Somatizing has been understood from a variety of perspectives, including as a biologic disorder, a cognitive and perceptual process, a form of interpersonal communication, and an unconscious psychological process.

The biologic model of somatization, the newest of the explanatory models, is rooted in a growing body of research suggesting that genetic, neurobiologic, endocrine, and immune system factors can lead to abnormal processing of somatic stimuli. Abnormalities in biomarkers for autonomic, hypothalamic-pituitary-adrenal, and cytokine (particularly IL-1 and IL-6) function have all been associated with somatization. In addition, abnormalities in serotonin levels, related genes, and brain structures involved in the perception of pain and the physiologic state of the body have supported the notion that somatizers may have abnormalities in the central processing of bodily sensations.

In this model, somatization is viewed as a self-validating and self-perpetuating disorder of symptom amplification, an error in nociception, the perception of bodily sensations. Somatizers are unusually sensitive to visceral and bodily sensation and are therefore bothered by normal physiologic sensations and minor discomforts that nonsomatizers ignore, dismiss, or have completely out of their awareness. As these bodily sensations seem so intense, noxious, and disturbing, somatizers with high levels of anxiety, often referred to as hypochondriacs, will readily misattribute them to serious disease.

Once the individual believes himself or herself to be sick, this belief alters subsequent somatic perceptions, and a process of symptom amplification begins. The belief that one is sick makes preexisting symptoms seem more intense because they are now subject to closer scrutiny. The patient’s apparent worsening condition even more firmly convinces the patient that he or she is sick. These patients become hypervigilant for other symptoms that confirm their suspicions and ignore
contradictory information indicating that they are not in fact sick. For example, an individual may notice breathlessness after climbing a flight of stairs and wonder whether this signifies the onset of heart or lung disease. With this suspicion in mind, the patient now thinks that his face looks unusually pale in the mirror when he next shaves. This too seems to provide further evidence of disease progression. Thus, a self-validating and selfperpetuating cycle of cognitive and perceptual amplification has been set in motion.

This model suggests that the patient’s mind and body produce physical symptoms as a way of trying to solve problems in the patient’s life or as a way of protecting the patient from intolerable emotions. This model considers that the symptoms, and their associated behaviors, serve a protective function, but a maladaptive one that can cause its own problems. Some somatizing patients have unconsciously learned that illness behaviors can be used to negotiate stressful circumstances, secure support, and solicit care. The following are some, but by no means all, examples of how physical symptoms and illness behaviors can be produced to serve a protective function.

For some patients, physical symptoms can provide an acceptable problem for which to ask for help. The patient may perceive some insurmountable life problem with which he or she is unable to cope; either because of past experiences or current interpersonal context, he or she is not able to allow the desperation he or she feels into full awareness or to verbalize it to others and ask for help. Instead, the body produces physical symptoms, for which the patient asks to take “time out” and with which he or she shows others “I am in a desperate situation and so I need special care and attention, unusual assistance, and support at this time.”

Other somatizing patients may struggle with feelings of loneliness, and difficulty obtaining loving attention from others, or trouble treating themselves in a forgiving way. Their minds and bodies may produce symptoms to help them gratify yearnings for contact, comfort, and support. Still other patients may have feelings of anger or aggression that they are unable to acknowledge. For these patients, physical symptoms may be an unconscious way of exacting retribution from people in their lives by whom they feel wronged or a way of showing someone in their life that they are not meeting needs.

For patients who struggle with feelings of helplessness around various life problems, physical symptoms, which elicit predictable reactions for others, may be a way of regaining a sense of control. For other patients, physical symptoms may be a way of protecting against underlying feelings of worthlessness. These patients may be able to attribute failures, disappointments, or rejections to a physical incapacity, which can be less painful than focusing on a belief that there is something fundamentally wrong with them. Other patients may be part of a family that functions best when one of its members is ill, and their symptoms optimize the functioning of a challenged family. It is important to emphasize, once again, that these patients are not consciously or intentionally producing their symptoms.

