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We review the concept and importance of functional somatic symptoms and syndromes such as irritable bowel syndrome and chronic fatigue syndrome. On the basis of a literature review, we conclude that a substantial overlap exists between the individual syndromes and that the similarities between them outweigh the differences. Similarities are apparent in case definition, reported symptoms, and in non-symptom association such as patients' sex, outlook, and response to treatment. We conclude that the existing definitions of these syndromes in terms of specific symptoms is of limited value; instead we believe a dimensional classification is likely to be more productive.
Patients seek help from doctors for symptoms and doctors
diagnose diseases to explain them. Symptoms are the
patient’s subjective experience of changes in his or her
body. Diseases are objectively observable abnormalities
i n the body. Difficulties arise when the doctor can find
n o objective changes to explain the patient’s subjective
experience. The symptoms are then referred to as
medically unexplained or functional.1Many different
functional syndromes have been described. In fact, each
medical specialty seems to have at least one: for
rheumatologists, prominent muscle pain and tenderness is
fibromyalgia; for gastroenterologists, abdominal pain with
altered bowel habit is irritable bowel syndrome; and for
infectious-disease specialists, chronic fatigue and myalgia is
a postviral or chronic fatigue syndrome (panel).
We postulate that the existence of specific somatic
syndromes is largely an artefact of medical specialisation.
That is to say that the differentiation of specific functional
syndromes reflects the tendency of specialists to focus on
only those symptoms pertinent to their specialty, rather
than any real differences between patients. To explore
t h i s hypothesis, we reviewed the research literature
w i t h regard to three questions. (1) Do the published
diagnostic criteria for each of the specific functional
syndromes overlap in their constituent symptoms? (2) Do
patients identified as having one functional somatic
syndrome also meet symptom criteria for others? (3)
A r e there similarities across syndromes in the non-
symptom characteristics of sex, coexisting emotional
disorder, proposed aetiology, prognosis, and response to
t r e a t m e n t ?
Various names have been given to medically unexplained
symptoms. These include somatisation, somatoform
disorders, medically unexplained symptoms, and
functional somatic symptoms. In this review, we use the
term functional somatic symptoms.1We define a functional
somatic symptom as one that, after appropriate medical
assessment, cannot be explained in terms of a
conventionally defined medical disease.
936 THELANCET • Vol 354 • September 11, 1999
Lancet 1999; 354: 936–39
Department of Psychological Medicine, Guy’s, King’s and
St Thomas’ School of Medicine, London, UK (Prof S Wessely MD,
C Nimnuan MB BS), and Department of Psychiatry, University of
Edinburgh, Kennedy Tower, Royal Edinburgh Hospital, Edinburgh
EH10 5HF, UK (M Sharpe MRCPsych)
Correspondence to: Dr M Sharpe
Functional somatic symptoms and syndromes pose a
major challenge to medicine. These symptoms are
common, frequently persistent, and are associated with
significant distress, disability, and unnecessary expenditure
of medical resources. In UK primary care, somatic
symptoms and syndromes account for 20% of
c o n s u l t a t i o n s .2Among medical outpatients, somatic
complaints accounted for 25% of new referrals in a Dutch
s t u d y3and for 35% in a UK study.4Even among medical
inpatients, a substantial proportion have complaints that
are found to be functional.5
Functional somatic symptoms are not only common,
they are also clinically important. The prevalence of
emotional distress and disorder in patients who attend
hospital with functional syndromes (such as irritable bowel
syndrome) is higher than in patients with comparable
medical conditions (such as inflammatory bowel disease).6
Furthermore, far from merely representing the “worried
well”, many such patients are severely disabled. For
example, chronic fatigue syndrome is associated with worse
disability than conditions such as heart failure.7
Conventional medical therapy is fairly ineffective for
these patients. The result is frustrated physicians and
disabled and dissatisfied patients with chronic symptoms.
In a follow-up study of patients with non-cardiac chest
pain, Potts and Bass8found that three quarters of patients
had symptoms more than 10 years after presentation.8
T h e resulting costs to patients and to the health system
a r e substantial, especially if patients undergo repeated
investigation and treatment in hospital. Thus, functional
somatic complaints constitute a large, clinically important,
Functional somatic syndromes: one or many ?
S Wessely, C Nimnuan, M Sharpe
We review the concept and importance of functional somatic symptoms and syndromes such as irritable bowel syndrome
and chronic fatigue syndrome. On the basis of a literature review, we conclude that a substantial overlap exists between
the individual syndromes and that the similarities between them outweigh the differences. Similarities are apparent in
case definition, reported symptoms, and in non-symptom association such as patients’ sex, outlook, and response to
treatment. We conclude that the existing definitions of these syndromes in terms of specific symptoms is of limited
value; instead we believe a dimensional classification is likely to be more productive.
