Download Differentiating Somatoform Disorder, Factitious Disorder and

Differentiating Somatoform Disorder,
Factitious Disorder and Malingering
Practical Strategies Conference
June 11, 2015
Dr. William H. Gnam, PhD, MD, FRCPC
Psychiatrist
[email protected]
Outline
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Introduction: The diagnostic methods of psychiatry
Clinical Descriptions and Essential Features
Diagnostic Criteria: DSM-IV vs. DSM-5
The Changing Conception of Conversion Disorder
Factitious Disorder: updated diagnostic criteria
• Malingering and motivation
• Practical Strategies for Differentiating
• Conclusions
Introduction (1)
• The Diagnostic Manuals for Mental Disorders
emphasize standardized, reproducible methods
• Diagnoses are confirmed on the basis of
symptoms (primarily), signs (secondarily)
• Emphasis on reportable or observable criteria is
intended to increase objectivity and
reproducibility
Introduction (2)
• In North America, the dominant diagnostic
system is the Diagnostic and Statistical Manual of
Mental Disorders (DSM), 1st through 5th editions
• Diagnoses are defined according to specific
diagnostic criteria, with rules for necessary and
sufficient criteria
• The most valuable property of the DSM system is
the potential to provide reliable (reproducible)
diagnoses
Introduction (3)
• For many important diagnoses in the DSM-IV,
(e.g. Major Depressive Disorder), good
reliability has been established scientifically
• With the DSM-5, less reliability data, some
evidence that important diagnoses lack
acceptable reliability
Introduction (4)
• In contrast with the “rational” methods for
diagnosis of many mental disorders,
confirming the diagnoses of Conversion,
Factitious Disorder and Malingering requires:
– Difficult exclusions (Conversion Disorder)
– Inferences based upon external data, not
exclusively patient self-report
– Very difficult judgments about motivation
Conversion Disorder (1)
• Essential features are:
– The presence of symptoms or deficits affecting voluntary motor
or sensory functioning
– The symptoms or deficits cannot be fully explained by a
neurological or general medical condition – and are
incompatible with a neurological condition or disease
– The symptoms/deficits typically do not conform to anatomical
pathways or physiological mechanisms, and may not be
consistent
Conversion Disorder (2)
• Estimates of the prevalence of Conversion
Disorder: from 11/100,000 to 500/100,000
• Onset is generally (but not exclusively) acute
• Recurrence is common: 25% within the first year
• Risk factors: maladaptive personality traits,
history of childhood abuse/neglect, stressful life
events (not always present)
Conversion Disorder (3)
• There were problems with the diagnosis of
Conversion Disorder defined in DSM-IV:
– Required confirmation that psychological factors
contributed, but factors were poorly defined and
not always present
– Required confirmation that feigning / intentional
symptom production is excluded, but such
exclusions are often not reliable
Conversion Disorder (4)
• The DSM-5 represents a major revision of the
diagnostic criteria for Conversion Disorder
Conversion Disorder(5):
Major Changes in Diagnostic Criteria
DSM - IV
• One or more symptoms or
deficits affecting voluntary
motor or sensory function
that suggest a neurological
disorder/general medical
condition symptom(s)
• The symptom cannot be
fully explained by a general
medical condition
DSM - 5
• One or more symptoms of
altered motor or sensory
function
• Evidence of incompatibility
between the symptom and
recognized neurological
conditions
Conversion Disorder(6):
Major Changes in Diagnostic Criteria
DSM - IV
DSM - 5
• Psychological factors are
judged to be associated
with the symptom or deficit
• (This criterion dropped)
• The symptom or deficit is
not intentionally produced
or feigned
• (Dropped.) The symptom or
deficit is not better
explained by another
medical or mental disorder
Conversion Disorder (7)
• The revised criteria have major practical
implications:
– More emphasis on eliciting medical evidence of
incompatibility with known neurological conditions
– The onerous requirement to exclude feigning is dropped
(but still must consider a better explanation)
– Dropped requirement for associated psychological factors,
consistent with empirical studies
Conversion Disorder (8)
• Another very important implication/
acknowledgement:
– “The diagnosis of conversion disorder does not
require the judgment that the symptoms are not
intentionally produced (i.e., not feigned), as the
definitive evidence of feigning may not be reliably
discerned” (DSM-5, page 320)
Factitious Disorder (1)
• Essential Features:
– Intentional production or feigning of physical or
psychological symptoms
– External incentives (such as economic gain, avoiding
legal responsibilities) are absent
– (The motivation for the behaviour is to assume the
sick role.)
