Systemic Exertion Intolerance Disease

The diagnostic criteria currently recommended by the Centers for Disease Control is the Institute of Medicine criteria (2015) or sometimes the National Academy of Medicine criteria, as the IOM is now called the NAM. Systemic Exertion Intolerance Disease, or SEID, was the name initially proposed by the committee; however it has not been adopted as a new name for ME/CFS by US organizations; CDC and NIH both refer to the disease as ME/CFS when referring to the IOM critera.

The IOM criteria was first proposed and published by an Institute of Medicine committee on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) in 2015, at the request of the CDC.

Symptoms

Core symptoms

• Decrease in functional capacity with fatigue that lasts six months or longer. People with ME/CFS have fatigue that is very different from just being tired. The fatigue of ME/CFS:
  • Can be severe.
  • Is not a result of unusually difficult activity.
  • Is not relieved by sleep or rest.
  • Was not a problem before becoming ill (not life-long).
• post-exertional malaise (PEM)
• unrefreshing sleep; and

either

• impaired memory or ability to concentrate

or

• orthostatic intolerance (symptoms that occur when standing upright)

Other Common Symptoms

Many people with ME/CFS also have other symptoms, such as:

• Pain not caused by injury: The type of pain, where it occurs, and how severe it is varies. The most common types of pain in ME/CFS are:
  • Muscle pain and aches
  • Joint pain without swelling or redness
  • Headaches, either new or worsening

Some people with ME/CFS may also have:

• Tender lymph nodes in their neck or armpits
• A sore throat that happens often
• Digestive issues, like irritable bowel syndrome
• Chills and night sweats
• Allergies and sensitivities to foods, odors, chemicals, light, or noise
• Muscle weakness
• Shortness of breath
• Irregular heartbeat

Notes

Orthostatic intolerance is also useful for a more severe presentation of the disease; symptom severity and other symptoms are outlined in the Institute of Medicine report.

Adults can be diagnosed at six months of illness and pediatric cases are diagnosed at three months.

Diagnostic criteria for clinicians

Diagnostic Algorithm

Diagnosis requires that the patient have the following three symptoms:

1. A substantial reduction or impairment in the ability to engage in pre-illness levels of occupational, educational, social, or personal activities, that persists for more than 6 months and is accompanied by fatigue, which is often profound, is of new or definite onset (not lifelong), is not the result of ongoing excessive exertion, and is not substantially alleviated by rest, and

2. Post-exertional malaise,* and

3. Unrefreshing sleep*

At least one of the two following manifestations is also required:

1. Cognitive impairment* or

2. Orthostatic intolerance

* Frequency and severity of symptoms should be assessed. The diagnosis of ME/CFS (SEID) should be questioned if patients do not have these symptoms at least half of the time with moderate, substantial, or severe intensity.

Development

In 2014, the U.S. Department of Health and Human Services (HHS), the National Institutes of Health (NIH), the Agency for Healthcare Research and Quality (AHRQ), the Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), and the Social Security Administration (SSA) asked the Institute of Medicine (IOM) to convene an expert committee to examine the evidence base for ME/CFS. In Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness, the committee proposes new diagnostic criteria that will facilitate timely diagnosis and care and enhance understanding among health care providers and the public. These criteria, based on expert analysis and the most up-to-date scientific literature, are streamlined for practical use in the clinical setting. The IOM committee also recommended that the name of the disease be changed—from ME/CFS to systemic exertion intolerance disease (SEID)—to more accurately capture the central characteristics of the illness. However, this name was not adopted by government organizations and not embraced by advocacy organizations.

Authors

The committee on the Diagnostic Criteria for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) consisted of Ellen Wright Clayton, Margarita Alegría, Lucinda Bateman, Lily Chu, Charles Cleeland, Ronald Davis, Betty Diamond, Theodore Ganiats, Betsy Keller, Nancy Klimas, A Martin Lerner, Cynthia Mulrow, Benjamin Natelson, Peter Rowe, and Michael Shelanski.

Criticism

The Institute of Medicine criteria was met with community criticisms, including the following:

• too few symptoms were required; in particular, nervous and immune system symptoms present for CCC and ICC criteria were absent
• unclear descriptions of post-exertional malaise
• absence of pain, which is listed as a "common symptom" but not part of the diagnostic criteria

Twisk (2017) stated that ME and CFS are different illnesses, with ME being a neuromuscular disease and CFS being a partially overlapping fatigue-based illness, and that it was not possible to replace both ME and CFS with a single diagnostic entity. Twisk also stated that SEID included some patients that did not meet either ME or CFS diagnostic criteria.

Clinicians guide

The Report Guide for Clinicians explains the core symptoms, additional symptoms, diagnostic criteria and more.

