizophrenia has never been met (ie, patients do not have
simultaneous hallucinations, disorganized speech, negative symptoms such as affective
flattening, or grossly disorganized behavior). Note: Tactile and olfactory hallucinations
may be present in delusional disorder if they are related to the delusional theme.
Criterion C: Apart from the impact of the delusion(s) or its ramifications, functioning is not
markedly impaired, and behavior is not obviously odd or bizarre.
Criterion D: If mood episodes have occurred concurrently with delusions, their total
duration has been brief relative to the duration of the delusional periods.
Criterion E: The disturbance is not due to the direct physiological effects of a substance
(eg, a drug of abuse, a medication) or a general medical condition.
Subtypes are defined, including erotomanic, grandiose, jealous, persecutory, somatic,
mixed, and unspecified.
Epidemiology
The prevalence of delusional disorder in the United States is estimated in the DSM-IV-TR to be
around 0.03% (APA, 2000), which is considerably lower than the prevalence of schizophrenia (1%)
and mood disorders (5%) (Sadock, 2003).
According to the DSM-IV-TR, delusional disorder accounts for 1-2% of admissions to inpatient
mental health facilities (APA, 2000). The incidence of first admissions for delusion disorder is
considerably lower, between 0.001 and 0.003% (Kendler, 1982).
A British study reported that of 227 patients presented to mental health centers during the 3-year
study period with a first episode of psychosis, 7% were diagnosed with persistent delusional
disorder, as compared to 11% with schizophrenia and 19% with psychotic depression (Proctor,
2003). The incidence of first admission for delusional disorder in this study was 0.007%, which is
2-7 times as high as in the Kendler data.
The mean age of onset is 40 years and ranges from 18-90 years (Sadock, 2003).
The female-to-male ratio has been reported to vary between 1.18. (Kendler, 1982) and 3:1
(Yamada et al 1998 as cited in Kelly, 2005). Men are more likely than woman to develop paranoid
delusions; women are more likely than men to develop delusions of erotomania (Sadock, 2003).
Associated factors include being married, being employed, recent immigration, low socioeconomic
status, celibacy among men, and widowhood among women (Kendler, 1982; Manschreck, 2000).
Etiology
General considerations
The etiology of delusional disorder is unknown, and several difficulties exist in conducting research
in this area:
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The definition of this condition has changed over time and continues to be a work in
progress.
Patients currently diagnosed with delusional disorder may represent a heterogeneous
group of patients with delusions as the predominant symptom.
Patients often do not present for treatment, and thus they do not commonly make
themselves available for research studies.
However, strong indications exist that delusional disorder is a distinct condition, different
from schizophrenia or mood disorder. Naturalistic studies indicated that delusional
disorder has a relatively stable course
Genetics
Kendler (1981) noted significantly lower prevalence of schizophrenia in families of patients with
delusional disorder (0.6%) compared with families with schizophrenia (3.8%).
Later Kendler and his colleagues (1985) showed that a history of paranoid personality disorder
was more common in first-degree relatives of patients with delusional disorder (4.8%) compared
with medical controls (0%) and patients with schizophrenia (0.8%). In their study they found no
increased incidence of schizophrenia, schizoid-schizotypal personality disorder, and affective
illness in the first-degree relatives of delusional disorder patients.
Biochemical factors
Delusions are associated with a wide range of nonpsychiatric medical conditions, which suggest
that biological factors may play some role in the development of delusional disorder. Among
patients with neurologic disorders (primarily dementia, head injury, and seizures) conditions
involving the basal ganglia and temporal lobe are most commonly associated with delusions
(Sadock, 2003; Gorman and Cummings, 1990).
Hyperdopaminergic states have been implemented in the development of delusions. Recently,
Morimoto et al (2002) reported that 13 patients with delusional disorder were reported to have
increased levels of plasma homovanillic acid (HVA) (a dopamine metabolite) compared with
control subjects, and that the level of HVA is correlated with severity of psychotic symptoms. His
patients responded well to treatment with low-dose haloperidol (average 2.7 mg/d) and showed
decreased posttreatment plasma level of HVA, which correlated with the improvement of their
symptoms.
The same authors reported an increased prevalence of a polymorphism at the D2 receptor gene at
amino acid 311 (cysteine-for-serine substitution) among individuals with delusional disorder in their
sample who have persecutory delusions; they also reported that individuals in their sample with
more TCAT repeats within the first intron of the tyrosine hydroxylase gene have higher levels of
HVA (Morimoto, 2002), although it is unclear if they corrected
for multiple statistical comparisons.
