ABSTRACT
BACKGROUND: We aimed to compare patients reporting acute infection with those reporting no infection at onset of chronic fatigue syndrome (CFS). PATIENTS AND METHODS: This study includes 873 patients with CFS referred to a tertiary centre on average 4.8 years after symptom onset. Assessment was by both observer query and self-reports. Antibody analyses against infectious agents including Epstein-Barr virus and enterovirus were performed in a majority of patients. RESULTS: Females comprised 75.3% of the patient group, and the mean age was 33 years. Initial infection was reported by 77%. There was no difference as to antibody analyses. Logistic regression showed that initial infection was independently associated with acute onset of fatigue, improvement of fatigue at referral, and the following symptoms at referral: fever, tender lymph nodes, and myalgia. CONCLUSION: CFS patients with initial infection as a precipitating factor more often report acute onset of fatigue, more frequent accompanying symptoms, and more frequent improvement on referral than do patients without initial infection.
