Immune Fitness, Mood, Fatigue, and Quality of Life Prior to SARS-CoV-2 Infection Were Not Identified as Independent Predictors of PASC Fatigue Severity

Post-acute sequelae of SARS-CoV-2 infection (PASC), also referred to as Long COVID, affects millions worldwide and is characterized by persistent fatigue, reduced immune fitness, and mood disturbances. The aim of the current study was to identify if immune fitness, mood, fatigue, and quality of life prior to SARS-CoV-2 infection could predict PASC fatigue severity. A retrospective cross-sectional survey was conducted among 299 Dutch PASC patients. Participants completed validated measures of immune fitness, fatigue (assessed with both the Fatigue Severity Scale and a single-item scale), mood (including stress, anxiety, depression, hostility, loneliness, and happiness) and quality of life for the three months prior to SARS-CoV-2 infection. The same assessments were made for the month before survey completion (i.e., during PASC). Correlational and regression analyses were conducted to identify possible predictors of PASC fatigue severity. Participants were predominantly female (90%): mean age 44.1 (SD 11.2) years. Both assessments of PASC fatigue did not correlate significantly with the prior SARS-CoV-2 assessments of immune fitness, fatigue, mood, and quality of life. The regression analyses revealed no significant predictors for PASC fatigue severity. In conclusion, immune fitness, fatigue, mood and quality of life prior to SARS-CoV-2 infection were not identified as independent predictors of PASC fatigue severity.