Introduction: Discrepancies exist regarding the clinical course and prognostic factors for post-COVID fatigue. Therefore, our aim was to assess the timely course of fatigue and its possible predictors in patients previously hospitalised due to SARS-CoV-2 infection.
Material and methods: Patients and employees of the University Hospital in Krakow were assessed with the use of a validated neuropsychological questionnaire. Included were participants aged 18 or more, previously hospitalised due to COVID-19, who completed questionnaires only once > 3 months after the onset of infection. Individuals were retrospectively asked about the presence of eight symptoms of chronic fatigue syndrome at four timepoints: before COVID-19, within 0-4 weeks, 4-12 weeks, and > 12 weeks post-infection.
Results: We enrolled 204 patients [40.2% women, median age 58 (46-66) years] evaluated after a median of 187 (156-220) days from the first positive nasal swab test for SARS-CoV-2. The most common comorbidities were hypertension (44.61%), obesity (36.27%), smoking (28.43%), and hypercholesterolemia (21.08%); none of the patients required mechanical ventilation during hospitalisation. Before COVID-19, 43.62% of patients reported at least one symptom of chronic fatigue. Within 4, 4-12, and > 12 weeks after COVID-19, the prevalence of chronic fatigue was 76.96%, 75.49%, and 66.17%, respectively (all p < 0.001). The frequency of chronic fatigue symptoms decreased within > 12 weeks following the onset of infection but did not return to baseline values, except for self-reported lymph node enlargement. In a multivariable linear regression model, the number of fatigue symptoms was predicted by female sex [β 0.25 (0.12; 0.39), p < 0.001 and 0.26 (0.13; 0.39), p < 0.001 for weeks 0-12 and > 12, respectively], and age [for < 4 weeks, β -0.12 (-0.28; -0.01), p = 0.029].
Conclusions: Most patients previously hospitalised due to COVID-19 suffer from fatigue > 12 weeks after infection onset. The presence of fatigue is predicted by female sex and - only for the acute phase - age.
Keywords: COVID-19; SARS-CoV-2; fatigue; long COVID; middle aged; neurological manifestations; prognosis.