Functional somatic syndromes by speciality
Gastroenterology Irritable bowel syndrome, non-ulcer
Gynaecology Premenstrual syndrome, chronic pelvic pain
Rheumatology Fibromyalgia
Cardiology Atypical or non-cardiac chest pain
Respiratory medicine Hyperventilation syndrome
Infectious diseases Chronic (postviral) fatigue syndrome
Neurology Tension headache
Dentistry Temporomandibular joint dysfunction,
atypical facial pain
Ear, nose, and throat Globus syndrome
Allergy Multiple chemical sensitivity
and costly health-care issue that urgently requires better
understanding and improved management. But does the
current classification of such complaints into distinct
functional somatic syndromes aid or hinder this process?
Are there specific functional somatic
s y n d r o m e s ?
Each medical specialty has defined its own syndrome or
syndromes in terms of symptoms that relate to their organ
of interest. In addition, other more controversial
syndromes such as multiple chemical sensitivity and
repetitive strain injury have been proposed but less widely
accepted. Each syndrome tends to be regarded as a unique
diagnostic entity with its own special characteristics.
Furthermore, many of these syndromes are dignified by
their own formal case definition and body of research that
focuses solely on those patients identified as having the
syndrome. We question this orthodoxy and ask whether
these syndromes represent specific diagnostic entities, or
are they rather more like the elephant to the blind man—
simply different parts of a larger animal?
Hypothesis 1: overlap in case definitions of specific
s y n d r o m e s
We compared the case definitions of those functional
syndromes for which a published definition was available.
We found that even the so-called core or diagnostic
features of these syndromes overlap. For example, bloating
or a feeling of abdominal distention is reported in eight of
12 published case definitions for somatic syndromes, and
abdominal pain features in six. Headache is mentioned in
eight and fatigue in six (data available from authors). Our
hypothesis that there is substantial overlap in the case
definitions of specific functional somatic syndromes is
therefore supported by our review of published case
d e f i n i t i o n s .
Hypothesis 2: patients with one functional syndrome
frequently meet diagnostic criteria for other syndromes
Clinicians frequently observe that patients who meet the
criteria for specific functional syndromes report symptoms
other than those included in the case definition. A review
of the clinical research literature confirms this observation.
For example, many studies confirm that if patients who
meet the criteria for irritable bowel syndrome or non-ulcer
dyspepsia are asked about non-alimentary symptoms
(which they are usually not) they report them.
Furthermore, these other symptoms commonly include
ones that define different syndromes. Thus, patients with
irritable bowel syndrome may also have symptoms
indicative of atypical facial pain, chronic fatigue syndrome,
non-cardiac chest pain, food allergy, and chronic
hyperventilation (references available from authors). To
find out the extent to which this overlap occurs with
a l l t h e above syndromes, we carried out a series of cross-
referenced MEDLINE searches to look for papers that
sought to determine whether patients who had received a
diagnosis of one functional somatic syndrome also
r e p o r t e d symptoms of others. We found 13 references
f o r chronic fatigue syndrome that described symptoms
w h i c h overlapped with fibromyalgia, tension headache,
multiple chemical sensitivity, food allergy, premenstrual
syndrome, and irritable bowel syndrome. Conversely,
irritable bowel syndrome was linked with hyperventilation
syndromes, fibromyalgia, chronic fatigue syndrome,
tension headache, aytpical facial pain, non-cardiac chest
pain, chronic pelvic pain, non-ulcer dyspepsia, and
premenstrual syndrome (data available from authors).
These findings lend support to the hypothesis that
p a t i e n t s with one functional syndrome frequently meet
criteria for others.
Hypothesis 3: patients with different functional syndromes
share non-symptom characteristics
S e x—Almost all functional somatic symptoms are more
common in women than in men. In the large US
Epidemiological Catchment Area study,920 of 22 non-
menstrual somatic complaints were more common in
women than in men—the exceptions were chest pain and
difficulties with walking. Other investigations have reported
similar findings, even after the exclusion of gynaecological
d i s o r d e r s .1 0 , 1 1 This predominance of women also applies to
samples of patients selected on the basis of those who met
criteria for specific functional somatic syndromes. Clinical
studies of patients with chronic fatigue syndrome, irritable
bowel syndrome, temporomandibular joint dysfunction,
atypical facial pain, globus syndrome, and tension
headache have all shown that such symptoms predominant
among women. Even in community studies, women
predominate among patients with globus syndrome, irritable
bowel syndrome, chronic fatigue syndrome, non-ulcer
dyspepsia, fibromyalgia, and irritable bowel syndrome.
