Last month, research entitled ‘Long-Term Follow-Up of Women with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A 16-Year Longitudinal Study' (Tomić et al 2026) was published on MPDI.
Summary
- Study: Followed 20 women with Myalgic encephalomyelitis/chronic fatigue syndrome over 16 years to assess long-term health outcomes.
- Main findings: 85% developed at least one significant new health condition, including autoimmune disease, cancer, cardiovascular disease, asthma, mental health issues, hypertension, infertility, or a worsening of their ME/CFS.
- Conclusion: The findings suggest that women with ME/CFS may have a substantial long-term physical and mental health needs supporting the requirement for ongoing monitoring and individualised follow-up
Abstract
Background and Objectives: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disorder characterized by persistent or relapsing fatigue lasting at least six months, not alleviated by rest and not previously present. It is accompanied by post-exertional symptom exacerbation and non-restorative sleep. Fatigue is often disabling and reduces daily activity by more than 50%. This study aimed to evaluate the long-term frequency of somatic and psychiatric disorders in women previously diagnosed with ME/CFS and to describe the long-term clinical course, laboratory findings, and fatigue-related changes during a 16-year follow-up period.
Materials and Methods: Sixteen years ago, 40 women diagnosed with ME/CFS according to then-current CDC criteria were enrolled at the Clinic for Infectious Diseases and the Center for Laboratory Medicine, University Clinical Center of Vojvodina. All participants provided informed consent. After 16 years, 20 women agreed to follow-up evaluation. At both time points, participants underwent structured questionnaires, clinical examination, psychological assessment, and comprehensive laboratory testing, including hematological, biochemical, endocrinological, and virological analyses. Fatigue severity was assessed using the FibroFatigue Scale (FFS) and the Multidimensional Assessment of Fatigue (MAF) scale.
Results: During follow-up, 15% of participants were diagnosed with rheumatoid arthritis, 10% with cervical or breast cancer, 5% experienced premature myocardial infarction, 5% developed bronchial asthma, and 20% were diagnosed with clinical depression. Progression of ME/CFS was observed in 15%, while 5% reported infertility. Additionally, 15% developed arterial hypertension. Only 15% of participants did not report symptom worsening or new diagnoses.
Conclusions: Over the 16-year follow-up, 85% of women with ME/CFS developed significant somatic or psychiatric conditions. These findings suggest that women diagnosed with ME/CFS may experience substantial long-term somatic and psychiatric disease burden, supporting the need for continued clinical monitoring and individualized follow-up.
MEA comment
We don't see enough long-term studies in ME-CFS, so this stands out as an exception. But it also points out the need for the best available definition of subjects for results to be meaningful at the end of the extended study duration. Additionally, with smaller cohorts in a long-term study, numbers remaining engaged at follow-up may fall below a useful level.
And there is the risk that definitions used may be to some extent replaced in the interim. The 40 subjects were selected using the CDC criteria (1994), and among the patient measures used, the FibroFatigue Scale used in this study has since been dropped with varying alternatives proposed since, but not clear consensus beyond the more general Widespread Pain Index and Symptom Severity Score instruments.
While these issues are of note for researchers, the study did not produce any clear results, and the discussion over the potential for further study has only lost relevance in the ensuing years.
Ewan Dale, MEA Trustee