Estimation of ME/CFS among individuals with long COVID in an Austrian online support group

Background

Long COVID is frequently characterised by fatigue, cognitive dysfunction and post-exertional malaise (PEM), overlapping with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). International studies suggest that 13–58% of individuals with long COVID may meet ME/CFS criteria, but Austrian data are lacking. This study aimed to provide an exploratory approximation of ME/CFS within a selected Austrian long COVID online population.

Methods

An exploratory cross-sectional online survey was conducted among individuals with self-reported long COVID recruited via an Austrian Facebook support group. ME/CFS status was assessed using items based on the Munich Berlin Symptom Questionnaire (MBSQ) and the DSQ-PEM, operationalised according to the Canadian Consensus Criteria (CCC). Sociodemographic data and functional impairment (Bell Disability Scale) were collected.

Results

Of 361 completed questionnaires, 276 datasets (76.5%) were analysed. Participants were predominantly female (67.0%) with a median age of 45 years (IQR: 38–53); 61.5% were moderately to severely functionally impaired (median Bell score: 60, IQR: 40–70). PEM was reported by 90.0% at least occasionally, and 86.2% described symptom exacerbation after minimal exertion. Pathological fatigue was present in 71.7% at least half of the time. Within this selected sample, 248 participants (89.9%; 95% CI: 85.7–92.9) fulfilled all CCC criteria for ME/CFS. CCC-positive individuals showed lower functional capacity compared to CCC-negative participants (median Bell score: 50 vs. 70).

Conclusions

Findings from this self-selected online sample suggest a high burden of ME/CFS-compatible symptoms in long COVID. Due to selection bias, no population prevalence can be inferred. Further population-based studies are needed.

Key messages

• A high proportion of individuals in a long COVID online support group fulfilled ME/CFS criteria, indicating a substantial symptom burden.

• Long COVID populations may include a substantial subgroup with ME/CFS-like symptom patterns requiring targeted clinical recognition and care.