Emotional disorderThere is a strong association between
the range of functional somatic symptoms and
psychological distress. Russo and Colleagues1 2 showed that
the number of functional complaints was significantly
a n d positively related to the number of current and past
episodes of anxiety and depression. The findings of
c o m m u n i t y1 3 and primary-care studies1 4 , 1 5 also support a
close and linear relation between the number of somatic
symptoms and measures of emotional distress. Most
studies of emotional distress and disorder in patients
w h o attend hospital with a specific functional somatic
syndrome show a substantially increased rate of such
disorders, irrespective of whether the diagnosis is chronic
fatigue syndrome, multiple chemical sensitivity, or irritable
bowel syndrome. We are aware of only a handful o f
exceptions (references available from authors). Patients
who are identified in non-specialist settings as having
functional somatic syndromes are also likely to have an
increased rate of current and lifetime emotional distress
and disorder, but the association is usually weaker.
P h y s i o l o g y —Although there has been limited research into
the physiological mechanisms associated with functional
somatic symptoms, Sharpe and Bass1 6 report findings that
lend support to several identifiable mechanisms. These
findings serve to remind us that such complaints are not to
be regarded as “all in the mind”,1 7 and also suggest further
overlap between these syndromes. In the most general
sense, there is empirical evidence of a link between
functional somatic syndromes and altered functioning of
the central nervous system, which has gradually replaced
suggested abnormalities in specific organ systems. For
example, although muscle dysfunction was originally
suggested as the basis of chronic fatigue syndrome,
fibromyalgia, or both, this explanation has been
l a r g e l y replaced by an appreciation of the role of central
and neuroendocrine mechanisms. Indirect evidence of
abnormalities in serotonergic central-nervous-system
pathways has also been presented for several disorders,
THELANCET • Vol 354 • September 11, 1999 937
including non-nuclear dyspepsia, irritable bowel syndrome,
chronic fatigue syndrome, and premenstrual syndrome
(references available from authors).
History of childhood maltreatment and abuse—C h i l d h o o d
physical, and especially sexual, abuse is more common in
women with functional pelvic pain than in comparison
groups. This association does not seem to be specific,
however, and has also been reported in patients with
irritable bowel syndrome, premenstrual syndrome, tension
headache, fibromyalgia, and chronic fatigue syndrome.
Difficulties in doctor-patient relationship—C o m m o n a l t i e s
can also be observed across functional syndromes in the
interpersonal context, particularly in the doctor-patient
relationship that is frequently unsatisfactory for both
parties. Sharpe and colleagues1 8 reported that patients with
functional somatic symptoms were one of the three most
common types of “difficult to help” patients. Numerous
studies of individual syndromes, such as headache,
non-cardiac chest pain, fibromyalgia, and chronic fatigue
syndrome all reveal that dissatisfaction with medical care is
c o m m o n .
S u m m a r y —The hypothesis that patients with different
functional syndromes also share non-symptom characteristics
is therefore largely supported, although the available data are
inadequate to answer this question definitively.
Hypothesis 4: all functional syndromes respond to the
same therapies
General approaches to management—Numerous guides
for the management of different functional somatic
syndromes provide remarkably similar advice. Although
subjected to only limited systematic evaluation, there are
many themes in common, such as the need to pay
attention to engagement, to explain the physiological
nature of symptoms, to limit investigations, and to
emphasise rehabilitation at the expense of cure.
Antidepressant drug treatment—Although there have been
too few studies to allow definitive statements about the
relative responsiveness of the various functional syndromes
to antidepressants, certain similarities, differences, and
uncertainties can be highlighted. For example, whereas
large well-conducted studies have established the
effectiveness of antidepressant drugs in premenstrual
syndrome, atypical facial pain, and non-cardiac chest pain,
their role in chronic fatigue syndrome and fibromyalgia
i s less clear, particularly with regard to the selective
serotonin-reuptake inhibitors (references available from
authors). The explanation for these differences is unclear
and may simply reflect the small number of trials.
Psychological therapies—Broadly defined psychological
treatment has been advocated for almost all the functional
somatic syndromes and has been shown to be effective in
many. Cognitive behavioural therapy is superior to
minimum care for most of the syndromes in which this
approach has been assessed, such as chronic fatigue
syndrome, premenstrual syndrome, irritable bowel
syndrome, and nearly all the various pain syndromes
(references available from authors).
