03 - 13.3 Illness Anxiety Disorder

13.3 Illness Anxiety Disorder

REFERENCES Dimsdale JE, Creed F, Escobar J, Sharpe M, Wulsin L, Barsky A, Lee S, Irwin MR, Levenson J. Somatic symptom disorder: An important change in DSM. J Psychosom Res. 2013;75(3):223–228. Frances A. The new somatic symptom disorder in DSM-5 risks mislabeling many people as mentally ill. BMJ. 2013;346:f1580. Halder SL, Locke GR 3rd, Talley NJ, Fett SL, Zinsmeister AR, Melton LJ 3rd. Impact of functional gastrointestinal disorders on health-related quality of life: A population-based case-control study. Aliment Pharmacol Ther. 2004;19:233. Karvonen JT, Veijola J, Jokelainen J, Laksy K, Jarvelin M-R, Joukamaa M. Somatization disorder in the young adult population. Gen Hosp Psychiatry. 2004;26:9–12. Keefe FJ, Abernethy AP, Campbell LC. Psychological approaches to understanding and treating disease-related pain. Annu Rev Psychol. 2005;56:601–630. Matthews SC, Camacho A, Mills PJ, Dimsdale JE. The internet for medical information about cancer: Help or hindrance? Psychosomatics. 2003;44:100–103. Prior KN, Bond MJ. Somatic symptom disorders and illness behaviour: Current perspectives. Int Rev Psychiatry. 2013;25(1):5–18. Rief W, Martin A. How to use the new DSM-5 somatic symptom disorder diagnosis in research and practice: a critical evaluation and a proposal for modifications. Annu Rev Clin Psychol . 2014;10:339–67. Sirri L, Fava GA. Diagnostic criteria for psychosomatic research and somatic symptom disorders. Int Rev Psychiatry. 2013;25(1):19–30. Smith TW. Hostility and health: Current status of psychosomatic hypothesis. In: Salovey P, Rothman AJ, eds. Social Psychology of Health. New York: Psychology Press; 2003:325–341. Somashekar B, Jainer A, Wuntakal B. Psychopharmacotherapy of somatic symptoms disorders. Int Rev Psychiatry. 2013;25(1):107–115. Tomenson B, Essau C, Jacobi F, Ladwig KH, Leiknes KA, Lieb R, Meinlschmidt G, McBeth J, Rosmalen J, Rief W, Sumathipala A, Creed F, EURASMUS Population Based Study Group. Total somatic symptom score as a predictor of health outcome in somatic symptom disorders. Br J Psychiatry. 2013;203(5):373–380. 13.3 Illness Anxiety Disorder Illness anxiety disorder is a new diagnosis in the fifth edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) that applies to those persons who are preoccupied with being sick or with developing a disease of some kind. It is a variant of somatic symptom disorder (hypochondriasis) described in Section 13.2. As stated in DSM-5: Most individuals with hypochondriasis are now classified as having somatic symptom disorder; however, in a minority of cases, the diagnosis of illness anxiety disorder applies instead. In describing the differential diagnosis between the two, according to DSM-5, somatic symptom disorder is diagnosed when somatic symptoms are present, whereas in illness anxiety disorder, there are few or no somatic symptoms and persons are “primarily concerned with the idea they are ill.” The diagnosis may also be used for persons who do, in fact, have a medical illness but whose anxiety is out of proportion to their diagnosis and who assume the worst possible outcome imaginable.

EPIDEMIOLOGY The prevalence of this disorder is unknown aside from using data that relate to hypochondriasis, which gives a prevalence of 4 to 6 percent in a general medical clinic population. In other surveys, up to 15 percent of persons in the general population worry about becoming sick and incapacitated as a result. One might expect the disorder to be diagnosed more frequently in older rather than younger persons. There is no evidence to date that the diagnosis is more common among different races or that gender, social position, education level, and marital status affect the diagnosis. ETIOLOGY The etiology is unknown. The social learning model described for somatic symptom disorder may apply to this disorder as well. In that construct, the fear of illness is viewed as a request to play the sick role made by someone facing seemingly insurmountable and insolvable problems. The sick role offers an escape that allows a patient to be excused from usual duties and obligations. The psychodynamic school of thought is also similar to somatic symptom disorder. Aggressive and hostile wishes toward others are transferred into minor physical complaints or the fear of physical illness. The anger of patients with illness anxiety disorder, as in those with hypochondriasis, originates in past disappointments, rejections, and losses. Similarly, the fear of illness is also viewed as a defense against guilt, a sense of innate badness, an expression of low self-esteem, and a sign of excessive self-concern. The feared illness may also be seen as punishment for past either real or imaginary wrongdoing. The nature of the person’s relationships to significant others in his or her past life may also be significant. A parent who died from a specific illness, for example, might be the stimulus for the fear of developing that illness in the offspring of that parent. The type of the fear may also be symbolic of unconscious conflicts that are reflected in the type of illness of which the person is afraid or the organ system selected (e.g., heart, kidney). DIAGNOSIS The major DSM-5 diagnostic criteria for illness anxiety disorder are that patients be preoccupied with the false belief that they have or will develop a serious disease and there are few if any physical signs or symptoms (Table 13.3-1). The belief must last at least 6 months, and there are no pathological findings on medical or neurological examinations. The belief cannot have the fixity of a delusion (more appropriately diagnosed as delusional disorder) and cannot be distress about appearance (more appropriately diagnosed as body dysmorphic disorder). The anxiety about illness must be incapacitating and cause emotional distress or impair the patient’s ability to function in important areas of life. Some persons with the disorder may visit physicians (careseeking type) while others may not (care-avoidant type). The majority of patients, however, make repeated visits to physicians and other health care providers.

