DSM 5 Somatic Symptom and Related Disorders

The latest edition of DSM 5 has moved away from the need to have no medical explanation in order to make the diagnosis of ‘medically unexplained symptoms’ and gain access to appropriate treatment.  The emphasis now is on symptoms that are substantially more severe than expected in association with distress and impairment.  The diagnosis includes conditions with no medical explanation and conditions where there is some underlying pathology but an exaggerated response. 

‘The major diagnosis in this diagnostic class, Somatic Symptom Disorder, emphasises diagnosis made on the basis of positive symptoms and signs (distressing somatic symptoms plus abnormal thoughts, feelings, and behaviours in response to these symptoms) rather than the absence of a medical explanation for somatic symptoms.  A distinctive characteristic of many individuals with somatic symptom disorders is not the somatic symptoms per se, but instead the way they present and interpret them.’(APA, 2013)

A new category has therefore been created under the heading ‘Somatic Symptom and Related Disorders’.    This includes diagnoses of Somatic Symptom Disorder, Illness Anxiety Disorder, Conversion Disorder, Factitious Disorder, and a variety of other related conditions.  The term ‘Hypochondriasis’ is no longer included.  In two of the conditions the absence of any medical pathophysiology is a criteria for diagnosis; these are Conversion Disorder and Other Specified Somatic Symptom and Related Disorder (which includes Pseudocyesis, a false belief of being pregnant that is associated with objective signs and reported symptoms of pregnancy).

Somatic Symptom Disorder

The diagnostic criteria for Somatic Symptom Disorder noted in DSM 5 are:

  1. One or more somatic symptoms that are distressing or result in significant disruption of daily life.
  2. Excessive thoughts, feelings, or behaviours related to the somatic symptoms or associated health concerns as manifested by at least one of the following:
    1. Disproportionate and persistent thoughts about the seriousness of one’s symptoms.
    2. Persistently high level of anxiety about health or symptoms.
    3. Excessive time and energy devoted to these symptoms or health concerns.
  3. Although any one somatic symptom may not be continuously present, the state of being symptomatic is persistent (typically more than 6 months).

Specify if:

With predominant pain (previously pain disorder): This specifier is for individuals whose somatic symptoms predominantly involve pain.

Specify if:

Persistent: a persistent course is characterized by severe symptoms, marked impairment, and long duration (more than 6 months).

Specify if:

Mild: Only one of the symptoms specified in Criterion B is fulfilled.

Moderate: Two or more of the symptoms specified in Criterion B are fulfilled.

Severe: Two or more of the symptoms specified in Criterion B are fulfilled, plus there are multiple somatic complaints (or one very severe somatic symptom).

The expected prevalence of Somatic Symptom Disorder stated in DSM 5 is higher than that for Somatization Disorder (<1%) but lower than that of Undifferentiated Somatoform Disorder (19%).  Both are more common in women. Nevertheless, the term Somatic Symptom Disorder is considered by DSM 5 to be broadly equivalent to ICD10 F45.1 and ICD9 300.82 Undifferentiated Somatoform Disorder, and includes most patients with Hypochondriasis ICD 10 F45.21 and ICD 9 300.7.

Illness Anxiety Disorder

The diagnostic criteria for Illness Anxiety Disorder noted in DSM 5 are:

  1. Preoccupation with having or acquiring a serious illness.
  2. Somatic symptoms are not present or if present, are only mild in intensity.  If another medical condition is present or there is a high risk for developing a medical condition (e.g., strong family history is present), the preoccupation is clearly excessive or disproportionate.
  3. There is a high level of anxiety about health, and the individual is easily alarmed about personal health status.
  4. The individual performs excessive health-related behaviours (e.g., repeatedly checks his or her body for signs of illness) or exhibits maladaptive avoidance (e.g, avoids doctor appointments and hospitals).
  5. Illness preoccupation has been present for at least 6 months, but the specific illness that is feared may change over that period of time.
  6. The illness-related preoccupation is not better explained by another mental disorder, such as somatic symptom disorder, panic disorder, generalized anxiety disorder, body dysmorphic disorder, obsessive-compulsive disorder, or delusional disorder, somatic type.