S u m m a r y —There is a similarity in the treatments
recommended for patients with various functional somatic
syndromes. There is also much evidence of similarity in
response to treatment, although the existing evidence
a l s o points to some differences. For example, low-dose
hydrocortisone therapy is helpful in the management of
chronic fatigue syndrome,1 9 exercise is beneficial in
f i b r o m y a l g i a2 0 and mitral-valve prolapse,2 1 and mebeverine is
of value in irritable bowel syndrome.2 2 However, whether or
not these treatments truly are specific to certain syndromes
(which goes against our hypothesis), or are simply used only
in only specific clinical settings remains unclear. At present,
the hypothesis that all functional syndromes respond to the
same therapies seems to be partly supported.
Implications of the overlap in functional
somatic syndromes
If we accept that the specific functional somatic syndromes
as conventionally defined have much in common, what are
the implications?
C l a s s i f i c a t i o n —The main implication for classification is
that the current practice of regarding patients with
diagnoses of different functional somatic syndromes as
having clinically significant differences is questionable.
Rather, such patients may have similar conditions or
variants of a general functional somatic syndrome. Do we
have a more meaningful way to subclassify patients? Four
approaches may be considered.
The first approach is based on apparent clustering
i n t h e existing case definitions. For example, chronic
fatigue syndrome, fibromyalgia, and irritable bowel might
form one cluster and non-cardiac chest pain and
hyperventilation another (panel).
The second approach is based on epidemiological data.
An empirical approach based on a mathemetical (latent
variable) analysis of the functional somatic symptoms of
primary-care patients in Montreal identified five distinct
factors: irritable bowel syndrome, fibromyalgia, chronic
fatigue syndrome, anxiety, and depression.2 3 H o w e v e r ,
these factors were also highly correlated which suggests
similarities between them.2 4
The third approach is to use one of the existing
psychiatric classifications that subclassify most functional
somatic syndromes into depressive, anxiety, and
somatoform syndromes; the latter category being
f u r t h e r subdivided into somatisation disorder and other
syndromes. This approach has some value in so far as
i t encourages the identification of psychological and
somatic symptoms and the diagnosis of potentially
treatable symptoms. It also allows the identification of
those patients who have longstanding multiple complaints,
so-called somatisation disorder, with a poor prognosis. We
suggest, however, that whatever system is chosen, a
classification based purely on symptoms is of limited value
and offers little clinically useful information about the
p a t i e n t s .
The fourth alternative to the diagnostic suggestions
outlined above is a multiaxial approach.2 5 We suggest such
a scheme may be of greater value to clinicians and
researchers because it provides a fuller description of the
patients and provides useful information for treatment.
The relevant axes should include number of symptoms and
their duration, associated mood disturbance, the
p a t i e n t s ’ attributions for the symptoms, and identifiable
physiological processes.2 5
T r e a t m e n t —Most research on treatment selects patients on
the basis of whether they meet criteria for a specific
functional syndrome. This practice has limited the number
of patients entered into trials and added a spurious
complexity to our understanding of treatment. If we accept
938 THELANCET • Vol 354 • September 11, 1999
that functional somatic syndromes are considered together,
we open the way to more general strategies and services for
their management.
C o n c l u s i o n
Functional somatic symptoms and syndromes are a major
health issue. They are common and may be persistent,
disabling, and costly. Most of the current literature
pertains to specific syndromes defined by medical
subspecialties. We have put forward the hypothesis that the
acceptance of distinct syndromes as defined in the medical
literature should be challenged. We contend that the
patients so defined actually have much in common. A
review of the published evidence largely supports our
suggestion. This hypothesis is open to further testing, and
we are currently attempting to do just that in a study across
medical specialties.
We do not wish to suggest that the care of patients with
functional somatic syndromes should be transferred from
medicine to psychiatry—that would simply be replacing
one monolithic view with another. A more appropriate
position is to call for the return of a “general physician”
with a broad-based approach, perhaps aided by liaison
w i t h psychiatrists or psychologists. We propose an end to
the belief that each “different” syndrome requires its own
particular subspecialist adopting an idiosyncratic approach
in apparent isolation from work elsewhere.
Our thesis is not new. A previous generation of
physicians noted overlaps between what were then
deemed “psychosomatic syndromes”, and also recognised
the alternation or sequence of different syndromes in the
s a m e individual. Among these were Ryle’s multiple visceral
n e u r o s e s ,2 6 Halliday’s concept of psychosomatic
a f f e c t i o n s ,2 7 , 2 8 and Kissen’s theory of syndrome shift.2 9
Unfortunately, none of these general theories were
accompanied by empirical support, and consequently all
have disappeared from our current thinking on the subject.
We argue that their reinstatement is overdue.
A full list of citations for this paper, including the text and tables, is
a v a i l a b l efrom the authors, on request, or on The Lancet’s website
( h t t p : / / w w w . t h e l a n c e t . c o m ) .
