Objectives: Pandemic circumstances induce the increased prevalence of chronic diseases due to the limitations in accessibility of outpatient treatment and the frequently detected long-term consequences of COVID-19 infection. Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), as one of the proven consequences of COVID-19, is a disease characterised by chronic fatigue not alleviated by rest, and multi-system disorder leading to deterioration in quality of life. The aim of this research is to evaluate the Health-Related Quality of Life (HRQL) of the patients suffered by ME/CFS.

Methods: Patient-reported outcomes (PROs) were collected through the survey performed in Latvia (project No lzp-2019/1-0380). Diagnostics of ME/CFS is complicated and occasionally imprecise, therefore 74 patients with symptomatically similar diagnoses were involved in the survey (ICD-10 code G93.3, R53 and B94.8). Patients were asked to rate their HRQL on a scale from 1 to 100 (100—the best possible HRQL, and 1—the worst) for the year prior to onset of illness, and for the current state. The detailed current level of HRQL was assessed by EuroQol-5D-5L measure (1—the best possible option, and 5—the worst). Descriptive and analytical statistical methods were utilised for analysis of obtained data.

Results: PROs demonstrated the mean HRQL—74.6 (SD 24.0, 95% CI 69.0–80.2) for the year prior to illness and 57.3 (SD 16.3, 95% CI 53.5–61.1) for the current state. The initial relatively low HRQL slightly corelates with the overall HRQL of Latvian population, as Eurostat data discover that only 47.1% of Latvians report good or very good health state (EU average measure is 68.6%). The data of EuroQol-5D-5L of ME/CFS patients were in diapason from 2.9 (self-care) to 3.3 (anxiety/depression).

Conclusion: The results indicate the relatively poor HRQL in ME/CFS, and due to disease progress, coverage predictably will affect a significant ratio of people of working age.