Psychological factors
Cognitive and experimental psychology suggest that persons with delusions selectively attend to
available information, make conclusions on the basis on insufficient information, attribute negative
events to external personal causes, and have difficulty in envisaging other's intentions and
motivations (Fennig, 2005).
Conway et al (2002) reported that patients with delusional disorder required less data to make
probability decisions compared with normal controls. Despite using less data, they were as certain
as controls regarding the accuracy of their decisions.
Psychodynamic theories suggest that paranoia is a protective response to stress or conflict that
represents a threat to self-esteem or to the self (eg, unacceptable homosexual impulses, fear of
the unknown, immigration) (Fennig, 2005).
Clinical Features
General approach
Theo Manschreck (1996) outlined 3 steps in the initial evaluation of patients presented with
delusions.
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The first step in the clinical evaluation is establishing whether pathology is present. This
represents a clinical judgment that sometimes is difficult to make. Some comments that
appear delusional may, in fact, be true. In contrast, some reports that initially seem
believable may be later identified as delusions as the symptoms worsen, the delusions
become less encapsulated (ie, begin to extend to more people or situations), and more
information comes to light. The clinical judgment that delusions are present should be
made after taking into account the degree of plausibility, systemization, and the possible
presence of culturally sanctioned beliefs that are different from one's own beliefs. Making
the distinction between a true observation, a firm belief, an overvalued idea, and a
delusion is sometimes a challenging task. Often, the extremeness and inappropriateness
of the patient's behaviors, rather than the simple truth or falsity of the belief, indicate its
delusional nature(Manschreck,1996;Fennig,2005).
The second step is determining the presence or absence of important characteristics often
associated with delusions, such as confusion, agitation, perceptual disturbances, physical
symptoms, and prominent mood abnormalities (which would point away from a diagnosis
of delusional disorder and toward other diagnoses) (Manschreck, 1996).
The third step is to present a systematic differential diagnosis. A thorough history, mental
status examination, and laboratory/radiologic evaluation should be performed to rule out
other medical and psychiatric conditions that are commonly present with delusions.
Delusional disorder should be seen as a diagnosis of exclusion (Manschreck, 1996).
Clinical presentation (Manschreck, 1999; Manschreck, 2000; Fennig, 2005)
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The mental examination is usually normal with exception of the presence of abnormal
delusional beliefs.
In general, patients are well groomed and well dressed without evidence of gross
impairment.
Speech, psychomotor activity, and eye contact may be affected by the emotional state
associated with delusions.
Mood and affect are consistent with delusional content; for example, patients with
persecutory delusions may be suspicious and anxious. Mild dysphoria may be present
without regard of type of delusions.
Tactile and olfactory hallucinations may be present and may be prominent if they are
related to the delusional theme (eg, the sensation of being infested by insects, the
perception of body odor). Medical causes of tactile and olfactory hallucinations, such as
substance intoxication and withdrawal, temporal lobe epilepsy, and others, should be
ruled out. Auditory or visual hallucinations are uncommon but, if present, they are not
prominent.
The thought content is notable for systematized, well-organized, nonbizarre delusions that
are possible to occur, such as delusions of being persecuted, being loved by a person of
higher status, being infected, having an unfaithful spouse, and others. Delusional
concepts may be complex or simple, but bizarre beliefs such as delusions of thought
insertion, and thought control are more common in schizophrenia. Contrary to
schizophrenia, the thought process is usually not impaired; however, some
circumstantiality and idiosyncrasy may be observed.
Memory and cognition are intact. Level of consciousness is unimpaired.
Patients usually have little insight and impaired judgment regarding their pathology.
Police, family members, coworkers, and physicians other than psychiatrists are usually
the first to suspect the problem and seek psychiatric consultation. Seeking corroborative
information, when permitted by the patient, is often crucial.
Assessment of homicidal or suicidal ideation is extremely important in evaluating patients
with delusional disorder. The presence of homicidal or suicidal thoughts related to
delusions should be actively screened for and the risk of carrying out violent plans should
be carefully assessed. Reid (2005) pointed out that some types of this illness—
erotomanic, jealous, and persecutory—are associated with higher risk for violence than
others (Reid, 2005). History of previous violent acts as well history of how aggressive
feelings were managed in the past may help to assess the risk.