Specify whether:

Care-seeking type: Medical care, including physician visits or undergoing tests and procedures, is frequently used.

Care-avoidant type: Medical care is rarely used.

The important distinction between Illness Anxiety Disorder and Somatic Symptom Disorder is that with the former, the individual’s distress emanates not primarily from the physical complaint itself but rather from his or her anxiety about the meaning, significance, or cause of the complaint.  DSM 5 considers the prevalence over 1-2 years to be between 1.3 and 10% of populations, and 6-month to 1 year prevalence to be between 3 and 8%.  Illness Anxiety Disorder encompasses those patients with Hypochondriasis, ICD 10 F45.21, ICD 9 300.7 who do not have somatic symptoms.

Conversion Disorder (Functional Neurological Symptom Disorder)

The diagnostic criteria for Conversion Disorder noted in DSM 5 are:

  1. One or more symptoms of altered voluntary motor or sensory function.
  2. Clinical findings provide evidence of incompatibility between the symptom and recognized neurological or medical conditions.
  3. The symptom or deficit is not better explained by another medical or mental disorder.
  4. The symptom or deficit causes clinically significant distress or impairment in social, occupational, or other important areas of functioning or warrants medical evaluation.

Specify symptom type:

With weakness or paralysis

With abnormal movement

With swallowing symptoms

With speech symptom

With attacks or seizures

With anesthesia or sensory loss

With special sensory symptom

With mixed symptoms

Specify if:

Acute episode: Symptoms present for less than 6 months.

  • : Symptoms occurring for 6 months or more.

Specify if:

With psychological stressor: (specify stressor).

Without psychological stressor.

Terminology can get confusing when clinicians are describing Conversion Disorder.  The concept is often considered so difficult to address with the patient, and much terminology inherently pejorative, that physicians may choose obscure terminology to avoid any appearance of directly challenging the patient.  Some will choose ‘psychogenic’, while others chose the more neutral ‘functional’ (as in abnormal central nervous system function).  The term ‘functional disorder’ is not the same as ‘functional overlay’ which applies to exaggeration of symptoms as seen in Somatic Symptom Disorder and Factitious Disorder.

The diagnosis only includes symptoms of a central neurological disorder when clinical findings demonstrate clear incompatibility with neurological disease.  There are many classical examples where an individual shows and describes obvious disorders, but when observed at other times or when tested in other ways, they are clearly normal (such as weakness or absence of plantar flexion when lying down, but the ability to walk on tip-toes when standing, or an apparent Grand Mal seizure while responding to commands).  The diagnosis does not include disorders such as chronic pain, but Conversion Disorder may co-exist with Somatic Symptom Disorder.  Co-morbidity with anxiety disorders and depressive disorders is common.

Conversion disorder is often associated with dissociative symptoms, and it is often associated with stressful life events and maladaptive personality traits.  It is important to distinguish it from Factitious Disorder and Malingering.  DSM 5 considers the prevalence to be around 5% of referrals to neurology clinics, with an annual incidence in the general population of 2-5/100,000.

Conversion Disorder is classified as ICD 10 F44.4-7 (depending on symptom type), ICD 9 300.11.

Psychological Factors Affecting Other Medical Conditions

The diagnostic criteria for Psychological Factors Affecting Other Medical Conditions noted in DSM 5 are:

  1. A medical symptom or condition (other than a mental disorder) is present.
  2. Psychological or behavioural factors adversely affect the medical condition in one of the following ways:
    1. The factors have influenced the course of the medical condition as shown by a close temporal association between the psychological factors and the development or exacerbation of, or delayed recovery from, the medical condition.
    2. The factors interfere with the treatment of the medical condition (e.g., poor adherence).
    3. The factors constitute additional well-established health risks for the individual.
    4. The factors influence the underlying pathophysiology, precipitating or exacerbating symptoms or necessitating medical attention.
  3. The psychological and behavioural factors in Criterion B are not better explained by another mental disorder (e.g., panic disorder, major depressive disorder, posttraumatic stress disorder).