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THELANCET • Vol 354 • September 11, 1999 939
... In contrast, patients whose chest pain did not meet PPS criteria most commonly did not meet criteria for any other PPS, and if they did, they rarely met criteria for more than two PPS (10%). These results align with previous studies that show that when the patients' symptoms meet criteria for a specific PPS, they often meet criteria for more than one such condition [51][52][53], which corroborates the clinical importance of multiple PPS. ...
Full-text available
Non-Cardiac Chest Pain (NCCP) is persistent chest pain in the absence of identifiable cardiac pathology. Some NCCP cases meet criteria for Persistent Physical Symptoms (PPS), where the symptoms are both persistent and distressing/disabling. This study aimed to identify patients that might need specialist treatment for PPS by examining cases of NCCP that meet PPS criteria. We analysed data from 285 chest pain patients that had received an NCCP diagnosis after attending an emergency cardiac department. We compared NCCP patients who did and did not meet the additional criteria for heart-related PPS and hypothesised that the groups would differ in terms of psychological variables and workability. We determined that NCCP patients who meet PPS criteria were more likely than other NCCP patients to be inactive or unable to work, reported more general anxiety and anxiety about their health, were more depressed, ruminated more, and, importantly, had a higher number of other PPS. A high proportion of NCCP patients meet PPS criteria, and they are similar to other PPS patients in terms of comorbidity and disability. This highlights the importance of focusing psychological interventions for this subgroup on the interplay between the range of physical and psychological symptoms present.
... Frequently, people with FND also present with functional somatic syndromes (FSSs), such as irritable bowel syndrome (IBS), fibromyalgia/widespread chronic pain (FM/CWP) or chronic fatigue syndrome (CFS) [10]. Despite these being listed as separate conditions in DSM-5, growing voices advocate for overlapping the clinical and aetiological characteristics between FSSs themselves but also with FND [11][12][13][14]. ...
Full-text available
Recent observations suggest that autism spectrum disorder (ASD) co-occurs in people with a functional neurological disorder (FND), but little systematic data are available on the relationship between FND and autism. The study aimed to assess the self-reported autistic traits via a standardized questionnaire and the prevalence of previously diagnosed ASD among people with FND and their 1st-degree relatives. We performed a survey of members of the patient organization FNDHope, using a self-completed questionnaire for screening for autistic traits and ASD: the adult autism subthreshold spectrum (AdAS spectrum). There were 344 respondents diagnosed with FND with a mean age of 39.8 ± 11.6 years (female sex 90%). Eight per cent of respondents volunteered a previous diagnosis of ASD, and 24% reported a 1st-degree relative with a formal diagnosis of ASD, mostly their children. We found that 69% of respondents had scores in the AdAS spectrum indicating a clinically significant ASD and 21% indicating autistic traits. Further studies are needed to provide more evidence regarding the prevalence of ASD in people with FND and how this may influence the aetiology, treatment selection and prognosis.
... "Nociplastic pain" has been used to "identify individuals in whom there is pain and hypersensitivity in regions with apparently normal tissues and without any signs of neuropathy [50], and the term has been applied generally to the fibromyalgia concept. Recent research implicates non-inflammatory antibodies [51], and research about generalized sensory sensitivity links fibromyalgia to other pain disorders and to somatic syndromes [52][53][54]. ...
Objective . Despite data showing that fibromyalgia can be represented as a dimensional disorder, almost all assessments treat fibromyalgia as a dichotomous categorial disorder; and research shows that agreement between community diagnosis of fibromyalgia and fibromyalgia criteria is poor. We investigated the validity of FM as a discrete disorder by exploring the relationships of categorical fibromyalgia, the polysymptomatic distress (PSD) scale, and clinical variables. Methods . In a databank of 33,972 rheumatic disease patients, we studied the categorical diagnosis of fibromyalgia, the PSD scale separately and divided into severity groups, measures of widespread pain, as well as somatic syndrome questionnaires like the Patient Health Questionnaire-15 (PHQ-15), and clinical pain, global, HAQ disability and quality of life scales (EQ-5D). Results . Clinical and demographic variables became more abnormal with increasing PSD score groups, indicating substantial increase in symptoms and pain. The changes across PSD categories were linear and large. When we compared FM- (PSD 8-11) with FM+ (PSD 12-18) patients we found considerable overlap in scores for pain, HAQ disability, patient global, PHQ-15, psychological status, and other variables. Somatic symptom scores were highly correlated with PSD (r=0.718). There was no evidence of a differential pain effect that was present in FM+ but not FM- subjects. Conclusion . Fibromyalgia is more accurately considered a dimensional than a dichotomous disorder. There is vast variability among fibromyalgia positive and negative cases that is governed by the strong and linear relationships between the dimensional PSD scale and clinical variables. The PSD scale provides measurements of the fibromyalgia dimension that support and enlighten categorical fibromyalgia and are an effective tool to measure clinical status and changes. Whatever the mechanism of the pain and symptom increase in fibromyalgia, it appears to operate over the entire fibromyalgia symptom dimension, not just in those with categorical fibromyalgia.