Presentation of the subtypes
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Erotomanic type
o Related terms include erotomania, psychose passionelle, Clerambault syndrome,
and old maid's insanity (Manschreck, 2000; Fennig, 2005; Kelly, 2005).
o The central theme of delusions is that another person, usually of higher status, is
in love with the patient. The object of delusion is generally perceived to belong to
a higher social class, being married, or otherwise unattainable (Munro, 1999;
Kelly, 2005).
o Patients with this type of delusion are generally female, although males
predominate in forensic samples (APA, 2000; Kelly, 2005).
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Delusional love is usually intense in nature. Signs of denial of love by the object
of the delusion are frequently falsely interpreted as affirmation of love
(Manschreck, 2000; Kelly, 2005).
o Patients may attempt to contact the object of the delusion by making phone calls,
sending letters and gifts, making visits, and even stalking. Some cases lead to
assaultive behaviors as a result of attempts to pursue the object of delusional
love or attempting to "rescue" her/him from some imagined danger (APA, 2000).
Grandiose type
o Patients believe that they possess some great and unrecognized talent, have
made some important discovery, have a special relationship with a prominent
person, or have special religious insight (APA, 2000).
o Grandiose delusions in the absence of mania are relatively uncommon, and the
distinction of this subtype of disorder is debatable. Many patients with paranoid
type show some degree of grandiosity in their delusions (Fennig, 2005).
Jealous type
o Related terms include conjugal paranoia, Othello syndrome, and pathological or
morbid jealousy (Manschreck, 1999; Sadock, 2003).
o The main theme of the delusions is that her or his spouse or lover is unfaithful.
Some degree of infidelity may occur; however, patients with delusional jealousy
support their accusation with delusional interpretation of "evidence" (eg,
disarrayed clothing, spots on the sheets) (APA, 2000; Fennig, 2005).
o Patients may attempt to confront their spouses and intervene in imagined
infidelity. Jealousy may evoke anger and empower the jealous individual with a
sense of righteousness to justify their acts of aggression. This disorder can
sometimes lead to acts of violence, including suicide and homicide (Fennig,
2005).
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Persecutory type
o Patients believe that they are being persecuted and harmed (Fennig, 2005).
o In contrast to persecutory delusions of schizophrenia, the delusions are
systematized, coherent, and defended with clear logic. No deterioration in social
functioning and personality is observed (Manschreck, 2000).
o Patients are often involved in formal litigation against their perceived persecutors.
Munro (1999) refers to an article by Freckelton who identifies the following
characteristics of deluded litigants: determination to succeed against all odds,
tendency to identify the barriers as conspiracies, endless drive to right a wrong,
quarrelsome behaviors, and "saturating the field" with multiple complaints and
suspiciousness (Munro, 1999).
o Patients often experience some degree of emotional distress such as irritability,
anger, and resentment (Fennig, 2005). In extreme situations, they may resort to
violence against those who they believe are hurting them (APA, 2000)
o The distinction between normality, overvalued ideas, and delusions is difficult to
make in some of the cases (Fennig, 2005).
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Somatic type
o Related terms include monosymptomatic hypochondriasis (Fennig, 2005).
o The core belief of this type of disorder is delusions around bodily functions and
sensations. The most common are the belief that one is infested with insects or
parasites, the belief of emitting a foul odor, the belief that parts of the body are
not functioning, and the belief that their body or parts of the body are misshapen
or ugly (APA, 2000).
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Patients are totally convinced in physical nature of this disorder, which is contrary
to patients with hypochondriasis who may admit that their fear of having a
medical illness is groundless (Manschreck, 2000).
o Patients are usually first seen by dermatologists, cosmetic surgeons, urologists,
gastroenterologists, and other medical specialists (Fennig, 2005).
o Sensory experiences associated with this illness (eg, sensation of parasites
crawling under the skin) are viewed as components of systemized delusions
(Fennig, 2005).
Mixed type
o Patients exhibit more than one of the delusions simultaneously (Fennig, 2005),
and no one delusional theme predominates (APA, 2000).
