Maybe this paper?
Yes, that's the one - that was an excellent find.
Maybe this paper?
These two studies are cited:Prevalence:
~ 0.4 – 1% 2, 3
• affects all age groups, including children, all racial/ethnic groups, and all socioeconomic strata
• onset most commonly occurs between the ages of 30 and 50
• higher prevalence in females
MYALGIC ENCEPHALOMYELITIS - Adult & Paediatric:
International Consensus Primer for Medical Practitioners
An International Consensus Panel was formed to develop International Consensus Criteria (ICC)1 and a physicians’ primer that includes the ICC, pathophysiology, and diagnostic and treatment protocols for myalgic encephalomyelitis (ME) based on current knowledge and clinical experience.
Goal: to enhance the understanding of ME and promote clarity and consistency in optimal clinical identification and treatment internationally
Target groups: primary care physicians, internists, pain and other health care practitioners, medical students
Myalgic Encephalomyelitis (ME): complex, acquired multi-systemic disease
Pathophysiology: Profound dysfunction/dysregulation of the neurological control system results in faulty communication and interaction between the CNS and major body systems, notably the immune and endocrine systems, dysfunction of cellular energy metabolism and ion transport, and cardiac impairments.
Cardinal symptom: a pathological low threshold of fatigability that is characterized by an inability to produce sufficient energy on demand. There are measurable, objective, adverse responses to normal exertion, resulting in exhaustion, extreme weakness, exacerbation of symptoms, and a prolonged recovery period.
Note: Myalgic encephalomyelitis (ME) is the name recommended for those meeting the ICC.
Classification: Myalgic encephalomyelitis has been classified as a neurological disease by the WHO since 1969. WHO stipulates that the same condition cannot be classified to more than one rubric because, by definition, individual categories and subcategories must remain mutually exclusive. Thus, it is essential that patients meeting the ICC for ME are removed from overly inclusive groups.
Myalgic encephalomyelitis:
neurological disease
WHO ICD G93.3
Epidemiology
Prevalence:
~ 0.4 – 1% 2, 3
• affects all age groups, including children, all racial/ethnic groups, and all socioeconomic strata
• onset most commonly occurs between the ages of 30 and 50
• higher prevalence in females
ME:
• generally sporadic
• endemic
• widely dispersed epidemics
Prognosis
• Currently there is no known cure.
• Early intervention and appropriate treatment strategies may lessen severity of symptoms.
• Restoration to full pre-morbid health and function is rare.4
• Prognosis for an individual cannot be predicted with certainty.
Paediatric: Children can be very severely afflicted.
• Children with less severe symptoms are more likely to go into remission than adults.
Etiology
Predisposing Factors: multifactorial and fairly individual
1. Genetic predisposition: increased susceptibility associated with
Environmental factors may outweigh genetic predisposition.15 Several epidemics support an infectious cause.16
- Gene expression modifications: neurological, hematological, metabolic, sensory, immunological disease, function/response, infection, inflammation, cardiovascular, cancer, cell death and endocrine5-12
- Clusters of combined gene data suggest distinct genomic subtypes and disease associations.12,13
- Familial and twin studies indicate there is a higher degree of ME in relatives, to third generation.14
2. Pre-onset environmental events that may compromise the neurological and immune systems, and increase susceptibility to infection: • minor infections
• immunization • exposure to new infectious agents, especially when traveling or following recent infections • contaminated water • recycled air in flights • blood transfusions • anaesthetics • toxic chemicals • heavy metals • severe physical trauma: whiplash/spinal injury/surgery • undue psychological stress17-23
Precipitating Events and Causal Factors: Most patients enjoyed healthy, active lifestyles prior to the onset of ME. Widely dispersed epidemics support an infectious cause. Symptoms at onset are usually consistent with an infectious process.
Onset Survey
1,000+ patients
75.6%: infection alone or
infection + 1 or more factors:
environmental exposure, physical
trauma, vaccinations, other stressors
Vernon SD. CFIDS of America
1. Infectious agents associated with ME
Viruses: • Enterovirus24-26 • Epstein Barr virus (EBV)27 • Human herpes virus (HHV 6 and 7)28, 29 • Cytomegalovirus30 • Parvovirus B1931
Bacteria: Chlamydophila pneumonia32 • Mycoplasma33 • Coxiella burnettii27
It is unclear whether these infectious agents initiated ME or are opportunistic and developed due to an impaired immune system. No one virus has been universally implicated for all patients. A prospective study reported that six months following acute infections of Epstein-Barr virus, Coxiella Burnetii, or Ross River virus, 11% of the patients had CFS.34 This supports the presence of ME subtypes. Antibody testing for a number of viruses revealed subtype-specific relationships for Epstein Barr virus and enterovirus, two of the most common infectious triggers for ME.27
2. Possible etiological process: A growing body of evidence suggests that a primary cause of ME is neuropathic viruses that may infect neurological and immune cells and damage the capillaries and micro-arteries in the CNS bed causing diffuse brain injury. The initial infection may cause profound dysregulation of immune system pathways that may become chronic or cause autoimmunity even when the level of the infectious agent is reduced.35
ME Phases
1. Infectious Onset/Acute Phase < 6 months: Most patients have a distinct acute onset where flu-like or upper respiratory symptoms or other signs of an infectious process are evident. The incubation period usually runs a few days to a week. Instead of recovering, the patient’s condition worsens, and the symptoms that identify the distinctive character of ME begin to appear as a cluster. Approximately 20% of patients have a gradual onset that may follow events that compromise the immune system, making them vulnerable to new or reactivation of persistent latent infections that can further overwhelm the immune system.26
2. Chronic Phase > 6 months: Generally, symptoms tend to be more stable in the chronic phase. Some patients have some improvement in the chronic phase while others have a progressive decline in health.