... Although umbrella terms such as medically unexplained (physical) symptoms, functional somatic symptoms, and PSS are used more or less interchangeably, symptoms may also be diagnosed as syndromes, which cluster around bodily symptoms (e.g., chronic low back pain, chronic fatigue syndrome [CFS], or irritable bowel syndrome [IBS]). The diagnostic distinctiveness of these syndromes in the context of PSS is debatable, because patients with syndromes, which use bodily symptoms as diagnostic criteria, often fulfill the diagnostic criteria of more than one syndrome (4,12,13). Although these days most experts accept that there are common overarching factors and syndrome-specific factors (14,15), historically, etiological research focusing on PSS is heterogeneous in nature-that is, often directed at subcategories of PSS (11). ...
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Objective: Up to 10% of the general population experiences persistent somatic symptoms (PSS). Numerous studies in a variety of health domains are dedicated to identifying factors that are associated with PSS onset. The present study aimed to provide an overview of predictors for PSS onset in the general population and the related health domains. Methods: A systematic search was performed identifying longitudinal cohort studies that examined factors associated with PSS onset in the general population. Included studies measured potential predictors before PSS onset and were categorized according to the dynamic biopsychosocial model. Four levels of evidence were discerned for predictors, based on the number of studies and percentage of consistent findings. Results: In the 154 articles eligible for analysis, 27 PSS-subtypes were studied, with primary focus on fibromyalgia (25.0%) and irritable bowel syndrome (23.3%). Of the >250 predictors of PSS onset, 46 were investigated more than once and showed consistent results. Strong evidence identifies biological (e.g., infections, body weight-related metrics), psychological (e.g., sleep problems, psychopathology), interpersonal (life events, childhood/interpersonal stress), contextual (employment), and health behavioral (health care utilization) predictors. Conclusions: The results provide strong evidence for factors from all dynamic biopsychosocial domains, although interpersonal and health behavioral factors are relatively under investigated. Thus, evidence suggests that reduction of predictors of PSS onset to a specific factor/domain may be too restrictive. There is no evidence that this differs per PSS-subtype. Exploring all domains and measuring common factors across subtypes is essential to improve the clinical course of PSS.
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Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating disease that presents with fatigue, sleep disturbances, malaise and cognitive problems. The pathogenesis of ME/CFS is presently unknown and serum levels of potential biomarkers have been inconsistent. Here we show that serum mitochondrial DNA (mtDNA), associated with exosomes, is increased in ME/CFS only after exercise. Moreover, exosomes isolated from patients with ME/CFS stimulate significant release of IL-1β from cultured human microglia. These results provide evidence for a potential novel pathogenetic factor and target for treatment of ME/CFS.
Purpose: To perform a systematic review assessing the relationship between functional somatic syndromes (FSSs) and patient-reported outcome measures (PROMs), post-operative opioid consumption, and hospitalization costs after shoulder and elbow surgery. Methods: A systematic review of the PubMed and Web of Science databases was conducted according to PRISMA guidelines to identify all studies evaluating the effect of having at least 1 FSS (fibromyalgia, irritable bowel syndrome, chronic headaches, chronic low back pain) on outcomes after shoulder and elbow surgeries. Outcomes of interest included postoperative analgesic use, patient reported outcome measures (PROMs), and hospitalization costs. Results: The review identified a total of 320 studies, of which 8 studies met the inclusion criteria. The total number of participants in our 8 included studies was 57,389. Three studies (n=620) reported PROMs. These studies demonstrated that the presence of at least one FSS is predictive of significantly higher pain scores and lower quality of recovery, DASH, ASES, and SANE scores postoperatively. Although scores were inferior in among patients with FSS, two of the three studies showed improvement in PROMs in this group of patients. Seven studies (n= 56,909) reported postoperative opioid use. Of these, 5 reported that a diagnosis of at least one FSS was a strong risk factor for long-term opioid use after surgery. One study (n= 480) found that time-driven activity-based costs were significantly higher in patients with FSSs. Conclusions: Patients with functional somatic syndromes have less favorable PROMs postoperatively, consume more opioids postoperatively, and have higher healthcare costs after elective shoulder and elbow procedures. While PROMs among patients with FSSs are inferior compared to those without FSSs, PROMs still improve compared to baseline. Level of evidence: Level III, systematic review of Level II-III studies.
