A longitudinal prospective cohort study of health-related quality of life assessment in outpatient adults with post-COVID-19 conditions

Background: Few studies have reported the long-term effects of post-COVID-19 condition (PCC) on health-related quality of life (HRQoL). We aim to assess HRQoL in outpatient adults with PCC over a 2-year period. Methods: This prospective longitudinal cohort study compared 413 PCC participants (cases) to 520 COVID-19-positive participants who recovered (controls). HRQoL was assessed with the EuroQol 5-Dimension 5-Level preference-based questionnaire (EQ-5D-5L) and fitness and frailty with the Clinical Frailty Scale (CFS) at each visit for up to 24 months. Results: Among a total of 933 participants, 413 (42.3%) met the definition of PCC (cases) and 520 (55.7%) did not (controls). Overall, there was a significant difference in EQ-5D-5L index score from 3 months post-infection up to 18 months between cases and controls (p < 0.001). This score continued to decline up to 18 months in the PCC group only. Most impaired EQ-5D-5L dimensions at 12 months in the PCC group included pain/discomfort, anxiety/depression, and usual activities. Conclusions: This is one of the first studies to report 2-year alterations of HRQoL in outpatients with PCC. Our study highlights the need for continued monitoring for PCC long-term consequences. Given the high proportion of PCC participants experiencing anxiety/depression problems, further studies are needed to specifically address mental health in this population.