Severe fatigue in long COVID - a follow-up study

Abstract

<b>Background:</b> Fatigue is the most reported symptom in patients with persistent complaints of COVID-19 (i.e. long COVID). Longitudinal studies examining the intensity of general fatigue and differentiating between physical and mental fatigue in patients with long COVID are lacking. <b>Methods:</b> Demographics, general fatigue (Checklist Individual Strength - subjective fatigue, CIS-Fatigue; 8-56 points), and physical and mental fatigue (both 3-21 points) were assessed in members of online long COVID support groups at 11 and 24 weeks after onset of COVID-19 related symptoms. A higher score indicates more severe fatigue. A CIS-Fatigue score ≥36 points was used to determine severe (general) fatigue. <b>Results:</b> 239 patients with confirmed COVID-19 participated in this two-wave web-based study (83% women; median [IQR] age: 50 [39-56] years; 60% no self-reported pre-existing comorbidities; 87% good self-reported health before COVID-19; 26% hospitalized during acute infection). The vast majority (85%) of patients had severe fatigue at 11 weeks which decreased to 79% at 24 weeks (<i>P</i>=0.03). Median CIS-Fatigue was 48 [42-53] points at 11 weeks and decreased from 11 to 24 weeks (median change: -2 [-7 to 1] points, <i>P</i>&lt;0.01). At 11 weeks a median physical fatigue of 19 [16-20] and mental fatigue of 15 [10-17] points was reported, which was lower at 24 weeks for physical but not mental fatigue (median change: -1 [-3 to 0], <i>P</i>&lt;0.01; and 0 [-3 to 3] points, <i>P</i>=0.52, respectively). <b>Conclusion:</b> Fatigue in patients with long COVID decreases from 11 to 24 weeks after onset of symptoms. Despite this, severe fatigue remains highly prevalent. Both physical and mental fatigue are present. It remains unclear whether fatigue will resolve on the longer-term.