Illness Anxiety Disorder

• ALSO KNOWN AS: Hypochondriacal neurosis, hypochondriacal reaction, hypochondria, hypochondriasis
• ANATOMY OR SYSTEM AFFECTED: Psychic-emotional system; all bodily systems
• CAUSES: Psychological disorders
• SYMPTOMS: Excessive worry, endless rumination, and obsessive interpretation of symptoms and sensations; impaired normal activity; chronic persistence despite appropriate medical reassurances and contrary evidence
• DURATION: Chronic, although at times temporary
• TREATMENTS: Psychotherapy, limited drug therapy

DEFINITION: Unwarranted belief about or anxiety over having a serious disease; based on subjective interpretation of physical symptoms or sensations and maintained despite appropriate medical assurances

Causes and Symptoms

With illness anxiety disorder (IAD), formerly called hypochondriasis, the real problem is the patient’s excessive worry and mental preoccupation with having or developing a disease, not the disease about which the patient is so worried. While concern about contracting a serious disease is common and may even make one more prudent, excessive worry, endless rumination, and obsessive interpretation of every symptom and sensation can impair and prevent effective functioning. A diagnosis of IAD is made when the patient’s dread about a disease or diseases impairs normal activity and persists despite appropriate medical reassurances and evidence to the contrary. Some people with IAD can acknowledge that their fears might be without a rational foundation, but the acknowledgment itself fails to bring any relief.

The American Psychiatric Association's 2022 Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, Text Revision (DSM-5-TR) categorizes IAD in the “Somatic Symptom and Related Disorders” chapter. An IAD diagnosis is made when the patient's reoccupation with illness persists for more than six months. The DSM-5-TR lists two subtypes of IAD: care-seeking and care-avoidant IAD. Care-seeking IAD involves the excessive utilization of medical services, and patients with care-avoidant IAD avoid medical intervention because they fear a serious illness will be discovered.

Some research estimates the global lifetime prevalence of IAD at 5.7 percent, though this is a difficult point to calculate. It occurs equally across sexes and can occur at any age, but is most commonly diagnosed in early adulthood. Most clinicians believe that IAD has a primary psychological cause or causes, but that, in general, patients with IAD have only a vague awareness that they are doing something that perpetuates and worsens their IAD symptoms. Patients with IAD do not feign illness; they genuinely believe themselves to be sick or about to become so.

Clinicians usually favor one of four hypotheses about how IAD starts. The hypotheses are based on anecdotal, clinical experience with patients who have gotten better when treated specifically for IAD. Researchers have rarely studied IAD using strict experimental methods. Nevertheless, the anecdotal evidence is important because it gives clinicians a way to think about how to treat the condition.

Early theories asserted that individuals with IAD have a deep-seated anger. Because their life experience is one of disappointment, rejection, and loss, they engage in a two-stage process. Though many believe themselves to be unlovable and unacceptable, they solicit attention and care by presenting themselves as ill. Endless worry and rumination soon render ineffective others’ concern. No amount of reassurance allays their preoccupation and anxiety. In this way, those moved to show concern tire, grow impatient, and finally give up their efforts to help, proving to the worried patient that no one really does care about them after all. Meanwhile, they remain sad and angry. Though this model helps explain some behaviors patients with IAD may exhibit, it is one of many possible explanations.

This view often assumes that IAD is actually a form of defense mechanism that transfers angry, hostile, and critical feelings felt toward others into physical symptoms and signs of disease. Because patients with IAD find it too difficult to admit that they feel angry, isolated, and unloved, they hide from the emotional energy associated with these powerful feelings and transfer them into bodily symptoms. This process appears to occur most frequently when individuals harbor feelings of guilt or reproach due to bereavement and loneliness. In effect, they are angry at being left alone and left uncared for, and they redirect the emotion inwardly as self-reproach manifested in physical complaints.

Others hypothesize that IAD enables those who either believe themselves to be basically bad and unworthy of happiness or feel guilty for being alive (“existential guilt”) to atone for their wrongdoings and, thereby, undo the ever-present guilt that they are always suppressing. The mental anguish makes reparation for the patients’ real, exaggerated, or imagined badness.

A third view is sociologically oriented. Health providers who endorse it see IAD as society’s way of letting people who feel frightened and overwhelmed by life’s challenges escape them, even if temporarily. Individuals with IAD take on a “sick role,” which removes societal expectations that they will face responsibilities. In presenting themselves to the world as too sick to function, they also present themselves as excused from doing so. A schoolchild’s stomachache on the day of a big test provides a relatively common and potentially harmless example of this role at work.