Unspecified type
o Delusional themes fall outside the specific categories or cannot be clearly
determined (APA, 2000).
o Misidentification syndromes such as Capgras syndrome (characterized by a
belief that a familiar person has been replaced by an identical impostor) or Fregoli
syndrome (a belief that a familiar person is disguised as someone else) fall into
this category. Misidentification syndromes are rare and frequently are associated
with other psychiatric conditions (eg, schizophrenia) or organic illnesses (eg,
dementia, epilepsy) (Fennig, 2005).
o Another unusual syndrome is Cotard syndrome, in which patients believe that
they have lost all their possessions, status, and strength as well as their entire
being, including their organs (Fennig, 2005). Described first in the 19th century, it
is a rare condition, which is usually considered a precursor to a schizophrenic or
depressive episode (Manschreck, 2000).
Differential Diagnosis
Table 1. Medical Conditions Associated With Development of Delusions (Fenning et al, 2005)
Medical Conditions
Examples
Neurodegenerative
disorders
Alzheimer disease, Pick disease, Huntington disease, basal ganglia
calcification, multiple sclerosis, metachromatic leukodystrophy
Other CNS disorders
Brain tumors, especially temporal lobe and deep hemispheric tumors;
epilepsy, especially complex partial seizure disorder; head trauma
(subdural hematoma); anoxic brain injury; fat embolism
Vascular disease
Atherosclerotic vascular disease, especially when associated with
diffuse, temporoparietal, or subcortical lesions; hypertensive
encephalopathy; subarachnoid hemorrhage, temporal arteritis
Infectious disease
Human immunodeficiency virus/acquired immune deficiency
syndrome, encephalitis lethargica, Creutzfeldt-Jakob disease,
syphilis, malaria, acute viral encephalitis
Metabolic disorder
Hypercalcemia, hyponatremia, hypoglycemia, uremia, hepatic
encephalopathy, porphyria
Endocrinopathies
Addison disease, Cushing syndrome, hyperthyroidism or
hypothyroidism, panhypopituitarism
Vitamin deficiencies
Vitamin B-12 deficiency, folate deficiency, thiamine deficiency, niacin
deficiency
Medications
Adrenocorticotropic hormones, anabolic steroids, corticosteroids,
cimetidine, antibiotics (cephalosporins, penicillin), disulfiram,
anticholinergic agents
Substances
Amphetamines, cocaine, alcohol, cannabis, hallucinogens
Toxins
Mercury, arsenic, manganese, thallium
Delusional symptoms are preferentially associated with disorders involving the limbic system and
basal ganglia (Fennig, 2005).
Fifty percent of patients with Huntington disease and individuals with idiopathic basal ganglia
calcifications developed delusions at some point of their illness (Fennig, 2005).
Head trauma has been associated with development of delusions. Koponen et al (2002) found
patients with traumatic brain injury were diagnosed with delusional disorder in 5% of the cases
during a 30-year follow-up (3 out of 60 assessed patients).
Table 2. Disorders and Differentiating Features
Disorder
Differentiating Features
Delirium
Fluctuating level of consciousness and impaired cognition are
features of delirium that are absent in delusional disorder.
Dementia
Delusions (usually persecutory) are common in Alzheimer and
other types of dementia (the prevalence ranges from 15-50%)
and may present first, before cognitive deficits become
apparent. Neuropsychological testing may be warranted to
detect cognitive impairments. Additionally, elderly patients with
delusional disorder were found to have an incidence of
dementia that was twice as high as the general population's in
a 10-year follow-up period (Leinonen, 2004).
Substance-related disorders
(intoxication, withdrawal,
substance-induced
psychotic disorder with
delusion)
Amphetamines and cocaine are the most commonly described
substances to be associated with delusions, typically of
persecutory type. Other illicit drugs (especially hallucinogens,
anabolic steroids) and alcohol have been related to the
development of delusions. (For example, alcohol withdrawal is
a common condition, which may present with tactile or somatic
delusions). Prescribed substances (especially steroids,
dopamine agonists), OTC medications (especially
sympathomimetics), and herbal products may also be
associated with delusions. Careful substance and medication
use history with specific attention to temporal relationship
between substance use and onset/persistence of delusional
symptoms may aid in differential diagnosis.
Mood disorders with
delusional symptoms
(manic or depressive type)
Mood symptoms are common in persons with delusional
disorder and often represent an appropriate emotional
response to perceived delusional experiences. However, given
that mood disorders are common in the general population,
they may present as comorbid conditions, often predating
delusional disorder. Mood symptoms of mood disorders
contrary to mood symptoms of delusional disorder are
prominent and meet criteria for a full mood episode
(depressive, manic, or mixed). Delusions associated with mood
disorders usually develop after the onset of mood symptoms
and progress secondary to mood abnormalities. Mood
symptoms of delusional disorder are generally mild and
delusions usually exist in the absence of mood abnormalities.
