Medically unexplained physical symptoms
Encyclopedia
Medically unexplained physical symptoms (MUPS) or medically unexplained symptoms (MUS) are patient symptoms for which the treating physician, other healthcare providers, and research scientists have found no medical cause. The term does not necessarily imply that a physical cause does not exist, but rather notes that cause(s) for given symptoms are uncertain, unknown or disputed—there is no scientific consensus
. A task force of the US National Institutes of Health
states, "Medically unexplained syndromes (MUS) present the most common problems in medicine."
Estimates of primary care consultations with medically unexplained symptoms range from 15% to a high of 66% in specialty settings. Psychiatric co-morbidity is common, but symptoms may not be due exclusively to psychiatric factors and there may be a strong association between psychiatric morbidity and physical symptoms irrespective of whether they have a medical explanation or not. Association with depressive and anxiety disorders increases with the number of unexplained symptoms reported, but medically unexplained symptoms "as a whole" are not necessarily associated with depression and anxiety.
Physical symptoms have been associated with adverse psychosocial and functional outcome across different cultures, irrespective of etiology (either explained or unexplained). One use of the term MUS is in reference to the overlapping symptoms present in a variety of conditions such as chronic fatigue syndrome
, fibromyalgia
, multiple chemical sensitivity
, somatoform disorder
, and Gulf War Illness, which also share a significant overlap in treatment.
or psychosomatic illness
, where the cause or perception of symptoms is mental in origin, or may overlap these terms or be a "lower threshold variant" of them. Because several definitions of both somatization and MUPS exist, and the usage of both terms is inconsistent in medical literature and practice, MUPS is sometimes used interchangeably with somatization
and functional somatic symptoms, although "somatised mental distress" and "somatisation disorders" (based on symptom counts) may not adequately account for most patients seen with MUPS.
A study of terms related to MUPS found that patients often object to the phrase "medically unexplained." The study revealed differences between patients' and doctors' opinions. For example, patients preferred terms using the word "functional" although doctors felt this word was potentially offensive.
When a cause for MUS is found, the symptom(s) are no longer medically unexplained. Some cases of ulcers
and dyspepsia
were considered MUS until bacterial infections were found to be their cause.
in MUPS cases can lead to conflict between patient and health-care provider over the diagnosis and treatment of MUPS. This conflict can occur in the public arena and may involve media controversy, advocacy groups, scientific and political debate and even legal proceedings.
Diagnosis of MUPS is seldom a satisfactory situation for the patient, as many patients feel this implies it is "all in their head." This can lead to an adversarial doctor-patient relationship
, which can develop into an iatrogenic neurosis
, thus complicating the situation. A 2008 review in the British Medical Journal
stated that a doctor must be careful not to tell a patient that nothing is wrong, "as clearly this is not the case." The symptoms that brought the patient to the doctor are real, even when the cause is not known. The doctor should try to explain the symptoms, avoid blaming the patient for them, and work with the patient to develop a symptom management plan.
According to psychiatrist Simon Wessely
, "Various names have been given to medically unexplained symptoms. These include somatisation, somatoform disorders and functional somatic symptoms." He writes that "a substantial overlap exists between the individual syndromes and that the similarities between them outweigh the differences." In reply, the psychiatrist Peter White has stated that "the concept of a general functional somatic syndrome is unhelpful in understanding illness, aetiology, treatment and outcome". In another publication, Wessely states that providing a label for a set of symptoms "is not a neutral act, since specific labels are associated with specific beliefs and attitudes," and "even when organic illness is certain, the illness label can result in adverse behaviour changes.", while there is conflicting evidence on whether such labelling is helpful.
Luxembourg et al write that a substantial portion of MUPS and associated somatoform disorder
s have a clearly-identified cause: repeated psychological traumas, particularly during childhood. Evidence indicates that repeated abuse or other traumas often leads to disturbed lymphatic system
functioning, under-production of cortisol
and overproduction of endogenous opioids, all of which can contribute to MUPS. Those who were seriously traumatized on three or more occasions during childhood were substantially more likely than a control group to develop such difficult-to-treat MUPS as chronic headaches, pelvic pain, and seizures. Trauma researcher Bessel van der Kolk
has noted that chronically abused persons sometimes report a baffling array of MUPS while simultaneously reporting none of the expected psychological distress related to their abuse; he further suggests that, due to severe dissociation
, chronic physical symptoms are these people's only means of expressing what would otherwise be overwhelming emotional pain.
