Co-occurrence of memory impairment and fatigue distinguishes post COVID from pandemic-related health effects in the 4-year CON-VINCE cohort study.

A major challenge in diagnosing post COVID lies in differentiating symptoms following a confirmed SARS-CoV-2 infection from those that may also occur in uninfected individuals (post COVID mimics) and be associated with a broader impact of the pandemic. The WHO post COVID definition was applied to the Luxembourgish longitudinal CON-VINCE cohort, where SARS-CoV-2 infection was confirmed via either a positive RT-qPCR or a serology test. Risk factor analysis was conducted on 1,865 individuals. Female gender, lower resilience, greater loneliness, and a higher number of comorbidities were associated with symptoms persistence. The symptomatology and comorbidity profiles of 559 participants (including 50 post COVID and 66 post COVID mimics) were investigated. Two distinct clusters of persistent symptoms were identified: (1) depression with anxiety, present in both infected and non-infected groups, and (2) memory impairment with fatigue, unique to the post COVID group. Therefore, presence of both memory impairment and fatigue may help differentiate post COVID patients from post COVID mimics. Yet, verification that memory impairment was newly developed was not possible, as this symptom was not recorded at baseline. Our findings suggest that future studies should consider factors affecting development of persistent post COVID-like symptoms observed in individuals that were never infected.