I read a comment on Jennie Spotila's blog that ME/CFS is 236th on NIH’s grant list out of 247 ailments, in terms of funds allocated.
Does anyone know the source of this?
It probably comes from here:
http://report.nih.gov/categorical_spending.aspx
By clicking on the year (top row), the funding sorts by decreasing amounts.
Thanks Ember.The ICC contains a statement on prevalence.
...
These two studies are cited:
2. Jason LA, Richman JA, et al. A community-based study of Chronic Fatigue Syndr ome. Arch Int Med 1999; 159:2129-2137. [PMID: 10527290]
3. Lorusso L, Mikhaylova SV, et al. Immunological aspects of chronic fatigue syndrome. Autoimmun Rev2009; 8: 287-91. [PMID: 18801465]
Findings indicated that CFS occurs in about 0.42% (95% confidence interval, 0.29%-0.56%) of this random community-based sample.
The estimated worldwide prevalence of CFS is 0.4–1% and it affects over 800,000 people in the United States and approximately 240,000 patients in the UK.
The estimated worldwide prevalence of CFS is 0.4–1% and it affects over 800,000 people in the United States and approximately 240,000 patients in the UK [4,10].
Thanks Denise,Is it worth looking at the references in this article re prevalence?
http://www.biomedcentral.com/1741-7015/9/91
Thanks Denise,
That's a UK study, and it estimates prevalence rates to be at 0.2% (compared to Jason's estimate of 0.42%) for "any of the study case definitions."
Depending on the criteria used, its estimates range from 0.11% to 0.2%, and even as low as 0.03% using the authors' own epidemiological case definition (ECD):
"The estimated minimum prevalence rate of ME/CFS was 0.2% for cases meeting any of the study case definitions, 0.19% for the CDC-1994 definition, 0.11% for the Canadian definition and 0.03% for the ECD."
So it's a UK-based study, and its estimates are much lower than Jason's. I'm not sure how helpful it is for our case, esp with an estimate as low as 0.03% using their own criteria.
If you mean references that are useful for prevalence rates, then I don't think there are. It uses data from English primary care clinics rather than data from other research papers.Sorry - I was not clear - are there any references that are useful?
If you mean references that are useful for prevalence rates, then I don't think there are. It uses data from English primary care clinics rather than data from other research papers.
Does anyone remember which study/researcher (Price? Prince??) claimed to use patients diagnosed according to Fukuda, but in reality, they did something like accept patients with chronic fatigue minus the other Fukuda requirements? I thought this might be in line with Bob's comment above and that the phrase "equivalent to Oxford" was really important.Hi Sasha, I can delete this post after you've considered it. Oxford are a broad/inclusive set of criteria that simply diagnoses "chronic fatigue" (no other symptoms required.) Would you also be able to include a comment about removing research evidence that was based on a general 'chronic fatigue' recruitment criteria (i.e. equivalent to Oxford) whether Oxford was used or not? I think a lot of CBT/GET research might be based on recruitment criteria that simply required chronic fatigue for a period of time. They don't all use Oxford.
Patients were eligible for the study if they met the US Centers for Disease Control and Prevention criteria for CFS,1 with the exception of the criterion requiring four of eight additional symptoms to be present. Severe fatigue and severe functional impairment were defined by cut-off scores—a score of 40 or more on the subscale fatigue severity of the checklist individual strength and a score of 800 or more on the sickness impact profile. Additional inclusion criteria for this study were age between 18 and 60 years and residence within 1·5 h travelling time of one of the study centres. Additional exclusion criteria were previous or current participation in CFS research, pregnancy, and current treatment to achieve pregnancy.
I don't plan to comment on the Draft Report. The US government's determination to ignore expert opinion is too galling for that. Dr. Unger has spent the past few years gathering data on ME/CFS patients through her multi-site study. She told the Panel that we need improved patient outcome measures specific to ME/CFS; but to develop questionnaires that will better capture patients' experience, we first need focus groups to identify the most important illness factors.I feel that this is an opportunity to voice our opposition. If we don't do it now, will we be stuck for another 30 years with this?
In addition, we were told at the start that the three efforts; IOM, P2P and CDC study will work in synergy. Does that mean that the resulting p2p report will have an effect on the IOM one?
The other thing to keep in mind is; in what way will this report advance the science for the disease?
The Draft Report calls for protest.Since the expert ME/CFS scientific and medical community has developed and adopted a case definition for research and clinical purposes, this effort is unnecessary and would waste scarce taxpayer funds that would be much better directed toward funding research on this disease. Worse, this effort threatens to move ME/CFS science backward by engaging non-experts in the development of a case definition for a complex disease about which they are not knowledgeable.
I have decided, personally, not to formally comment on the P2P draft report. I am joining other patients and advocates in continuing to protest the whole process of P2P for ME/CFS.
I feel that this process should never have been chosen for this "controversial" topic. The parameters set upon it by the NIH were meant to assure an unsound, inferior result.