, chronic fatigue syndrome
, irritable bowel syndrome
, unexplained headaches, unexplained back pain
, tinnitus
, and non-cardiac chest pain. As of 2006, CBT had not been tested for menopausal syndrome, chronic facial pain, interstitial cystitis, or chronic pelvic pain.
For antidepressants, both tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) have been tested for some medically unexplained symptoms. TCAs have effects on IBS, fibromyalgia, back pain, headaches, and possibly tinnitus, and single studies show a possible effect in chronic facial pain, non-cardiac chest pain, and interstitial cystitis. SSRIs are usually not effective or have only a weak effect. One exception is menopausal syndrome, where SSRIs are "possibly effective" as well as a third class of antidepressants, the serotonin-norepinephrine reuptake inhibitors (SNRIs).
A randomized controlled trial
of multi-faceted, collaborative care found some improvement in the mental health
of people with forms of MUS involving somatoform disorders and psychological distress.
Scientific consensus
Scientific consensus is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity. Scientific consensus is not by itself a scientific argument, and it is not part of the...
. A task force of the US National Institutes of Health
National Institutes of Health
The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...
states, "Medically unexplained syndromes (MUS) present the most common problems in medicine."
Estimates of primary care consultations with medically unexplained symptoms range from 15% to a high of 66% in specialty settings. Psychiatric co-morbidity is common, but symptoms may not be due exclusively to psychiatric factors and there may be a strong association between psychiatric morbidity and physical symptoms irrespective of whether they have a medical explanation or not. Association with depressive and anxiety disorders increases with the number of unexplained symptoms reported, but medically unexplained symptoms "as a whole" are not necessarily associated with depression and anxiety.
Physical symptoms have been associated with adverse psychosocial and functional outcome across different cultures, irrespective of etiology (either explained or unexplained). One use of the term MUS is in reference to the overlapping symptoms present in a variety of conditions such as chronic fatigue syndrome
Chronic fatigue syndrome
Chronic fatigue syndrome is the most common name used to designate a significantly debilitating medical disorder or group of disorders generally defined by persistent fatigue accompanied by other specific symptoms for a minimum of six months, not due to ongoing exertion, not substantially...
, fibromyalgia
Fibromyalgia
Fibromyalgia is a medical disorder characterized by chronic widespread pain and allodynia, a heightened and painful response to pressure. It is an example of a diagnosis of exclusion...
, multiple chemical sensitivity
Multiple chemical sensitivity
Multiple chemical sensitivity is a chronic medical condition characterized by symptoms the affected person attributes to exposure to low levels of chemicals. Commonly suspected substances include smoke, pesticides, plastics, synthetic fabrics, scented products, petroleum products and paints...
, somatoform disorder
Somatoform disorder
In psychology, a somatoform disorder is a mental disorder characterized by physical symptoms that suggest physical illness or injury - symptoms that cannot be explained fully by a general medical condition, direct effect of a substance, or attributable to another mental disorder . The symptoms that...
, and Gulf War Illness, which also share a significant overlap in treatment.
History and usage
MUPS may be synonymous with somatization disorderSomatization disorder
Somatization disorder is a psychiatric diagnosis applied to patients who persistently complain of varied physical symptoms that have no identifiable physical origin...
or psychosomatic illness
Psychosomatic illness
Psychosomatic medicine is an interdisciplinary medical field studying the relationships of social, psychological, and behavioral factors on bodily processes and well-being in humans and animals...
, where the cause or perception of symptoms is mental in origin, or may overlap these terms or be a "lower threshold variant" of them. Because several definitions of both somatization and MUPS exist, and the usage of both terms is inconsistent in medical literature and practice, MUPS is sometimes used interchangeably with somatization
Somatization
Somatization is currently defined as "a tendency to experience and communicate somatic distress in response to psychosocial stress and to seek medical help for it".This can be, but not always, related to a psychological condition:...
and functional somatic symptoms, although "somatised mental distress" and "somatisation disorders" (based on symptom counts) may not adequately account for most patients seen with MUPS.