A fourth view utilizes some experimental data that suggest that people with IAD may have lower thresholds for (and lower tolerances of) emotional and physical pain. The data suggest that people with IAD experience physical and/or emotional sensations that are a magnification of what is a normal experience. Thus, a sensation that would be sinus pressure for most people would be experienced as a severe sinus headache for a patient with IAD. Hypersensitivity (lower threshold) to bodily sensations keeps patients with IAD ever on watch for these upsetting, intense sensations because of how amplified the physical and emotional experiences are. What seems to most people an exaggerated concern with symptoms is simply prudent, self-protective vigilance to patients with IAD.

Regardless of why the disorder develops, most patients with IAD go to their physicians with concerns about stomach and intestinal problems or heart and blood circulation problems. These complaints are often part of broader concerns about other potential conditions. The key clinical feature of the condition, however, is not the location or number of bodily complaints but the patients’ belief that they are seriously sick, or are just about to become so. Laboratory tests that reveal healthy organs, physician reassurances that they are well, and long periods in which the dreaded disease fails to manifest itself are not reassuring at all. Patients with IAD seem genuinely unable not to worry.

People with IAD typically present their medical history in great detail and at great length. Often, they have an elaborate, exotic, and complex pathophysiological theory to explain how they acquired the disease and what it is doing, or will soon do, to them. At times, they cite research and give great importance to other causes, tests, or treatments that they and their health providers have not yet tried. Because their actual problem is not, strictly speaking, medical (or not only medical) and because they usually frustrate professional caretakers such as physicians, as well as nonprofessional caretakers such as family and friends, breakdown in the helping process is common. Worried patients tax physicians’ time and resources, while busy physicians feel increasingly drained for what they believe is no good reason. The patients sense that their concerns are not respected or taken seriously; they start to sense resentment. Phone calls to physicians’ offices go unreturned for longer and longer periods. The perceived lack of access to their health providers increases their worry and stress. The physicians increasingly believe that these patients are unappreciative—that they are, in fact, healthy and that they are not cooperating with treatment goals. Instead, patients with IAD are seen as excessively demanding. Anger builds on both sides, relationships deteriorate, and the patient begins to “doctor-shop,” while the physicians lose them as patients.

Although IAD is usually chronic, with periods in which it is more and less severe, temporary hypochondriacal reactions also occur. Such reactions often occur when patients experience a death, serious illness of a loved one, or some other major life stressor, including their own recovery from a life-threatening illness.

When external stressors cause patients' reactions, the hypochondriacal symptoms usually remit when the stressors dissipate or are resolved. The important exception to this rule occurs when family, friends, or health professionals inadvertently reinforce the worry and preoccupation through inappropriate amounts of attention. In effect, they reward hypochondriacal behavior and increase the likelihood that it will persist. A mother may never have received more support and help at home than following breast cancer surgery. A father may never have felt his children’s affection as much as when he recuperated from having a heart attack. An employee may have never obtained special allowances on the job or received so many calls from coworkers as when recovering from herniated disk surgery. A student may never have gotten as special treatment or as many gifts from teammates as when treated for rheumatic fever. What began as a transient hypochondriacal reaction can become chronic IAD.

Depressive disorders often coexist with IAD to the point that even antidepressant medications will simultaneously alleviate IAD symptoms. IAD often accompanies physical illness in older adults. As a group, older adults generally have declining health, experience physical limitations, and are at increased risk for contracting and developing disease. Earlier tendencies toward IAD sometimes intensify with age, with the condition first appearing in old age. IAD is not, however, a typical or expected aspect of normal aging; most older people are not hypochondriacal. In those who are, however, IAD is most likely a symptom of depression, abandonment, or loneliness, which are the conditions that should first be treated.

Treatment and Therapy

The most important aspect of treating IAD is assessing whether a true organic disease exists. Many diseases in their early stages are diffuse and affect multiple organ systems. Neurologic diseases (such as multiple sclerosis), hormonal abnormalities (such as Graves’ disease), and autoimmune/connective tissue diseases (such as systemic lupus) can all manifest themselves in ways that are difficult to diagnose accurately. The frantic and obsessive reporting of patients can just as easily be the worried and detailed reporting of patients with early parathyroid disease; both report symptoms that are multiple, vague, and diffuse. The danger of IAD lies in its being diagnosed in place of true organic disease, which is exactly the kind of event patients with IAD fear will happen.