Table 13.3-1 DSM-5 Diagnostic Criteria for Illness Anxiety Disorder CLINICAL FEATURES Patients with illness anxiety disorder, like those with somatic symptom disorder, believe that they have a serious disease that has not yet been diagnosed, and they cannot be persuaded to the contrary. They may maintain a belief that they have a particular disease or, as time progresses, they may transfer their belief to another disease. Their convictions persist despite negative laboratory results, the benign course of the alleged disease over time, and appropriate reassurances from physicians. Their preoccupation with illness interferes with their interaction with family, friends, and coworkers. They are often addicted to Internet searches about their feared illness, inferring the worst from information (or misinformation) they find there. DIFFERENTIAL DIAGNOSIS Illness anxiety disorder must be differentiated from other medical conditions. Too often these patients are dismissed as “chronic complainers” and careful medical examinations are not performed. Patients with illness anxiety disorder are differentiated from those with somatic symptom disorder by the emphasis in illness anxiety disorder on fear of

having a disease versus the emphasis in somatic symptom disorder on concern about many symptoms; but both may exist to varying degrees in each disorder. Patients with illness anxiety disorder usually complain about fewer symptoms than patients with somatic symptom disorder. Somatic symptom disorder usually has an onset before age 30, whereas illness anxiety disorder has a less specific age of onset. Conversion disorder is acute, generally transient, and usually involves a symptom rather than a particular disease. Pain disorder is chronic, as is hypochondriasis, but the symptoms are limited to complaints of pain. The fear of illness can also occur in patients with depressive and anxiety disorders. If a patient meets the full diagnostic criteria for both illness anxiety disorder and another major mental disorder, such as major depressive disorder or generalized anxiety disorder, the patient should receive both diagnoses. Patients with panic disorder may initially complain that they are affected by a disease (e.g., heart trouble), but careful questioning during the medical history usually uncovers the classic symptoms of a panic attack. Delusional beliefs occur in schizophrenia and other psychotic disorders but can be differentiated from illness anxiety disorder by their delusional intensity and by the presence of other psychotic symptoms. In addition, schizophrenic patients’ somatic delusions tend to be bizarre, idiosyncratic, and out of keeping with their cultural milieus. Illness anxiety disorder can be differentiated from obsessive-compulsive disorder by the singularity of their beliefs and by the absence of compulsive behavioral traits; but there is often an obsessive quality to the patients fear. COURSE AND PROGNOSIS Because the disorder is only recently described, there are no reliable data about the prognosis. One may extrapolate from the course of somatic symptom disorder, which is usually episodic; the episodes last from months to years and are separated by equally long quiescent periods. As with hypochondriasis, a good prognosis is associated with high socioeconomic status, treatment-responsive anxiety or depression, sudden onset of symptoms, the absence of a personality disorder, and the absence of a related nonpsychiatric medical condition. TREATMENT As with somatic symptom disorder, patients with illness anxiety disorder usually resist psychiatric treatment, although some accept this treatment if it takes place in a medical setting and focuses on stress reduction and education in coping with chronic illness. Group psychotherapy may be of help especially if the group is homogeneous with patients suffering from the same disorder. Other forms of psychotherapy, such as individual insight-oriented psychotherapy, behavior therapy, cognitive therapy, and hypnosis, may be useful. The role of frequent, regularly scheduled physical examinations is controversial. Some patients may benefit from being reassured that their complaints are being taken seriously and that they do not have the illness of which they are afraid. Others,