A study of terms related to MUPS found that patients often object to the phrase "medically unexplained." The study revealed differences between patients' and doctors' opinions. For example, patients preferred terms using the word "functional" although doctors felt this word was potentially offensive.
When a cause for MUS is found, the symptom(s) are no longer medically unexplained. Some cases of ulcers
Peptic ulcer
A peptic ulcer, also known as PUD or peptic ulcer disease, is the most common ulcer of an area of the gastrointestinal tract that is usually acidic and thus extremely painful. It is defined as mucosal erosions equal to or greater than 0.5 cm...
and dyspepsia
Dyspepsia
Dyspepsia , also known as upset stomach or indigestion, refers to a condition of impaired digestion. It is a medical condition characterized by chronic or recurrent pain in the upper abdomen, upper abdominal fullness and feeling full earlier than expected when eating...
were considered MUS until bacterial infections were found to be their cause.
Contested causation
The lack of known etiologyEtiology
Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....
in MUPS cases can lead to conflict between patient and health-care provider over the diagnosis and treatment of MUPS. This conflict can occur in the public arena and may involve media controversy, advocacy groups, scientific and political debate and even legal proceedings.
Diagnosis of MUPS is seldom a satisfactory situation for the patient, as many patients feel this implies it is "all in their head." This can lead to an adversarial doctor-patient relationship
Doctor-patient relationship
The doctor-patient relationship is central to the practice of healthcare and is essential for the delivery of high-quality health care in the diagnosis and treatment of disease. The doctor-patient relationship forms one of the foundations of contemporary medical ethics...
, which can develop into an iatrogenic neurosis
Neurosis
Neurosis is a class of functional mental disorders involving distress but neither delusions nor hallucinations, whereby behavior is not outside socially acceptable norms. It is also known as psychoneurosis or neurotic disorder, and thus those suffering from it are said to be neurotic...
, thus complicating the situation. A 2008 review in the British Medical Journal
British Medical Journal
BMJ is a partially open-access peer-reviewed medical journal. Originally called the British Medical Journal, the title was officially shortened to BMJ in 1988. The journal is published by the BMJ Group, a wholly owned subsidiary of the British Medical Association...
stated that a doctor must be careful not to tell a patient that nothing is wrong, "as clearly this is not the case." The symptoms that brought the patient to the doctor are real, even when the cause is not known. The doctor should try to explain the symptoms, avoid blaming the patient for them, and work with the patient to develop a symptom management plan.
According to psychiatrist Simon Wessely
Simon Wessely
Simon Wessely is a British psychiatrist. He is professor of epidemiological and liaison psychiatry at the Institute of Psychiatry, King's College London and Head of its department of psychological medicine, Vice Dean for Academic Psychiatry, Teaching and Training at the Institute of Psychiatry, as...
, "Various names have been given to medically unexplained symptoms. These include somatisation, somatoform disorders and functional somatic symptoms." He writes that "a substantial overlap exists between the individual syndromes and that the similarities between them outweigh the differences." In reply, the psychiatrist Peter White has stated that "the concept of a general functional somatic syndrome is unhelpful in understanding illness, aetiology, treatment and outcome". In another publication, Wessely states that providing a label for a set of symptoms "is not a neutral act, since specific labels are associated with specific beliefs and attitudes," and "even when organic illness is certain, the illness label can result in adverse behaviour changes.", while there is conflicting evidence on whether such labelling is helpful.
Luxembourg et al write that a substantial portion of MUPS and associated somatoform disorder
Somatoform disorder
In psychology, a somatoform disorder is a mental disorder characterized by physical symptoms that suggest physical illness or injury - symptoms that cannot be explained fully by a general medical condition, direct effect of a substance, or attributable to another mental disorder . The symptoms that...
s have a clearly-identified cause: repeated psychological traumas, particularly during childhood. Evidence indicates that repeated abuse or other traumas often leads to disturbed lymphatic system
Lymphatic system
The lymphoid system is the part of the immune system comprising a network of conduits called lymphatic vessels that carry a clear fluid called lymph unidirectionally toward the heart. Lymphoid tissue is found in many organs, particularly the lymph nodes, and in the lymphoid follicles associated...
functioning, under-production of cortisol
Cortisol
Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the adrenal gland. It is released in response to stress and a low level of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis; suppress the immune system; and aid in fat,...
