Overview:
Chronic fatigue syndrome (CFS) and myalgic encephalomyelitis (ME) affect approximately 1 million Americans (Jason, Richman, Rademaker, Jordan, Plioplys, Taylor, et al., 199%); while some individuals believe that CFS and ME refer to the same illness, others characterize ME as a more severe, neurological disorder that is discrete from CES (Twisk, 2013). This controversy will be reviewed in detail. The widespread, debilitating symptoms of the illnesses include but are not limited to feeling sick after activity (known as post-exertional malaise), memory and concentration problems, and unrefreshing sleep (IOM, 2015).
Some researchers suggest that ME and CFS were first conceptualized under the diagnostic label ‘newrasthenia,’ defined as a neurological disease characterized by muscle weakness or fatigue. Notably, neurasthenia was one of the most frequently diagnosed illnesses in the late nineteenth century. However, use of this term had substantially decreased by the mid-twentieth century (Wessely, 1994)
Throughout the twentieth century, several outbreaks of idiopathic, fatigue-related illneses occurred, including ‘atypical poliomyelitis’ at Los Angeles County Hospital in 1934 (Meals, Hauser, & Bowe 1938), ‘encephalomyelits’ at the Royal Free Hospital in London in 1955 (Crowley, Nelon, & Stovi 1957), and ‘chronic mononucleosis-like syndrome’ in Lake Tahoe, Nevada, in 1984 (Barnes, 1986). After the Lake Tahoe outbreak, national attention began to focus on this illness (Wessely, 1994), and in 1988, it was named donc fatigue syndrome by the Centers for Disease Control and Prevention (CDC; Holmes, Kaplan, Gantz, Komaroff, Schonberger, Straus, ct al, 1988). For over two decades, the ease definition that the CDC developed (Fukuda, Straus, Hickic, Sharpe, Dobbins, & Komaroff, 1994) has bbeen prominently used in research and clinical practice; however, the Institute of Medicine (10M) recently developed an updated clinical case definition (IOM, 2015).
The annual direct and indirect costs of ME and CFS in the United States are estimated to be between $19 and $24 billion (Jason, Benton, Johnson, & Valentine, 2008). Individuals with ME and CES have an increased risk of cardiovascular-related mortality and a lower mean age of death by suicide and cancer in comparison to the general US population (McManimen, Devendorf, Brow Moore, Moore, & son, 2016).
In addition, arthritis, high blood pressure, fibromyalgia, and multiple chemical sensitivities are commonly comorbid (Jason, Porter, Hunnell, Brown, Rademaker, & Richman, 2011). Although no virus has been identified as the cause of ME and CFS, the immune system may be overactive (Fischer, William, Strauss, Unger, Jason, Marshall, etl, 2014), and there is and fibromyalgia using regression tree analysis and artificial neural network analysis, composed of computer-based models used to evaluate complex correlations. The patients were randomly divided into two groups. One group served to derive classification criteria sets by sophisticated procedures, including artificial neural networks in parallel. These criteria were then validated with the second group. Symptoms that best differentiated patients with ME and CES from the other patients were acute onset of fatigue and sore throat.
Additionally, a recent study highlighted that the duration of post-exertional malaise symptoms can distinguish ME and CFS from other chronic illnesses (Cotler, Holtzman, Dudun, & Jason, 2018). The lesson that is apparent from this section is that it is essential for a consensus on a case definition among investigators for establishing a solid empiric foundation in any illness or disease.
Source: Handbook of Research Methods in Health Psychology, Chapter 17: Chronic Illness, pp 228-241, Date: November 29, 2020 and January 2021 URL: https://books.google.com/books?id=fPQCEAAAQBAJ&pg=PA228 Ref: https://www.routledge.com/Handbook-of-Research-Methods-in-Health-Psychology/Ragin-Keenan/p/book/9780429488320