Schizophrenia
Delusions of schizophrenia are bizarre in nature, and
hallucinations are common. Additionally, disorganized thought
process, speech, or behaviors is present. Negative symptoms
and deterioration in function are prominent. Cognitive deficits
are common.
Hypochondriasis
Patients with hypochondriasis are usually able to doubt (at
least for a short while) their convictions of having illness when
presented with reassuring data. Most of them have a long
history of preoccupation, and their fears are usually not limited
to a single symptom or organ system.
Body dysmorphic disorder
(BDD)
Many patients with BDD hold their beliefs with conviction that
reaches level of delusions, leading to a significant overlap
between these conditions.
Obsessive-compulsive
disorder (OCD)
Patients with OCD show a varying degree of insight into their
obsessions and compulsions. If reality testing is lost and
conviction in their beliefs reaches the level of delusions, both
disorders may be present.
Paranoid personality
disorder
Differentiation between extreme suspiciousness and frank
delusions may be difficult. History of pervasive distrust
beginning by early adulthood is suggestive of personality
disorder, while the delusional disorder most commonly
presents as an acute illness of middle life. Additionally, patients
with paranoid personality disorder frequently appear to be
unemotional and lack warmth in their relationships.
Shared psychotic disorder
Symptoms emerge in the context of a close relationship with
another person with delusional beliefs and diminish with
separation from that other person.
Treatment
General considerations
Delusional disorder is challenging to treat for various reasons, including patients' frequent denial
that they have any problem, especially of a psychological nature, difficulties in developing a
therapeutic alliance, and social/interpersonal conflicts.
Careful assessment and diagnosis are crucial because delusions commonly represent an
underlying organic illness that warrants specific treatment. Additionally, coexisting psychiatric
disorders should be recognized and treated accordingly.
Treatment of delusional disorder often involves both psychopharmacology and psychotherapy.
Given the chronic nature of this condition, treatment strategies should be tailored to the individual
needs of the patients and focus on maintaining social function and improving quality of life.
Establishing a therapeutic alliance, establishing acceptable symptomatic treatment goals, and
educating the patient's family are of paramount importance. Avoiding direct confrontation of the
delusional symptoms enhances the possibility of treatment compliance and response.
Hospitalization should be considered if a potential for harm or violence exists. Otherwise,
outpatient treatment is preferred.
Psychopharmacological treatment
Limited data exist on the psychopharmacological treatment of delusional disorder. Most of the
available information is based on case reports or small collection studies. No controlled studies
have been published up to date. As such, evidence for the psychopharmacological treatment of
delusional disorder would commonly be considered "grade C" (case series) or "grade D" (single
case studies) evidence in many evidence-based medicine hierarchies, as opposed to randomized,
blinded studies (grade A) or nonrandomized or nonblinded, but still systematically conducted,
studies (grade B). (For example, see the Center for Evidence-Based Medicine guidelines).
Antipsychotics have been used since the seventies when the first report was published on the use
of pimozide for the treatment of monosymptomatic hypochondriacal psychosis (now classified as
the delusional disorder, somatic type by DSM-IV-TR). Several case reports that followed supported
its use. This medication continues to be cited as a preferential treatment for this disorder in
literature. In 1995, Munro and Mok published a review of the treatment data published between
1965 and 1985 of approximately 1000 cases. They analyzed 257 cases and found that the body of
evidence is limited and confusing. Nevertheless, they concluded that delusional disorder has a
relatively good prognosis when adequately treated: 52.6% of the patients recovered, 28.2%
achieved partial recovery, and 19.2% did not improve. Additionally, they reported that treatment
response was positive regardless of the specific delusional content. They found that pimozide
showed the strongest evidence of response compared with other
typical antipsychotics: 68.5% recovery rate and 22.4% partial recovery rate were found in
pimozide-treated cases and 22.6% recovery and 45.3% partial recovery were found in cases
treated by other typical antipsychotics.
Since then, new data have been accumulated, but the data still consist only of case reports. The
most recent review of treatment for delusional disorder Manschreck and Khan (2006) analyzed
224 additional case reports published since 1995, and they summarized 134 case reports that
provided sufficiently detailed information about treatment. The following is the summary of their
findings:
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In general, delusional disorders were reported to be fairly responsive to treatment (50% of
the published patients reported symptom-free recovery and 90% of patients showed at
least some improvement). Polypharmacy was common, most often including a
combination of antipsychotic and antidepressant medication. In addition, patients
commonly received more than one antipsychotic over the course of their illness, and
medication treatments were also complemented by other interventions, such as cognitivebehavioral therapy or even (in a single case) ECT.