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The psychosomatic approach to medically unexplained symptoms, myalgic encephalomyelitis and chronic fatigue syndrome (MUS/ME/CFS) is critically reviewed using scientific criteria. Based on the 'Biopsychosocial Model', the psychosomatic theory proposes that patients' dysfunctional beliefs, deconditioning and attentional biases cause or make illness worse, disrupt therapies, and lead to preventable deaths. The evidence reviewed suggests that none of these psychosomatic hypotheses is empirically supported. The lack of robust supportive evidence together with the use of fal-lacious causal assumptions, inappropriate and harmful therapies, broken scientific principles, repeated methodological flaws and an unwillingness to share data all give the appearance of cargo cult science. The psychosomatic approach needs to be replaced by a scientific, biologically grounded approach to MUS/ME/CFS that can be expected to provide patients with appropriate care and treatments. Patients with MUS/ME/CFS and their families have not been treated with the dignity, respect and care that is their human right. Patients with MUS/ME/CFS and their families could consider a class action legal case against the injuring parties.
Background: Persistent physical symptoms (e.g. pain, fatigue) are prevalent in the population and some persons may develop a functional somatic disorder (FSD). We still need to explore the limits between general bodily sensations and FSD, and great controversies exist as regard delimitation, occurrence, risk factors, prognosis, and costs of FSD in the general population. This is mainly due to the lack of focused, sufficient powered, population-based epidemiological studies. Material and Methods: The DanFunD study is the largest focused population-based study on FSD and has the potential to answer these crucial questions regarding the FSD disorders. DanFunD has its origin in the Copenhagen area of Denmark and was initiated in 2009 by an interdisciplinary team of researchers including basic scientists, clinical researchers, epidemiologists, and public health researchers. A population-based cohort of nearly 10,000 people have filled in detailed questionnaires, gone through a thorough health examination, and a biobank is established. The cohort was re-examined after five years. Results:The prevalence of FSD in the Danish population is about 10-15% and is twice as common in women as in men. Persons with FSD report impaired daily activities and low self-perceived health, which qualifies FSD as a major public health problem. The research plan to unravel the risk factors for FSD employs a bio-psycho-social approach according to a detailed plan. Preliminary results are presented, and work is in progress. Likewise, plans for assessing prognosis and health care costs are provided. Conclusion: We invite researchers in the field to collaborate on this unique data material.
The study was performed in 428 patients, of whom 216 were women. The median age was 36.5 (16–75) years and the median weight 67 (42–118) kg. The complaints were registered on a 10-cm-long linear analogue scale by the patients and the physicians. The patients were given coded identical-appearing tablets of placebo and different doses of trimipramine (Surmontil®, Rhône-Poulenc) and randomized into groups A-E. During the 6 weeks of treatment the grades of complaints were reduced to about the half of pretreatment levels. The groups treated with trimipramine (groups A-D) felt significantly more improved than the group receiving placebo (group E). The side effect of tiredness was somewhat more pronounced 1–2 weeks after start with 50 mg trimipramine in the evening than in the groups receiving placebo and lower dose schedules of trimipramine.
One hundred two patients with irritable bowel syndrome were studied in a controlled trial of psychological treatment involving psychotherapy, relaxation, and standard medical treatment compared with standard medical treatment alone. Patients were only selected if their symptoms had not improved with standard medical treatment over the previous 6 months. At 3 months, the treatment group showed significantly greater improvement than the controls on both gastroenterologists' and patients' ratings of diarrhea and abdominal pain, but constipation changed little. Good prognostic factors included overt psychiatric symptoms and intermittent pain exacerbated by stress, whereas those with constant abdominal pain were helped little by this treatment. This study has demonstrated that psychological treatment is feasible and effective in two thirds of those patients with irritable bowel syndrome who do not respond to standard medical treatment.
