Systemic Exertion Intolerance Disease

Systemic Exertion Intolerance Disease (SEID) was the new name proposed at the same time as the diagnostic criteria developed by the National Academy of Medicine (NAM) (formerly the Institute of Medicine, IOM) published on February 10, 2015. The report was titled Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness, and is also referred to as the Institute of Medicine report.

The IOM diagnostic criteria requires chronic fatigue (CF); post-exertional malaise (PEM); unrefreshing sleep; and cognitive impairment and/or orthostatic intolerance (OI). It 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.

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.

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 & 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 recommends 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.

The proposed name and acronym SEID is meant to hone in on key aspects of ME/CFS. Systemic would give credence to the disease being body wide. Exertion Intolerance would key doctors into understanding that the patient CAN NOT tolerate exertion of any kind; physical, cognitive or emotional. (Intolerance is well understood in the medical field in that there is a medical problem. Other diseases, such as gluten intolerance, is a serious medical condition; gluten CAN NOT be consumed.) Disease gave the self-explanatory label of being an organic biological disease.

Diagnostic criteria
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.

Centers for Disease Control and Prevention (CDC) website

 * Note: The name "Systemic Exertion Intolerance Disease" (SEID) has not been adopted but the new diagnostic criteria have been incorporated into the Centers for Disease Control and Prevention (CDC) ME/CFS website under the tab IOM 2015 Diagnostic Criteria.

SEID vs Other criteria
The SEID criteria are the most symptom liberal of the valid disease definition criteria. The Canadian Consensus Criteria (CCC) are for ME/CFS, and International Consensus Criteria (ICC) are for ME.

The IOM report calls for the "retirement" of the Oxford criteria for chronic fatigue syndrome (CFS). The Fukuda criteria are also for CFS.

Comparison chart of the ICC and SEID: ICC compared to IOM (SEID).

Criticism
The main criticisms are:
 * the missing of nervous system symptoms from diagnostic criteria, when ME/CFS is a neurological disease
 * the missing of immune system from diagnostic criteria
 * unclear and broad criterion of the main symptom of post-exertional malaise
 * absence of important symptoms like pain
 * missing exclusions, for example POTS
 * laboratory tests results are missing

ME was the original name for CFS; the names are often used interchangeably or with the acronym ME/CFS. The name SEID, although giving credence to the fact that patients are intolerant to exertion, does not capture the debilitating central nervous system (CNS) symptoms patients experience as the name ME does.

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. (Feb 10, 2015)

Centers for Disease Control and Prevention (CDC) website

 * Note: This clinicians guide has been incorporated into the CDC's ME/CFS website under the tab Information for Healthcare Providers under the "Resources" heading with a page disclaimer: "The findings and conclusions in these documents are those of the author(s) and do not necessarily represent the official position of the Centers for Disease Control and Prevention (CDC)."

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
 * 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

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

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 (SEID) ME/CFS (SEID) 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.)