and overproduction of endogenous opioids, all of which can contribute to MUPS. Those who were seriously traumatized on three or more occasions during childhood were substantially more likely than a control group to develop such difficult-to-treat MUPS as chronic headaches, pelvic pain, and seizures. Trauma researcher Bessel van der Kolk
Bessel van der Kolk
Bessel van der Kolk has conducted research in the area of post-traumatic stress since the 1970s. His work focuses on the interaction of attachment, neurobiology, and developmental aspects of trauma’s effects on people. He has written the definitive work in the field of psychological trauma,...
has noted that chronically abused persons sometimes report a baffling array of MUPS while simultaneously reporting none of the expected psychological distress related to their abuse; he further suggests that, due to severe dissociation
Dissociation
Dissociation is an altered state of consciousness characterized by partial or complete disruption of the normal integration of a person’s normal conscious or psychological functioning. Dissociation is most commonly experienced as a subjective perception of one's consciousness being detached from...
, chronic physical symptoms are these people's only means of expressing what would otherwise be overwhelming emotional pain.
Treatment
The most effective current treatment for some medically unexplained symptoms is a combination of therapeutic approaches tailored to the individual patient. Most MUS patients are in need of psychotherapy, relaxation therapy and physiotherapy under medical supervision. A Combined therapeutic approach which is at least twice as effective as other therapeutic modalities published to date is described in Steele RE et al. "A novel and effective treatment modality for medically unexplained symptoms" The next best documented approach is cognitive behavioral therapy (CBT), with evidence from multiple randomized controlled trials. Antidepressants may also help, but the evidence is "not yet conclusive." The effectiveness of CBT and antidepressants has not been studied for all medically unexplained symptoms, however. Evidence for a positive effect of CBT has been found in trials for fibromyalgiaFibromyalgia
Fibromyalgia is a medical disorder characterized by chronic widespread pain and allodynia, a heightened and painful response to pressure. It is an example of a diagnosis of exclusion...
, chronic fatigue syndrome
Chronic fatigue syndrome
Chronic fatigue syndrome is the most common name used to designate a significantly debilitating medical disorder or group of disorders generally defined by persistent fatigue accompanied by other specific symptoms for a minimum of six months, not due to ongoing exertion, not substantially...
, irritable bowel syndrome
Irritable bowel syndrome
Irritable bowel syndrome is a diagnosis of exclusion. It is a functional bowel disorder characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits in the absence of any detectable organic cause. In some cases, the symptoms are relieved by bowel movements...
, unexplained headaches, unexplained back pain
Pain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...
, tinnitus
Tinnitus
Tinnitus |ringing]]") is the perception of sound within the human ear in the absence of corresponding external sound.Tinnitus is not a disease, but a symptom that can result from a wide range of underlying causes: abnormally loud sounds in the ear canal for even the briefest period , ear...
, and non-cardiac chest pain. As of 2006, CBT had not been tested for menopausal syndrome, chronic facial pain, interstitial cystitis, or chronic pelvic pain.
For antidepressants, both tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) have been tested for some medically unexplained symptoms. TCAs have effects on IBS, fibromyalgia, back pain, headaches, and possibly tinnitus, and single studies show a possible effect in chronic facial pain, non-cardiac chest pain, and interstitial cystitis. SSRIs are usually not effective or have only a weak effect. One exception is menopausal syndrome, where SSRIs are "possibly effective" as well as a third class of antidepressants, the serotonin-norepinephrine reuptake inhibitors (SNRIs).
A randomized controlled trial
Randomized controlled trial
A randomized controlled trial is a type of scientific experiment - a form of clinical trial - most commonly used in testing the safety and efficacy or effectiveness of healthcare services or health technologies A randomized controlled trial (RCT) is a type of scientific experiment - a form of...
of multi-faceted, collaborative care found some improvement in the mental health
Mental health
Mental health describes either a level of cognitive or emotional well-being or an absence of a mental disorder. From perspectives of the discipline of positive psychology or holism mental health may include an individual's ability to enjoy life and procure a balance between life activities and...
of people with forms of MUS involving somatoform disorders and psychological distress.
External links
- Medically Unexplained Physical Symptoms DHCC/DOD Pamphlet.
- Medically unexplained physical symptoms R. Mayou, British Medical Journal, 1991 September 7: 534–535.