Systematic review and meta-analysis of the prevalence of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME)

Abstract

Background: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) has been emerging as a significant health issue worldwide. This study aimed to systemically assess the prevalence of CFS/ME in various aspects of analyses for precise assessment. Methods: We systematically searched prevalence of CFS/ME from public databases from 1980 to December 2018. Data were extracted according to 7 categories for analysis: study participants, gender and age of the participants, case definition, diagnostic method, publication year, and country of the study conducted. Prevalence data were collected and counted individually for studies adopted various case definitions. We analyzed and estimated prevalence rates in various angles: average prevalence, pooled prevalence and meta-analysis of all studies. Results: A total of 1291 articles were initially identified, and 45 articles (46 studies, 56 prevalence data) were selected for this study. Total 1085,976 participants were enrolled from community-based survey (540,901) and primary care sites (545,075). The total average prevalence was 1.40 ± 1.57%, pooled prevalence 0.39%, and meta-analysis 0.68% [95% CI 0.48-0.97]. The prevalence rates were varied by enrolled participants (gender, study participants, and population group), case definitions and diagnostic methods. For example, in the meta-analysis; women (1.36% [95% CI 0.48-0.97]) vs. men (0.86% [95% CI 0.48-0.97]), community-based samples (0.76% [95% CI 0.53-1.10]) vs. primary care sites (0.63% [95% CI 0.37-1.10]), adults ≥ 18 years (0.65% [95% CI 0.43-0.99]) vs. children and adolescents < 18 years (0.55% [95% CI 0.22-1.35]), CDC-1994 (0.89% [95% CI 0.60-1.33]) vs. Holmes (0.17% [95% CI 0.06-0.49]), and interviews (1.14% [95% CI 0.76-1.72]) vs. physician diagnosis (0.09% [95% CI 0.05-0.13]), respectively. Conclusions: This study comprehensively estimated the prevalence of CFS/ME; 0.89% according to the most commonly used case definition CDC-1994, with women approximately 1.5 to 2 folds higher than men in all categories. However, we observed the prevalence rates are widely varied particularly by case definitions and diagnostic methods. An objective diagnostic tool is urgently required for rigorous assessment of the prevalence of CFS/ME.

Changes in DNA methylation profiles of myalgic encephalomyelitis/chronic fatigue syndrome patients reflect systemic dysfunctions

“…Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a poorly understood disease estimated to affect an average of 0.89% [ 1 ] of the global population, though estimates have been higher such as 7%, as has been observed in Iceland [ 2 ]. Core symptoms include severe fatigue, post-exertional malaise, and cognitive, sleep and orthostatic dysfunctions as well as additional debilitating symptoms that collectively are often severe enough to leave patients house or bedbound.…”

Systematic Review of the Epidemiological Burden of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Across Europe: Current Evidence and EUROMENE Research Recommendations for Epidemiology

“…Previous systematic reviews on the prevalence and incidence of ME/CFS included studies from many parts of the world [14][15][16][17][18]. However, most of these reviews were conducted some years ago [14][15][16][17].…”

“…However, most of these reviews were conducted some years ago [14][15][16][17]. In addition, they neither reported the incidence of ME/CFS nor included children or adolescents [14][15][16][17][18]. Also, the reviews were not easily comparable, due to the use of different case definitions for ME/CFS.…”

“…Also, the reviews were not easily comparable, due to the use of different case definitions for ME/CFS. The quality of reporting was not adequately evaluated in most of these reviews, even in the most recent study [18]. Most importantly, none of these previous reviews focused on the epidemiology of ME/CFS in Europe.…”

Review of case definitions for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

“…Furthermore, the application of particular case definitions profoundly impacts epidemiological studies of ME/CFS [14]. The prevalence of ME/CFS could widely vary based on the application of case definitions; for example, there were fivefold differences in prevalence using the Fukuda (0.89%) and the Holmes definition (0.17%) [15].…”