Factitious Disorder (2)
• There is very limited evidence on prevalence, but
factitious disorders are very rare
• In large general hospitals, about 1% of inpatients
for whom there is psychiatric consultation are
diagnosed are diagnosed with Factitious Disorder
• Onset usually in early adulthood, course
characterized by (repeated) intermittent
episodes, often after hospitalization for a general
medical condition or psychiatric disorder
Factitious Disorder (3)
• Published case series suggest a strong
association with severe dysfunctional
personality characteristics
• The intentional production of symptoms or
feigning can mimic a wide range of medical
conditions or psychological symptoms, not
just motor or sensory symptoms/deficits
Factitious Disorder (4)
• What limited data that exists suggests that
persons with Factitious Disorder do not
experience their motive to be the need to
assume the sick role
• The DSM-5 contains a significant revision of
the diagnostic criteria for Factitious Disorder:
Factitious Disorder(5):
Changes in Diagnostic Criteria
DSM - IV
DSM - 5
• Intentional production or
feigning of physical or
psychological signs or
symptoms
• Falsification of physical or
psychological signs or
symptoms, or induction of
injury or disease, associated
with identified deception
• The motivation for the
behaviour is to assume the
sick role
• (Dropped as a criterion: but
stipulates that behaviour is
not better explained by
another mental disorder)
Factitious Disorder(6):
Changes in Diagnostic Criteria
DSM - IV
DSM - 5
• External incentives for the
behaviour (such as
economic gain, etc.) are
absent
• The deceptive behaviour is
evident even in the absence
of obvious external
incentives
• (Not explicitly stated)
• The individual presents
himself or herself to others
as ill, impaired, or injured
Factitious Disorder (7)
• The revised criteria have some practical
implications:
– More emphasis on the objective identification of
falsification of signs and symptoms of illness, rather than
inference about intent or possible underlying motivation.
– The revised criteria do not imply that factitious disorder
behaviours could never occur in the presence of external
incentives, but does stipulate that they persist even when
obvious external rewards/incentives are absent.
Malingering (1)
• Malingering is a massive topic and not the focus
of the current presentation
• Malingering has never been considered to be a
mental disorder
• The essential feature of Malingering definitions is
the intentional production of false or grossly
exaggerated physical or psychological symptoms,
motivated by external incentives
Malingering (2)
• The limited data on Malingering indicates that
the prevalence is not high, but from a societal
perspective the prevalence is nonetheless
significant
• The definition of Malingering has not changed
significantly between the DSM-IV and DSM-5.
Malingering (3)
• Despite the attempts of the DSM-5 to remove
criteria that require inference about motivation,
the DSM-5 description of Malingering emphasizes
that the motivation for the symptom production
is an external incentive
• The difficulties in determining motives
acknowledged in other disorders are no easier in
Malingering
Malingering (4)
• There are difficulties with the DSM and other
discussions of Malingering:
• Failure to distinguish between other
motivation for conscious symptom
production/exaggeration (e.g., “cry for help”)
• Lack of acknowledgement of the difficulties in
determining motivation clinically
Differentiating: Practical Strategies (1)
• The changes in diagnostic criteria correctly imply
that clinical assessment should focus on
accurately identifying behaviours, and gathering
evidence about incompatibility with medical
conditions, and not should not speculate/infer
motive
• This change does not imply that differentiating
between Conversion, Factitious Disorder and
Malingering (or other conscious symptom
production) is not possible in many cases
Differentiating: Practical Strategies (2)
• Factitious Disorder can be excluded in most cases
involving disability after acute traumatic injury
(MVAs, work accidents), because
– Factitious Disorders are very rare
– They can involve behaviours that produce nonconversion symptoms
– They become manifest mostly in inpatient settings
– The natural history is repeated episodes over time,
usually established before a traumatic event
– They do not occur repeatedly or predominantly with
obvious external incentives
Differentiation: Practical Strategies (3)
• Distinguishing between “Malingering” and
Conversion Disorder based upon a single clinical
encounter is difficult or impossible, but this
should not preclude a “working” diagnosis of
Conversion Disorder in cases of genuine
uncertainty
• Malingering vs. Conversion cannot be reliably
distinguished by minor inconsistencies in the
symptom/deficit, as such inconsistencies are
common to both
Differentiation: Practical Strategies (4)
• Distinguishing between Conversion vs.
“Malingering” cannot be reliably
accomplished by identification of external
incentives or risk factors, as none are sensitive
or specific enough to discriminate reliably
Differentiation: Practical Strategies (5)
• Distinguishing between Conversion vs.
“Malingering” is best accomplished with
longitudinal clinical data provided by extensive
documentation review, by collateral examination
for symptom production (such as
neuropsychological testing), and by repeated
observations
• However, in some cases uncertainty is inevitable
and may persist for years or indefinitely
Summary (1)
• The diagnoses of Factitious Disorder, Conversion
and Malingering have often been unreliable due
to inference / speculation about motive
• Major changes in the diagnostic criteria for
Conversion Disorder and Factitious Disorder
improve the practical procedures to make these
diagnoses by removing reference to motivation
Summary (2)
• Excluding Factitious Disorder is usually
straightforward in cases involving acute injury,
especially when external incentives are
persistently present, or when a history of
repeated disturbance while in hospital is absent
• There is no straightforward clinical method to
distinguish between Conversion Disorder and
Malingering, which is acknowledged for the first
time in the DSM-5.
Summary (3)
• While in many cases Conversion Disorder vs.
Malingering can be differentiated by the
consistency of evidence and presentation over
time, in some (rare) cases the uncertainty will
persist.
• The DSM and other discussions of Malingering
often involve unwarranted assumptions
regarding motivation that are likely simplistic