Specify current severity:

  • : Increases medical risk (e.g., inconsistent adherence with antihypertension treatment).
  • Aggravates underlying medical condition (e.g., anxiety aggravating asthma).
  • : Results in medical hospitalization or emergency room visit.
  • : Results in severe, life-threatening risk (e.g., ignoring heart attack symptoms)

This diagnosis should be reserved for situations in which the effect of the psychological factor on the medical condition is evident, and the psychological factor has clinically significant effects on the course or outcome of the medical condition.  Individuals who develop anxiety as a consequence of a condition should be diagnosed with Adjustment Disorder.  While the prevalence is not clear, DSM 5 notes that it is more common than Somatic Symptom Disorder.  The most frequently seen examples are likely to be avoidance of or poor adherence to treatment because of anxiety, and avoiding investigations when a serious condition is suspected.

Psychological Factors Affecting Other Medical Conditions is classified as ICD 10 F54, ICD 9 316.

Factitious Disorder

The diagnostic criteria for Factitious Disorder noted in DSM 5 are:

Factitious Disorder Imposed on Self

  1. Falsification of physical or psychological signs or symptoms, or induction of injury or disease, associated with identified deception.
  2. The individual presents himself or herself to others as ill, impaired, or injured.
  3. The deceptive behavior is evident even in the absence of obvious external rewards.
  4. The behavior is not better explained by another mental disorder, such as delusional disorder or another psychotic disorder.

Specify:

Single episode

Recurrent episodes (two or more events of falsification of illness and/or induction of injury)

Factitious Disorder Imposed on Another (Previously Factitious Disorder by Proxy)

  1. Falsification of physical or psychological signs or symptoms, or induction of injury or disease, in another, associated with identified deception.
  2. The individual presents another individual (victim) to others as ill, impaired, or injured.
  3. The deceptive behavior is evident even in the absence of obvious external rewards.
  4. The behavior is not better explained by another mental disorder, such as delusional disorder or another psychotic disorder.

Note: The perpetrator, not the victim, receives this diagnosis.

Specify:

Single episode

Recurrent episodes (two or more events of falsification of illness and/or induction of injury)

The essential feature is falsification of medical or psychological signs and symptoms.  The diagnosis requires demonstrating that the individual is taking surreptitious actions to misrepresent, simulate, or cause signs or symptoms of illness or injury in the absence of obvious external rewards.  It includes false reporting of facts such as symptoms, events, and investigation results.  Individuals are at great risk of harm through inappropriate diagnoses and treatments, as well as from induced injury and disease.  The condition is usually one of intermittent episodes.  Persistent unremitting episodes, and single episodes, are less common.  DSM 5 estimates the prevalence of 1% in hospital settings although it is very difficult to achieve an objective measure in a condition where deception is a key criterion.  An important differential diagnosis is malingering, where there is personal gain such as financial gain or time off work.  There needs to be an absence of obvious rewards in order to meet the diagnostic criteria.

Factitious Disorder is classified as ICD 10 F68.10, ICD 9 300.19.

Other Specified Somatic Symptom and Related Disorder

DSM 5 notes that this category applies to presentations in which symptoms characteristic of a somatic symptom and related disorder that cause clinically significant distress or impairment in social, occupational, or other important areas of functioning predominate but do not meet the full criteria for any of the disorders in the somatic symptom and related disorders diagnostic class.  Examples include:

  1. Brief somatic symptom disorder:  Duration of symptoms is less than 6 months.
  2. Brief illness anxiety disorder: Duration of symptoms is less than 6 months.
  3. Illness anxiety disorder without excessive health-related behaviours: Criterion D for illness anxiety disorder is not met.
  4. Pseudocyesis: A false belief of being pregnant that is associated with objective signs and reported symptoms of pregnancy.

These are classified as Other Somatoform Disorders ICD 10 F45.8, ICD 9 300.89.

Unspecified Somatic Symptom and Related Disorder

DSM 5 reserves this category for rare occasions where there are predominantly somatic symptoms but there is insufficient information to make a more specific diagnosis.  These are classified as ICD 10 F45.9 and ICD 9 300.82.

APA 2013. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Arlington, VA, American Psychiatric Association.