1 Department of Psychology, Concordia University, Montreal, Canada.
2 Faculty of Health Sciences, Universitat Oberta de Catalunya, Barcelona, Spain.
3 Neuropsychology Unit, Neurology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
4 Facultat de Psicologia, Ciències de l'Educació i l'Esport, Blanquerna, Universitat Ramon Llull, Barcelona, Spain.
5 Internal Medicine Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
6 Neurodiagnostic Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
7 Neurology Department, Headache Unit, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
8 Infectious Disease Unit, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.

Cognitive difficulties are reported as lasting sequelae within post COVID-19 condition. However, the chronicity of these difficulties and related factors of fatigue, mood, and perceived health have yet to be fully determined. To address this, the current longitudinal study aimed to clarify the trends of cognitive test performance and cognitive domain impairment following COVID-19 onset, and whether hospitalization influences outcomes. 57 participants who reported subjective cognitive difficulties after confirmed COVID-19 infection were assessed at baseline (~6 months post COVID-19) and follow-up (~15 months later) visits. Assessments included measures across multiple cognitive domains and self-report questionnaires of fatigue, mood, and overall health. Analyses were conducted in three stages: at the test score level (raw and adjusted scores), at the cognitive domain level, and stratified by hospitalization status during infection. Results at the test-score level indicate that cognitive performance remains relatively stable across assessments at the group level, with no significant improvements in any adjusted test scores at follow-up. Cognitive domain analyses indicate significant reductions in attention and executive functioning impairment, while memory impairment is slower to resolve. On self-report measures, there was a significant improvement in overall health ratings at follow-up. Finally, those hospitalized during infection performed worse on timed cognitive measures across visits and accounted for a larger proportion of cases with short-term and working memory impairment at follow-up. Overall, our findings indicate that cognitive difficulties persist both at test score and cognitive domain levels in many cases of post COVID-19 condition, but evidence suggests some improvement in global measures of attention, executive functioning and overall self-rated health. Furthermore, an effect of hospitalization on cognitive symptoms post COVID-19 may be more discernible over time.