Risk of chronic fatigue syndrome after COVID-19: A retrospective cohort study of 3227281 patients

Background: Many patients who recovered from COVID-19 still suffer from chronic fatigue syndrome (CFS). It was observed that patients with comorbidities were more prone to developing CFS. This research investigates the risk of post-COVID-19 CFS to assist healthcare professionals in reducing the risk of CFS. Methods: A retrospective cohort study is conducted to investigate the risk of post-COVID-19 CFS based on the TriNetX-sourced electronic health records. Factors including age, sex, race, vaccination, and severity of COVID-19 are analysed. Propensity score matching was applied to balance COVID-19 and non-COVID-19 cohorts. Kaplan-Meier analysis and Cox proportional hazard model were used to perform the relationship between COVID-19 and CFS risk. Results: This research involved 3227281 patients with COVID-19 and 3227281 with non-COVID-19 between 1st January 2020 and 31st December 2023. The incidence of CFS was higher in the COVID-19 group compared to the non-COVID-19 group at 1 follow-up intervals (HR 1.59, 95 % CI = 1.54-1.63). Subgroup analysis revealed increased CFS risk across different age groups (> 18), sexes, races, and comorbid conditions, with notable variations. Conclusions: COVID-19 patients have a higher risk of developing CFS compared to individuals without COVID-19. The increased risk is particularly significant in adults aged 18 years and older. (c) 2024 The Author(s). Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/ 4.0/).