Centers for Disease Control and Prevention (CDC) website

IOM criteria information has been incorporated into the CDC's ME/CFS website under the tab Information for Healthcare Providers under the "Resources" heading.

The Institute of Medicine report

Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness

Read the report

• Key facts (two pages)
• Report brief (four pages)
• Download full report (282 pages)
• Diagnostic Algorithm Chart
• Proposed Diagnostic Criteria Chart
• Read the full 282 page report online
  • Front matter
  • Summary
  • 1. Introduction
  • 2. Background
  • 3. Current Case Definitions and Diagnostic Criteria, Terminology, and Symptom Constructs and Clusters
  • 4. Review of the Evidence on Major ME/CFS Symptoms and Manifestations
  • 5. Review of the Evidence on Other ME/CFS Symptoms and Manifestations
  • 6. Pediatric ME/CFS
  • 7. Recommendations
  • 8. Dissemination Strategy
  • Public Session Agendas
  • GRADE Grid Template
  • Disability in ME/CFS
  • Questionnaires and Tools That May Be Useful for Assessing ME/CFS Symptoms
  • Biographical Sketches of Committee Members, Consultants, and Staff

• "Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness" Official video presentation

Videos

• Beyond the Data – Chronic Fatigue Syndrome: Advancing Research and Clinical Education

CDC Posted Video - Dr. John Iskander of CDC interviews Dr. Anthony Komaroff (Feb 17, 2016)

• SMCI IOM Briefing in Washington, D.C. Full Coverage

Carol Head of Solve ME/CFS, Dr. Ellen Wright Clayton and Morgan Fairchild

• New Clinical Definitions for ME/CFS - Dr. Lucinda Bateman

Dr. Lucinda Bateman of Bateman Horne Center discusses. (Mar 8, 2015)

Notable studies

• 2015, Chronic Fatigue Syndrome versus Systemic Exertion Intolerance Disease (Full text)
• 2015, Unintended Consequences of not Specifying Exclusionary Illnesses for Systemic Exertion Intolerance Disease (Full text)
• 2016, Replacing Myalgic Encephalomyelitis and Chronic Fatigue Syndrome with Systemic Exercise Intolerance Disease Is Not the Way forward (Full text)
• 2016, Systemic exertion intolerance disease diagnostic criteria applied on an adolescent chronic fatigue syndrome cohort: evaluation of subgroup differences and prognostic utility (Full text)
• 2017, Patients diagnosed with Myalgic encephalomyelitis/chronic fatigue syndrome also fit systemic exertion intolerance disease criteria (Full text)

Letters and commentary

• 2017, An Accurate Diagnosis of Myalgic Encephalomyelitis and Chronic Fatigue Syndrome  requires strict Clinical Case definitions and Objective Test Methods (Full text)
• 2017, Article commentary - Differences of opinion on systemic exercise intolerance disease are not ‘mistakes’: a rejoinder to Jason Sunnquist, Gleason and Fox
• 2017, Article commentary - Mistaken conclusions about systemic exercise intolerance disease being comparable to research case definitions of CFS: A rebuttal to Chu et al.
• 2018, Myalgic Encephalomyelitis, chronic fatigue syndrome, and Systemic Exertion Intolerance Disease: Three distinct clinical entities (Full text)

In popular culture

A February 2016 comic strip referred to SEID and implied it is simply tiredness. See: Blondie comic

See also

• Chronic fatigue syndrome
• ME/CFS
• Myalgic encephalomyelitis

• NIH Post-Infectious ME/CFS Study - SEID will be used in this study.
• Pediatric myalgic encephalomyelitis and chronic fatigue syndrome
• Prognosis for myalgic encephalomyelitis and chronic fatigue syndrome
• Severe and very severe ME

Generally accepted criteria for diagnosing ME/CFS and ME

• Canadian Consensus Criteria (CCC) A diagnosis of moderate and severe forms of ME/CFS are accurately made using this criterion. Adults can be diagnosed at 6 months while pediatric cases are diagnosed at three months.
• International Consensus Criteria (ICC) This criterion will accurately diagnose myalgic encephalomyelitis (ME). There is no requirement that the individual have symptoms for a specified period of time for diagnosis, as opposed to CCC, Fukuda, and SEID, which all require 6 months in adults.
• Systemic Exertion Intolerance Disease (IOM) ME/CFS (IOM) is accurately diagnosed when the core symptoms are met. The Institute of Medicine report as a whole is a comprehensive review of the medical literature available at time of publication (2015). Adults can be diagnosed at 6 months while pediatric cases are diagnosed at three months.

Learn more

• 2015, Chronic fatigue syndrome gets yet another name
• 2015, Systemic Exercise Intolerance Disease: What’s in a name?
• 2018, Diagnosis and Management of Myalgic Encephalomyelitis and Chronic Fatigue Syndrome (Notes the IOM report's diagnostic criteria.)