Neuropsychological consequences three years post-covid-19 are persistent and have great impact on everyday activities.

Abstract

Objective: Post-COVID-19 condition (PCC) is associated with persistent cognitive dysfunction and fatigue, but limited evidence is available regarding long-term outcomes beyond one year.

Design: Longitudinal follow-up assessment.

Patients: Patients who had been previously hospitalized or treated in primary care after COVID-19 infection.

Methods: Cognitive performance (WAIS-III subtests, Rey Complex Figure, RAVLT, and D2 Test of Attention) and fatigue (MFI-20 and MFS) were examined in 82 participants at 18 months post-infection; 59 of these participants were reassessed at 36 months. Activity limitations were evaluated using structured interviews.

Results: At 18 months, the scores on most cognitive tests were significantly below expected premorbid levels (mean differences: 7-17 T-points). At 36 months, deficits persisted in most domains, with only WAIS Matrices and D2 KL showing modest improvement (Cohen's d: ~0.4). Fatigue remained high across all dimensions of MFI-20, and 75-78% of patients exceeding the mental fatigue cut-off of MFS. Self-reported cognitive impact and activity limitations showed minimal change over time.

Conclusions: Post-COVID-19 cognitive dysfunction and fatigue remain prevalent for up to three years post-infection, particularly affecting attention, processing speed, and working memory. These deficits pose substantial barriers to daily functioning and return to work, highlighting the need for targeted rehabilitation strategies.