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In contrast to previous findings, no significant difference was observed between treatment
with pimozide and with other antipsychotics. In addition, no difference was observed
between typical and atypical antipsychotic agents. The authors did identify that somatic
delusions appeared potentially more responsive to antipsychotic therapy than other types
of delusions (regardless of whether this treatment was pimozide or other antipsychotics).
However, this difference may result from the generally poor response rates (50%
improvement rates, with no reports of complete recovery) observed for the few case
reports of treatment of delusional disorder with persecutory delusions.
Four reports (5 cases) of individuals with delusions presumably refractory to previous
antipsychotic treatment reported that clozapine was associated with an improved quality
of life and a decrease in symptoms associated with the delusion, although the central
delusional theme often persisted.
Antidepressants have been successfully used for the treatment of delusional disorder, although
primarily of the somatic type. The data consist of case reports showing improvement with SSRI
(Hayashi, 2004) and clomipramine treatments (Sondheimer, 1988; Wada, 1999). Several case
reports documented successful treatment with SSRI for culture-bound syndromes (conditions that
would be diagnosed as somatic type of delusional disorder in Western cultures) (Nagata, 2006). A
single case report of successful ECT use for somatic delusions exists (Ota, 2003).
Review of treatment of delusional disorder have not systematically addressed the question of what
dose of antipsychotic is not typically sufficient to achieve remission of symptoms; however, one
study (Morimoto, 2002) did note that their 11 patients with delusional disorder appeared to be
adequately treated on fairly low doses of antipsychotic (4.7 mg of haloperidol). In contrast, as
indicated above (Manschreck and Khan, 2006), some cases of delusional disorder appear
refractory even to clozapine treatment.
In summary, a reasonable pharmacological treatment approach for the patient with delusional
disorder is a standard trial of an antipsychotic or, for somatic delusions, SSRI at starting doses
commonly used to treat psychotic or mood disorders.
Psychotherapy
For most patients with delusional disorder, some form of supportive therapy is helpful. The goals of
supportive therapy include facilitating treatment adherence and providing education about the
illness and its treatment. Educational and social interventions can include social skills training (eg,
not discussing delusional beliefs in social settings) and minimizing risk factors, including sensory
impairment, isolation, stress, and precipitants of violence. Providing realistic guidance and
assistance in dealing with problems stemming from the delusional system may be very helpful
(Fochtmann, 2005).
Cognitive therapeutic approaches may be useful for some patients. The therapist helps the patient
to identify maladaptive thoughts by means of Socratic questioning and behavioral experiments,
and then to replace them with alternative, more adaptive beliefs and attributions. Discussion of the
unrealistic nature of delusional beliefs should be done gently and only after rapport with the patient
has been established (Silva, 2003; Fochtmann, 2005; Turkington, 2006).
Some authors believe that insight-oriented therapy is rarely indicated (Forchtmann, 2005) or even
contraindicated (Manschreck, 2000). However, reports exist of successful treatment (Silva, 2003).
Goals in insight-oriented therapy include development of the therapeutic alliance; containing
projected feelings of hatred, badness, and impotence; measured interpretation; and, ultimately,
developing a sense of creative doubt in the internal perception of the world through empathy with
the patient's defensive position (Silva, 2003).
Principal sources for this review include American Psychiatric Association, 2000, DSM-IV-TR; the
chapters by Manschrek and Fenning in Kaplan and Sadock's Comprehensive Textbook of
Psychiatry (7th and 8th eds, respectively); the chapter by B.J. Sadock in Kaplan and Sadock's
Synopsis of Psychiatry (9th ed); and Delusional disorder: paranoia and related illness by Munro,
1999; as well as the seminal treatment reviews by Munro and Mok, 1995, and Manschrek and
Khan, 2006. Citations to original literature included when these citations could be confirmed, or
occasionally by referencing a secondary, more recent source citing the original literature when the
original report was not available. Specific references cited are provided below.
Patient and family education
Often the treatment approach covers patient education, but educating the family about the
symptoms and course of the disorder is also useful. This is especially true since the family
frequently feels the impact of the disorder the most.