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Malingering in the Primary Care Setting
Jeremy Di Bari, DVM, MD Melissa Arthur, PhD
Simulation of Illness ● Both malingering and factitious disorder involve simulating an illness ● Malingering
○ Illness falsification for external benefits ○ Money, medications, time off, etc… ○ Decline invasive testing
● Factitious Disorder (Munchausen Syndrome) ○ Illness falsification WITHOUT external rewards ○ Accept invasive testing
Factitious Disorder ● Syndrome derives from Baron Munchausen
○ Literary character based on a German Nobleman ○ Told embellished stories of his adventures the Russo-Turkish War
● In 1951, Richard Asher attributed Factitious Disorder to Munchausen’s stories
● Munchausen Syndrome refers to the most severe form of Factitious Disorder
Epidemiology ● Understandably difficult to estimate ● Symptom exaggeration
○ Social Security disability exams in the US, 46-60% of claimants based on a symptom validity test
○ American Board of Clinical Neuropsychology estimates 29% for personal injury and 30% for disability compensation
Trend of insured workers claiming SSD over time. National Organization of Social Security
Claimant’s Representatives.
Causes of Malingering ● Criminal prosecution ● Military service ● Workers’ Compensation ● Desire for Drugs/Substances
Features of Malingering ● History of inconsistent and vague responses ● Obvious external benefit ● Conditional threats (“I’ll kill myself if you don’t admit me”) ● Inconsistencies between history and exam ● Using medical or technical terms ● Antisocial personality disorder ● Medical-Legal context
www.knowmedge.com
General Categories ● Pure
○ Non-existent clinical problems
● Feigned ○ Partial physical signs that are exaggerated
● False Imputation ○ Deliberate misattribution of actual symptoms
DSM V ● Intentional production of false or grossly exaggerated physical or psychological
symptoms with a goal to: ○ Military duty ○ Avoiding work ○ Financial compensation ○ Evading clinical prosecution ○ Obtaining drugs ○ Etc…
● Differs from factitious disorder because there is a goal of an external incentive ● Differs from conversion disorder and somatic-related mental disorders by the
intentional production of symptoms with goal of an external gain
DSM V Recommendations for Suspecting Malingering ● Medico-Legal context of presentation ● Marked discrepancy between individual’s claimed stress/disability and objective
findings ● Lack of cooperation or lack of complying with prescribed treatment regimen ● Presence of antisocial personality disorder
www.thehealthsite.com
Physical Exam ● Typically not consistent with history ● Patient’s attitude may be vague ● Occasionally, patients can become irritable or hostile
Objective Examination ● Minnesota Multiphasic Personality Inventory ● Test of Memory Malingering ● Portland Digit Recognition Test ● fMRI?
It should be noted that these tests examine memory and an individual's propensity to be feigning their response. Unfortunately, this is not useful for all cases of malingering.
These tests are generally administered by psychologists
Minnesota Multiphasic Personality Inventory ● Initially developed in the 1940’s ● Updated versions may be useful to detect
malingering ○ Utilizes validity scales for overreporting to
predict suspected malingering ○ Found to be useful, with a newer Restructured
form found to be improved compared to the original version
● Interpreted by a psychologist
Test of Memory Malingering ● 50 question visual memory recognition test, developed in 1996
○ Patients given a line drawing, then essentially must be able to recognize that they had seen the image before on a future trial
● Discriminates between true memory impairment and malingering ● Found to be relatively resistant to “coaching” for incorrect answers and
underlying depression
Portland Digit Recognition Test ● Detects an individual’s performance on a memory examination
○ Able to predict if the patient was choosing incorrectly on purpose vs actual memory impairment
● Evidence shows that objective testing can be helpful in determining true cases of TBI vs malingered cases ○ 2015 validated findings from cases of TBI in litigation
● First, patients were assessed for a Response Bias using the Test of Memory Malingering
● Then, patients were assessed using NeuroTrax ○ Assesses verbal/non-verbal memory, visuospatial processing, verbal function, motor skills and
executive function
● If patients show exaggeration in responses, they are more likely to be malingering ○ 87.5% sensitive and 98% specific, allowing authors to conclude 94% of cases can be classified
correctly between feigned and true responses
Objective evidence of TBI
fMRI ● Functional MRI detects difference in blood flow and
oxygenation ○ Utilized Blood-Oxygen-Level-Dependent (BOLD) Effect
● Non-invasively map areas of the brain ○ May be used in the future to help plan epilepsy surgery
● Must be interpreted with caution ○ 84% sensitive, 88% specific with the Wada Test
● Not yet useful for surgical treatment planning/targeting
www.pbs.org
● Functional MRI ● There are anatomical differences in the area of the brain activated when
comparing true and malingered responses ○ Malingering associates with inferior parietal and superior temporal activity ○ True responses have more dorsomedial frontal activation
● Response time had associations as well ○ Malingered responses had more dorsomedial frontal, temporal and inferior parietal regions ○ Normal responses had greater inferior occipitotemporal and dorsomedial parietal activity
■ Greater reliance upon visual/attentional networks
Utility of fMRI to detect Malingering
Procedure for fMRI comparison ● Test of Memory Malingering was used, as well as a similar visual object stimuli set ● Image was presented, then five minutes passed and an image was again presented.
Individuals needed to determine if they had seen the new image before, or if it was new.
● Then, individuals went through an additional study but were told to respond as if they had an MVA with subsequent memory impairment ○ Told not to obviously feign responses, however
Normal vs Malingered Responses
fMRI in a Legal Setting ● May not discriminate reliably ● Problem of interference between different areas of the brain ● Countermeasures confound imaging results
fMRI in Court ● Wilson vs Corestaff Services, LP (2010) ● Plaintiff wanted to use fMRI results to increase the credibility of a main witness ● Court held that the fMRI results did not meet the standard for admissibility since
it was “novel” scientific evidence and would have “to be generally accepted in the field to which it belongs”
fMRI in Court, Continued ● United States vs Semrau (2010) ● Case regarding Medicare Fraud
○ Patient underwent three rounds of fMRI testing due to invalid results, fatigue, etc…
● Judge found that there was little consistency of fMRI results, or even known error rates, OUTSIDE of the laboratory ○ Also troubled by the repeated tests
● Semrau was convicted, but appealed ○ 2012 6th Circuit Court of Appeals upheld the ruling and the decision to NOT allow the fMRI
results
fMRI in Court, Continued ● fMRI findings consistent with “psychopathy” ● Defense tried to use this as a loophole, but were unsuccessful
Brian Dugan
Differential Diagnosis ● Depression ● Panic Disorder ● Substance use disorder ● Non-psychiatric disorder
Caring for the patient ● Confront the person indirectly ● Do not refer to specialists
○ Generally will not accept psychiatric referrals
● Brain injury ○ 15-30% of patients with mild TBI have ongoing non-specific symptoms
● Medicolegal settings may involve a neuropsychologist ○ Often find that validity tests show worse function in patients with mild TBI compared to moderate-
severe brain injury, especially in patients seeking compensation
Prognosis and Outcome ● If medicolegal, some patients improve after settlements
○ Less stress ○ Less involvement in adversarial system
● No established legal statutes for reporting a clear case of malingering
A word about Somatic Symptom Disorder ● DSM V changed Somatoform Disorders to Somatic Symptom Disorder
○ Somatoform Disorders included Somatization disorder, hypochondriasis, pain disorder and undifferentiated somatoform disorder
● 6 months of symptoms ○ Distressing somatic symptoms ○ Disruption of functioning ○ Excessive and disproportionate thoughts
● New in DSM V, SSD may now have a medical explanation
References ● Bienenfeld, David, et al. "Malingering clinical presentations." Emedicine. medscape. com/article/293206-clinical.
● Bass, Christopher, and Peter Halligan. "Factitious disorders and malingering: challenges for clinical assessment and
management." The Lancet 383.9926 (2014): 1422-1432.
● Weiss, Kenneth J., and L. Dell Van. "Liability for Diagnosing Malingering." The journal of the American Academy of
Psychiatry and the Law 45.3 (2017): 339-347.
● American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5),
American Psychiatric Association, Arlington 2013.
● Yutzy SH, Parish BS. Somatoform disorders. In: The American Psychiatric Publishing Textbook of Substance Abuse
Treatment, 4th ed, Galanter M, Kleber HD (Eds), American Psychiatric Publishing, Washington, DC 2008. P.609.
References ● Browndyke, Jeffrey N. et al. “Neuroanatomical Correlates of Malingered Memory
Impairment: Event-Related fMRI of Deception on a Recognition Memory Task.” Brain injury : [ BI] 22.6 (2008): 481–489. PMC. Web. 1 Feb. 2018.
● Bar-Hen, Moran, et al. "Empirically derived algorithm for performance validity assessment embedded in a widely used neuropsychological battery: validation among TBI patients in litigation." Journal of clinical and experimental neuropsychology 37.10 (2015): 1086-1097.
● The MacArthur Foundation Research Network on Law and Neuroscience / fMRI AND LIE DETECTION / 02.23.16. www.lawneuro.com
● American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.