Malingering in the Primary Care Setting. Jeremy Di Bari, DVM, MD M elissa Arthur, PhD

Transcription

1 Malingering in the Primary Care Setting Jeremy Di Bari, DVM, MD M elissa Arthur, PhD

2 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 (M unchausen Syndrome) Illness falsification WITHOUT external rewards Accept invasive testing

3 Factitious Disorder Syndrome derives from Baron M unchausen 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 M unchausen s stories M unchausen Syndrome refers to the most severe form of Factitious Disorder

4 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.

5 Causes of Malingering Criminal prosecution Military service Workers Compensation Desire for Drugs/Substances

6 Features of Malingering H istory 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 M edical-legal context

7 General Categories Pure Non-existent clinical problems Feigned Partial physical signs that are exaggerated False Imputation Deliberate misattribution of actual symptoms

8 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

9 DSM V Recommendations for Suspecting Malingering M edico-legal context of presentation M arked 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

10 Physical Exam Typically not consistent with history Patient s attitude may be vague Occasionally, patients can become irritable or hostile

11 Objective Examination M innesota M ultiphasic Personality Inventory Test of M emory M alingering 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

12 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

13 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

14 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

15 Objective evidence of TBI 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

16 fmri Functional M RI 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 M ust be interpreted with caution 84% sensitive, 88% specific with the Wada Test Not yet useful for surgical treatment planning/targeting

17 Utility of fmri to detect Malingering 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

18 Procedure for fmri comparison Test of M emory M alingering 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 M VA with subsequent memory impairment Told not to obviously feign responses, however

19 Normal vs Malingered Responses

20 fmri in a Legal Setting May not discriminate reliably Problem of interference between different areas of the brain Countermeasures confound imaging results

21 fmri in Court Wilson vs Corestaff Services, LP ( 2010) Plaintiff wanted to use fm RI results to increase the credibility of a main witness Court held that the fm RI 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

22 fmri in Court, Continued United States vs Semrau (2010) Case regarding M edicare Fraud Patient underwent three rounds of fmri testing due to invalid results, fatigue, etc Judge found that there was little consistency of fm RI results, or even known error rates, OUTSIDE of the laboratory Also troubled by the repeated tests Semrau was convicted, but appealed th Circuit Court of Appeals upheld the ruling and the decision to NOT allow the fmri results

23 fmri in Court, Continued fmri findings consistent with psychopathy Defense tried to use this as a loophole, but were unsuccessful Brian Dugan

24 Differential Diagnosis Depression Panic Disorder Substance use disorder Non-psychiatric disorder

25 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 M edicolegal settings may involve a neuropsychologist Often find that validity tests show worse function in patients with mild TBI compared to moderatesevere brain injury, especially in patients seeking compensation

26 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

27 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

28 References Bienenfeld, David, et al. "M alingering clinical presentations." Emedicine. medscape. com/article/ clinical. Bass, Christopher, and Peter H alligan. "Factitious disorders and malingering: challenges for clinical assessment and management." The Lancet (2014): Weiss, Kenneth J., and L. Dell Van. "Liability for Diagnosing M alingering." The journal of the American Academy of Psychiatry and the Law 45.3 (2017): American Psychiatric Association. Diagnostic and Statistical M anual of M ental Disorders, Fifth Edition ( DSM -5), American Psychiatric Association, Arlington 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 P.609.

29 References Browndyke, Jeffrey N. et al. Neuroanatomical Correlates of M alingered M emory Impairment: Event-Related fm RI of Deception on a Recognition M emory Task. Brain injury : [ BI] 22.6 (2008): PM C. Web. 1 Feb Bar-H en, M oran, 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 (2015): The M acarthur Foundation Research Network on Law and Neuroscience / fm RI AND LIE DETECTION / American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing.