Incidence age is bimodal for myalgic encephalomyelitis/chronic fatigue syndrome, with higher severity burden for early onset disease
Open Access
- 21 January 2026
- journal article
- Published by Oxford University Press (OUP) in Oxford Open Immunology
- Vol. 7 (1)
Abstract
Myalgic Encephalomyelitis, or Chronic Fatigue Syndrome (ME/CFS), is a disease of uncertain origin. Studies of Norwegian health records have suggested that ME/CFS incidence across age groups is bimodal—a characteristic that could provide insight into the aetiology of the disease. Here, we analysed survey data from over 9000 respondents with ME/CFS from 10 European countries, and observe an early onset peak with a mean of 16.0 years old (standard deviation [SD]: 4.3) and a late onset peak at 36.6 years old (SD: 10.5). Statistical support for multimodal onset age was evident in 7 of the 10 countries examined. Infection as a trigger for ME/CFS was 10 percentage points higher among early compared to late onset disease (p = 2.1 × 10−13). Early onset ME/CFS was associated with greater odds of being severely or very severely affected (OR = 2.15, 95% CI [1.84–2.51], p < 2 × 10−16). Those with first degree relatives with ME/CFS had greater odds of early than late onset ME/CFS (OR = 1.43, 95% CI [1.25–1.63], p = 4.4 × 10−07). We further validated our findings in a UK dataset where we replicated bimodal onset age and observed significantly greater odds of glandular fever/infectious mononucleosis as a trigger in early onset cases (OR = 2.32, 95% CI [1.99–2.71], p = 2.4 × 10−24). Our findings suggest that incidence of ME/CFS peaks in adolescence and in early middle-age and that early onset ME/CFS is more common in those with affected relatives, more often triggered by infection, and associated with more severe disease.Keywords
Funding Information
- Clare Francis Research Fellowship funded by Action
This publication has 47 references indexed in Scilit:
- Incidence and Prevalence of Post-COVID-19 Myalgic Encephalomyelitis: A Report from the Observational RECOVER-Adult StudyJournal of General Internal Medicine, 2025
- The persistence of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) after SARS-CoV-2 infection: A systematic review and meta-analysisJournal of Infection, 2024
- The Prevalence of Pediatric Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in a Community-Based SampleChild & Youth Care Forum, 2020
- Incidence rates of Guillain Barré (GBS), chronic fatigue/systemic exertion intolerance disease (CFS/SEID) and postural orthostatic tachycardia syndrome (POTS) prior to introduction of human papilloma virus (HPV) vaccination among adolescent girls in Finland, 2002–2012Papillomavirus Research, 2017
- Genetic susceptibility has a more important role in pediatric-onset Crohnʼs disease than in adult-onset Crohnʼs diseaseInflammatory Bowel Diseases, 2007
- An Introduction to Categorical Data Analysis2006
- Specificities of inflammatory bowel disease in childhoodBest Practice & Research Clinical Gastroenterology, 2004
- Vitiligo: complex segregation and linkage disequilibrium analyses with respect to microsatellite loci spanning the HLAHuman Genetics, 2002
- A Community-Based Study of Chronic Fatigue SyndromeArchives of internal medicine (1960), 1999
- Recall bias in epidemiologic studiesJournal of Clinical Epidemiology, 1990