Kaplan and Sadocks Comprehensive Textbook of Psychiatry, 11e

1909

Chapter 19. Factitious Disorder

EPIDEMIOLOGY Factitious Disorder Imposed on Self

and hyperthyroidism. ICD-11 no longer includes “compensation neurosis” as a related disorder, which in ICD-10 was defined as the exaggeration of physical symptoms that are due to a confirmed phys ical disorder, caused by the psychological state of the individual in which distress and anxiety about prolonged or progressive disability feature prominently. ICD-11 aligns with DSM-5 in its distinction between factitious disorder from malingering (QC30) as depending on the absence of external incentives or rewards. In reality, intent, motive, and awareness are difficult to discern for a clinician with only brief or intermittent interactions with a patient, and each of these occurs on a spectrum. Although the DSM-5 and the ICD-10 and 11 require exclusion of malingering to diagnose a facti tious disorder, these two conditions easily and frequently coexist: For example, patients who habitually gratify themselves in the sick role may discover that they can also receive disability payments concur rently or patients who initially fabricated illness to obtain narcotics for intoxication may continue to deceive even when such medica tions are no longer forthcoming. Similarly, factitious disorders can coexist, particularly over time, with unconsciously produced illness behaviors such as functional neurologic symptom disorder, somatic symptom disorder, and dis sociative disorders. This longitudinal shifting in the production and motivation of somatic symptoms and the difficulty in determining the exact contributors to any one behavior led to the categoriza tion of factitious disorders as a type of somatic symptom disorder in DSM-5. Seen from the perspective of somatic symptoms as an expression of emotional distress, factitious disorder patients and somatic symptom disorder patients are both “engagement seeking.” The evolution of factitious disorder nosology continues along several schools of thought. One perspective has argued for the greater incorporation of performance-validity and symptom-validity testing into diagnostic criteria. Another perspective put forth by Bass and colleagues argues that a person’s psychological and social milieu is a greater contributor to most factitious presentations than any spe cific psychiatric diagnosis. Third, neuroimaging studies on deception indicate the activation of distinct networks in individuals instructed to feign symptoms during functional magnetic resonance imaging (fMRI), hinting at the possible future use of such techniques to refine the diagnostic process. Despite these theoretical controversies, factitious disorder imposed on another, still known as Munchausen syndrome by proxy in the legal literature, is well recognized in the legal system. All 50 states require the reporting of factitious disorder imposed on a child to protective services as a form of child abuse. Adults who, by vir tue of a medical or psychiatric condition, are mentally or physically disabled or reliant on another individual for assistance with activities of daily living are also at risk for becoming victims of abuse via factitious disorder imposed on another. With recognition in the lay press and medical literature of adult dependents as potential victims of an individual with factitious disorder imposed on another, clini cians should be aware that required reporting also extends to older adult patients and to the developmentally delayed. Neither the DSM-5 nor the ICD-11 makes mention of variants of factitious disorder imposed on another, in which individuals impose their psychiatric disorders or emotional needs upon their children, dependents, spouses, or even entire communities. These phenomena can range from the mundane ( achievement by proxy ) to the mildly disruptive ( hypochondriasis by proxy resulting in repetitive pediatric visits and unnecessary tests without fabrication or induction of ill ness) to the psychologically damaging ( gaslighting ) and the physi cally harmful ( anorexia nervosa by proxy and malingering by proxy ).

The prevalence of factitious disorder is unknown, in part because of the role of deception in this population, but is estimated to be approximately 1% of the health care–seeking population. Estimates of prevalence are invariably skewed by methodologic limitations of the studies, such as the type of data studied (physician surveys, demographic databases), the study population and setting (hospital ward, outpatient subspecialist, disability office), small sample sizes, recall bias, and publication bias. Studies of specialists and disease specific tests appear to overestimate prevalence, likely because fac titious disorder patients are more likely to see subspecialists and undergo extensive testing, whereas large database studies and sys tematic reviews are likely to underestimate prevalence due to lack of clinician awareness. There is a large population of people who never present to medical care but engage in disease-simulating behavior, such as those who play the sick role with family, friends, coworkers, social service agencies, online communities, or veterinarians and thus would not be included in medical epidemiologic estimates. Online support groups, social media platforms, and the internet create ripe conditions for factitious disorder patients to garner attention, owing to the ease of creating false identities, lack of face-to-face interac tion, and the ability to broadcast to large sympathetic audiences. In Sutherland and Rodin’s 1990 study of patients referred to a psychiatric consultation service in a general hospital, 10 out of 1,288 patients met the criteria for factitious disorder, resulting in a prevalence of 0.8%. A review by Kocalevent et al. in 2005 of 18 studies reporting a prevalence of factitious disorder found estimates varied from a minimum of 0.032% to a maximum of 9.26%, with a weighted mean of 0.9%. In a 2012 occupational medicine clinic sam ple of 400 patients tested for maximum grip strength, 32 were found to be deceptive in their performance, but only 3 were diagnosed with factitious disorder (0.75%). Fliege et al., in 2007, surveyed 109 senior physicians from internal medicine, surgery, neurology, and dermatology for the estimated prevalence of ICD-10 factitious dis orders in their yearly practice. The mean estimated prevalence was 1.3%, the modal prevalence was 1%, and individual estimates ranged from 0.01% to 15%. In 2010, Swanson et al. surveyed 213 physi cians regarding their estimates of rates of patients with medically unexplained symptoms. Out of all 4,159 patients seen in 1 day by these physicians, only 1.5% of patients were diagnosed with either a somatoform or factitious disorder diagnosis, with the majority likely somatoform disorders. Psychiatric settings are somewhat less likely to engage factitious disorder patients: Bhugra et al. estimated psychiatric Munchausen syndrome at 0.5% of adult psychiatric admissions younger than the age of 65 years, based on four diagnoses of Munchausen syndrome out of 775 admissions. In a study of 4,500 visits to a psychiatric emergency room, only 7, or 0.15%, represented factitious disorder. Similarly, a 1994 study estimated the prevalence at 0.14% in a com munity sample. In a reflection of the overlap between somatic symp toms and factitiousness, Fliege prospectively followed 194 patients admitted to a psychosomatic unit and found 9.7% (19) manifested factitious illness behavior. Database studies yield significantly lower rates of factitious disor der. In 2013, the DSM-5 working group on factitious and somatoform disorders examined data from the National Hospital Discharge Sur vey to determine the assignment rate of various psychiatric disorders. Out of more than 3.8 million discharges tracked, a factitious disorder diagnosis was assigned in approximately 9 cases per 100,000, far

Copyright © 2025 Wolters Kluwer, Inc. Unauthorized reproduction of this content is prohibited.