Somatic Symptoms and Related Disorders

Foundations

Somatic symptom and related disorders (SSRD), formerly known as somatoform disorders , are described as the borderland between psychiatry and medicine and are responsible for some of the most challenging and the least understood patient encounters in the emergency department (ED). Individuals who suffer from these disorders must be identified and treated appropriately to avoid patient suffering, inappropriate resource use, and iatrogenic injuries.

Box 99.1 lists the disorders classified in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as SSRD. They include somatic symptom disorder (SSD), illness anxiety disorder (IAD, formerly known as hypochondriasis), conversion disorder, psychological factors affecting medical illness, and factitious disorder (discussed separately in Chapter 100 ). Body dysmorphic disorder (excessive concern for a perceived defect in physical features) is no longer included in this group.

Although prior versions of the DSM emphasized medically unexplained symptoms and their putative psychological causes, current descriptions of these disorders focus on patients’ maladaptive and inappropriate cognitive and affective responses to somatic symptoms rather than the lack of explanation for them. ^, These disorders are thought to be mediated by abnormal sensory perception, processing, interpretation, attribution to pathologic causes, and subsequent hypervigilance toward further sensations.

SSRD are common, with a prevalence of approximately 5% to 7% of the adult population, and are present in many patients with medically unexplained symptoms. ^, The defining features of these disorders, a maladaptive response to bodily sensations, cause patients to seek help for their illness through medical routes rather than psychiatric avenues. However, the SSRD are typically formally diagnosed only via structured psychiatric interview, and these disorders may take many years to diagnose even in longitudinal primary care settings. The disorders are even more challenging to diagnose during a brief ED encounter prioritizing life-threatening illness.

Difficulty identifying the root cause of patients’ distress may cause frustration for both patients and physicians. For example, patients with SSD may have excessive anxiety regarding nonpathologic sensations, whereas patients with IAD may be certain they have a serious medical condition despite contradictory evidence. Thus, after a negative ED work-up, the very nature of the patients’ psychiatric condition may leave them feeling that their concerns have not been adequately addressed, prompting pursuit of extensive, expensive, and invasive medical evaluations. SSRD patients have approximately twice the rate of medical disease seen in the general population. It is unclear whether this is the consequence of more frequent health care use or whether an increased disease burden prompts these patients to have a greater concern for bodily sensations.

Clinicians may also feel frustrated by encounters with patients with SSRD. Frequent ED use by patients with unrealistic expectations and subsequent frustrations may cause physicians to feel these encounters were suboptimal. These patients frequently exhibit an extensive “positive review of symptoms,” which clinicians may feel obligated to evaluate. Even when clinicians suspect SSRD, they are often unwilling to ascribe patient concerns to psychiatric illness at the exclusion of rare but consequential medical diagnoses with nonspecific presentations. However, if the patients’ concerns are recognized and addressed within a patient-centered framework, clinicians may recognize that the “difficult patient” with a “positive review of systems” may have a psychiatric illness requiring further evaluation in an outpatient medical or psychiatric setting.

Clinical Features

Patients with SSRD experience physical symptoms associated with significant distress and impairment that cannot be adequately explained by demonstrable physical pathology despite appropriate medical investigation. These disorders are most common in women of lower socioeconomic status in their 20s and 30s but may be present in any demographic group. Depressive and anxiety disorders are common comorbid conditions, as are nonpsychiatric medical diagnoses.