Some degree of health anxiety is normative and adaptive, in that it can motivate one to seek medical attention when a symptom develops. However, when health anxiety becomes persistent and preoccupying, the body’s normal, physiologic “background noise” becomes a nidus for catastrophizing about having a serious disease. This can lead to significant suffering, impaired social and occupational functioning, and overutilization of health care services. Severe health anxiety is classified as “hypochondriasis” when the disease fear persists despite appropriate medical evaluation and reassurance.

Hypochondriacal symptoms shift and fluctuate over time, are often nonspecific and ambiguous, and frequently are similar to the transient benign bodily discomforts experienced by healthy individuals. When interviewed, patients with hypochondriasis talk mainly about their illnesses and medical care and little about family, work, or hobbies. They often seem as concerned with establishing the authenticity of their complaints as with obtaining symptom relief. Some adamantly deny any emotional contribution to their symptoms. This stands in sharp contrast to many patients with serious physical disease who are willing to consider the possibility that anxiety and depression make their symptoms worse. However, other patients with hypochondriasis are aware of their tendency to obsess over symptoms and catastrophize about diseases and are quite distressed by this pattern.

Many patients presenting to primary care settings demonstrate distressing somatic symptoms, and at least a third of symptoms in primary care are medically unexplained. Previously, patients with multiple MUPS were said to have somatization disorder if they met a specific symptom count and distribution. In fact, there is no threshold for the number of MUPS that predicts clinical significance. Rather, the number of MUPS is linearly predictive of degree of functional impairment and of anxiety and depression (indicating the importance of screening for these underlying conditions). Moreover, determining that a somatic symptom is medically unexplained can be problematic. The DSM-5 diagnosis of somatic symptom disorder is made on the basis of positive symptoms (distressing somatic symptoms plus abnormal thoughts, feelings, and behaviors in response to these symptoms), and reserves the requirement for MUPS for the diagnoses of conversion disorder and pseudocyesis. Patients with somatic symptom disorder often have particular difficulty talking about their feelings or connecting the stressors of their lives with their symptoms. For many, difficulties in processing emotions and experiencing their body accurately are related to a history of childhood trauma.

Conversion reactions are sensory or motor dysfunctions suggestive of a neurologic disorder, but are actually expressions of an unconscious psychological need or conflict. The emotional distress is thought of as being “converted” into, or expressed as, physical distress. The process is entirely unconscious, so these patients are not malingering. Symptoms are either sensory or neuromuscular (e.g., weakness, paralysis, ataxia, blindness, aphasia, deafness, anesthesia, paresthesias, or seizures) and usually of short duration. Other features include a prior history of similar symptoms, major emotional stress before onset, and apparent symbolic meaning of the symptom (e.g., paralysis after losing control and striking someone or blindness after viewing a horrifying event). Approximately, half of these patients have a history of childhood abuse or neglect, and over two thirds have an anxiety disorder, such as posttraumatic stress disorder (PTSD). Greater than three quarters of conversion disorder patients have a depressive disorder.

A number of anxiety disorders can produce somatic or healthrelated symptoms. Patients with generalized anxiety are in a chronic state of tension and hyperarousal. They often suffer from multiple somatic manifestations of this constant stress, including restlessness, difficulty concentrating, dry mouth, cold and clammy hands, and gastrointestinal disturbances. Panic anxiety has somatic manifestations that include palpitations, chest pain, tachycardia, dyspnea, choking sensations, diarrhea, sweating, tingling in hands and feet, and fainting. Such signs and symptoms may easily be misinterpreted as evidence of serious illness, such as heart attack. Patients with obsessive-compulsive disorder (OCD) also commonly have fears and obsessions related to germs and disease and typically have a variety of other obsessions and compulsive rituals (e.g., excessive hand washing, checking, counting).

Depression’s neurovegetative symptoms may overshadow the characteristic affective, cognitive, and behavioral changes that are part of the depressive syndrome (see Chapter 227). The chief complaint may be headache, constipation, weakness, fatigue, abdominal pain, insomnia, anorexia, or weight loss. At least one half of somatizing ambulatory medical patients are significantly depressed. These patients worry about and focus attention on their bodies. A positive review of systems, chronic pain, or complaints involving multiple organ systems typify the clinical presentation, and symptoms may recur with the periodicity characteristic of depressions. In most non-Western cultures, somatization is the typical presentation for depression.