Background Chronic fatigue syndrome (CFS), fibromyalgia (FM), and multiple chemical sensitivities (MCS) are conditions associated with fatigue and a variety of other symptoms that appear to share many clinical and demographic features. Our objectives were to describe the similarities and differences among patients with CFS, FM, and MCS. Additional objectives were to determine how frequently patients with MCS and FM met the criteria for CFS and if they differed in their health locus of control. Methods Demographic, clinical, and psychosocial measures were prospectively collected in 90 patients, 30 each with CFS, FM, and MCS. Patients were recruited from a university-based referral clinic devoted to the evaluation and treatment of chronic fatigue and three private practices. Variables included demographic features, symptoms characteristic of each condition, psychological complaints, a measure of health locus of control, and information on health care use. Results Overall, the three patient groups were remarkably similar in demographic characteristics and the presence of specific symptoms. Patients with CFS and FM frequently reported symptoms compatible with MCS. Likewise, 70% of patients with FM and 30% of those with MCS met the criteria for CFS. Health care use was substantial among patients with CFS, FM, and MCS, with an average of 22.1, 39.7, and 23.3 visits, respectively, to a medical provider during the prior year. Health locus of control did not differ among the three populations. Conclusions In general, demographic and clinical factors and health locus of control do not clearly distinguish patients with CFS, FM, and MCS. Symptoms typical of each disorder are prevalent in the other two conditions.(Arch Intern Med. 1994;154:2049-2053)
To examine how the type and number of physical symptoms reported by primary care patients are related to psychiatric disorders and functional impairment. Outpatient mental health survey. Four primary care clinics. One thousand adult clinic patients, of whom 631 were selected randomly or consecutively and 369 by convenience. Psychiatric disorders as determined by the Primary Care Evaluation of Mental Disorders procedure; the presence or absence of 15 common physical symptoms and whether symptoms were somatoform (ie, lacked an adequate physical explanation); and functional status as determined by the Medical Outcomes Study Short-form General Health Survey. Each of the 15 common symptoms was frequently somatoform (range, 16% to 33%). The presence of any physical symptom increased the likelihood of a diagnosis of a mood or anxiety disorder by at least twofold to three-fold, and somatoform symptoms had a particularly strong association with psychiatric disorders. The likelihood of a psychiatric disorder increased dramatically with increasing numbers of physical symptoms. The prevalence of a mood disorder in patients with 0 to 1, 2 to 3, 4 to 5, 6 to 8, and 9 or more symptoms was 2%, 12%, 23%, 44%, and 60%, respectively, and the prevalence of an anxiety disorder was 1%, 7%, 13%, 30%, and 48%, respectively. Finally, each physical symptom was associated with significant functional impairment; indeed, the number of physical symptoms was a powerful correlate of functional status. The number of physical symptoms is highly predictive for psychiatric disorders and functional impairment. Multiple or unexplained symptoms may signify a potentially treatable mood or anxiety disorder.
▪A workshop was held 18 to 19 March 1991 at the National Institutes of Health to address critical issues in research concerning the chronic fatigue syndrome (CFS). Case definition, confounding diagnoses, and medical outcome assessment by laboratory and other means were considered from the perspectives of key medical specialties involved in CFS research. It was recommended that published Centers for Disease Control (CDC) case-definition criteria be modified to exclude fewer patients from analysis because of a history of psychiatric disorder. Specific recommendations were made concerning the inclusion or exclusion of other major confounding diagnoses, and a standard panel of laboratory tests was specified for initial patient evaluation. The workshop emphasized the importance of recognizing other conditions that could explain the patient's symptoms and that may be treatable. It was viewed as essential for the investigator to screen for psychiatric disorder using a combination of self-report instruments followed by at least one structured interview to identify patients who should be excluded from studies or considered as a separate subgroup in data analysis. Because CFS is not a homogeneous abnormality and because there is no single pathogenic mechanism, research progress may depend upon delineation of these and other patient subgroups for separate data analysis. Despite preliminary data, no physical finding or laboratory test was deemed confirmatory of the diagnosis of CFS. For assessment of clinical status, investigators must rely on the use of standardized instruments for patient self-reporting of fatigue, mood disturbance, functional status, sleep disorder, global well-being, and pain. Further research is needed to develop better instruments for quantifying these domains in patients with CFS.
Objectives: To summarize the existing data on abuse history and gastrointestinal illness, suggest a conceptual scheme to explain these associations, suggest ways to identify patients at risk, and provide information about mental health referral. Data sources: Review of the pertinent literature by clinicians and investigators at referral centers who are involved in the care of patients with complex gastrointestinal illness and who have experience in the diagnosis and care of patients with abuse history in these settings. Study selection: All research articles and observational data that addressed abuse history in gastroenterologic settings. Articles were identified through a MEDLINE search. Data extraction: Independent extraction by multiple observers. Data synthesis: On the basis of literature review and consensus, it was determined that abuse history is associated with gastrointestinal illness and psychological disturbance; appears more often among women, patients with functional gastrointestinal disorders, and patients seen in referral settings; is not usually known by the physician; and is associated with poorer adjustment to illness and adverse health outcome. Although the mechanisms for this association are unknown, psychological factors (somatization, response bias, reinforcement of abnormal illness behavior) and physiologic factors (psychophysiologic response, enhanced visceral sensitivity) probably contribute. On the basis of these data, recommendations are made on how to identify patients at risk, how to obtain this information, and, if needed, how to make appropriate referrals. Conclusions: The authors agree with existing data on the association between abuse history and gastrointestinal illness. Physicians should ask patients with severe or refractory illness about abuse history. Appropriate referral to a mental health professional may improve the clinical outcome.