Of course, there is nothing to prevent someone with true IAD from getting or having a true physical illness. Worrying about illness neither protects from nor prevents illness. Moreover, barring a sudden, lethal accident or event, every patient with IAD is bound to develop organic illness sooner or later. Physical illness can coexist with IAD—and does so when attitudes, symptoms, and mental and emotional states are extreme and disproportionate to the medical problem at hand.

The goal in treating IAD is care, not cure. These patients have an ongoing mental illness or chronic maladaptation and seem to need physical symptoms to justify how they feel. Neither surgical nor medical interventions will ameliorate a psychological need for symptoms. The best treatments when IAD cannot itself be the target of treatment are long-term in orientation and seek to help patients tolerate and accommodate their symptoms while health providers learn to understand and adapt.

Medications have proved useful in treating IAD only when accompanied by pharmacotherapy-sensitive conditions such as major depression or generalized anxiety. When IAD coexists with either mental or physical disease, the latter must be treated in its own right. Secondary IAD means that the primary disorder warrants primary treatment.

The course of IAD is unclear. Clinicians’ anecdotal experience tends to endorse the perception that people with IAD are impossible as patients. Outcome studies, however, belie the pessimism. The research suggests that many who are treated get better, especially if also treated for secondary conditions such as coexisting anxiety or depressive disorder.

A fifty-six-year-old married male, for example, recounted his history as never having been in really good health at any time in his life. He made many physician office visits and had, over the years, seen many physicians, though without ever feeling emotionally connected to them. Over the past several months, he felt increasingly concerned that he was having headaches “all over” his head and that they were caused by an undetected tumor in the middle of his brain, “where no X-ray could detect it.” He had read about magnetic resonance imaging (MRI) in a health letter to which he subscribed and said that he wanted this procedure performed “to catch the tumor early.” Various prescribed medications for his headache usually brought no relief.

While productive at work and promoted several times, he had been passed over for his last promotion because, he believed, his superiors did not like him. He also stated that he believed that many on the job saw him as cynical and pessimistic, but that no one appreciated the “pain and mental anxiety” he endured “day in and day out.”

His spouse of thirty-two years had advanced significantly at a job she had begun ten years earlier, and she seemed to him to be closer to their three children than he was. She was increasingly involved with outside voluntary activities, which kept her quite busy. She reported that she often asked him to join her in at least some of her activities, but he always said no. She said that when she arrived home late, he was often in a state of physical upset for which she could never seem to do the “right thing to help him.” In their joint interview, each admitted often feeling angry at and frustrated with the other. She could never determine why he was sick so often and why her efforts to help only seemed to make his situation worse. He could not understand how she could leave him all alone, feeling as physically bad as he did. He believed that she never seemed to worry that something might happen to him while she was out being “a community do-gooder.” The husband was suffering from a classic case of IAD.

Perspective and Prospects

The term hypochondriasis has ancient origins and reflects a view that all persons are subject to their own humoral ebb and flow. Humors were once thought to be bodily fluids that maintained health, regulated physical functioning, and caused certain personality traits. In classical Greek, hypochondria, the plural of hypochondrion, referred to both a part of the anatomy and the condition formerly known as hypochondriasis. Hypo means “under,” “below,” or “beneath,” and chondrion means literally “cartilage” but in this case refers specifically to the bottom tip of cartilage at the breastbone (the xiphoid or, more formally, xiphisternum). Here, below the breastbone but above the navel, two humors were thought to flow in excess in the person. The liver, producing black bile, made people melancholic, depressed, and depressing; the spleen, producing yellow bile, made people bilious, cross, and cynical. This view, or a variant of it, persisted until the late eighteenth century.

Sigmund Freud and other psychiatrists treated hypochondriacal symptoms with some success while approaching the disorder as a defense mechanism rather than as an excess of bodily fluids. Their treatment for the first time cast a psychological role for what had been seen as a physical problem. Mental health professionals whose theoretical orientation is psychoanalytic or psychodynamic continue to deal with IAD as they deal with other defense mechanisms.

In the 1970s, some researchers began to suggest that IAD was being incorrectly applied to describe a discrete disorder. They argued that IAD is not a true diagnosis. Other researchers disagreed and argued for differentiating between primary and secondary hypochondriasis. Their view has proved to have significant pragmatic utility in treating the wide range of patients who exhibit symptoms of IAD, and it remains the prevailing view.

Given the general unwillingness of patients with IAD to admit that they have a psychological problem and not some yet-to-be-found organic condition, the interpersonal difficulties that often arise between health providers and these patients, and the serious potential of concurrent organic disease, it is not surprising that IAD continues to challenge both persons afflicted with this disorder and those who treat them.

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