The prevalence of chronic fatigue syndrome/ myalgic encephalomyelitis: a meta-analysis

Abstract

PurposeTo perform a meta-analysis to examine variability among prevalence estimates for CFS/ME, according to the method of assessment used.MethodsDatabases were systematically searched for studies on CFS/ME prevalence in adults that applied the 1994 Centers for Disease Control (CDC) case definition.1 Estimates were categorized into two methods of assessment: self-reporting of symptoms versus clinical assessment of symptoms. Meta-analysis was performed to pool prevalences by assessment using random effects modeling. This was stratified by sample setting (community or primary care) and heterogeneity was examined using the I2 statistic.ResultsOf 216 records found, 14 studies were considered suitable for inclusion. The pooled prevalence for self-reporting assessment was 3.28% (95% CI: 2.24–4.33) and 0.76% (95% CI: 0.23–1.29) for clinical assessment. High variability was observed among self-reported estimates, while clinically assessed estimates showed greater consistency.ConclusionThe observed heterogeneity in CFS/ME prevalence may be due to differences in method of assessment. Stakeholders should be cautious of prevalence determined by the self-reporting of symptoms alone. The 1994 CDC case definition appeared to be the most reliable clinical assessment tool available at the time of these studies. Improving clinical case definitions and their adoption internationally will enable better comparisons of findings and inform health systems about the true burden of CFS/ME.

Chronic fatigue syndrome (CFS) symptom-based phenotypes in two clinical cohorts of adult patients in the UK and The Netherlands

“…In the UK, adults who attend NHS specialist CFS services have been ill for a median duration of 3 years, and half of those who were employed at the onset of their illness have ceased working (Collin et al, 2011). A meta-analysis of prevalence studies based on clinically-confirmed cases in several countries indicates a prevalence of 0.76% (95% CI 0.23% to 1.29%) (Johnston et al, 2013).…”

Chronic Fatigue Syndrome at Age 16 Years

“…We estimated a ≥3 months' prevalence of 0.90% (95% CI: 0.60 to 1.20), excluding children with depressive symptoms, compared with a pooled prevalence of 0.76% (95% CI: 0.23 to 1.29) for CFS/ME by clinical assessment; and we estimated a prevalence of 2.50% (95% CI: 2.04 to 2.96) by combined parental-and childreport, including children with depressive symptoms, compared with a pooled prevalence of 3.48% (95% CI: 2.36 to 4.60) for self-reported CFS/ME. 44 These comparisons show that selfreported data will overestimate CFS prevalence in children and adults, and they suggest that much of the overreporting can be attributed to depression (which would be excluded in a clinical assessment).…”

Hva er egentlig myalgisk encefalopati?

“…Det er vanskelig å fastslå forekomsten av CFS/ME fordi inklusjonskriteriene i ulike studier har vaert forskjellige (72) . Studier fra USA og England anslår forekomst til 0,2-0,4 % ved bruk av henholdsvis Canada-og Fukudakriteriene (5,73) .…”