Exploring the characteristics and antecedents of clinically significant long COVID: A longitudinal cohort study

Background: A significant number of coronavirus disease 2019 (COVID-19) survivors are experiencing long COVID, with symptoms lasting beyond three months. While diverse long COVID symptoms are established, there are gaps in understanding its long-term trends, intensity, and risk factors, requiring further investigation.

Aims: This study aimed to investigate the long COVID characteristics and associated factors by following COVID-19 survivors for one year post-infection and comparing them with healthy counterparts.

Main methods: In this longitudinal, correlational study, COVID-19 survivors diagnosed between November 2021 and February 2023 were monitored every three months for a year. Participants aged ≥18 years who had reported a positive COVID-19 test were recruited via social media and healthcare provider referrals.

Key findings: Out of 182 survivors who initially agreed to participate, 176 completed the study. The mean age was 47.56 years (SD = 16.2), and 51.1 % were female. There was a clinically significant decline in cognitive function and health-related quality of life over time, with symptoms like shortness of breath, reduced physical fitness, and increased health concerns. Those with severe acute COVID-19 symptoms experienced greater cognitive and physical declines and more shortness of breath a year later. Lower financial status was linked to poorer health-related quality of life and increased health concerns.

Significance: A year post-infection, COVID-19's impact on cognitive function and health-related quality of life remains significant, affecting individuals and communities. Survivors with severe initial symptoms and economic disadvantages need more attention. Future research should identify additional predictors of severe long COVID.