Evolution of Coronavirus Disease 2019 (COVID-19) Symptoms During the First 12 Months After Illness Onset

In our cohort, post-coronavirus disease (COVID) syndrome was common, even in those with mild disease. Recovery from symptoms beyond 6 months after illness onset was rare. Importantly, female and obese participants recovered more slowly, regardless of age or comorbidities. Background Few robust longitudinal data on long-term coronavirus disease 2019 (COVID-19) symptoms are available. We evaluated symptom onset, severity and recovery across the full spectrum of disease severity, up to one year after illness onset. Methods The RECoVERED Study is a prospective cohort study based in Amsterdam, the Netherlands. Participants aged >= 18 years were enrolled following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis via the local public health service and from hospitals. Standardized symptom questionnaires were completed at enrollment, 1 week and month later, and monthly thereafter. Clinical severity was defined according to World Health Organization (WHO) criteria. Kaplan-Meier methods were used to compare time from illness onset to symptom recovery, by clinical severity. We examined determinants of time to recovery using multivariable Cox proportional hazards models. Results Between 11 May 2020 and 1 May 2021, 342 COVID-19 patients (192 [56%] male) were enrolled, of whom 99/342 (29%) had mild, 145/342 (42%) moderate, 56/342 (16%) severe, and 42/342 (12%) critical disease. The proportion of participants who reported at least 1 persistent symptom at 12 weeks after illness onset was greater in those with severe/critical disease (86.7% [95% confidence interval {CI} = 76.5-92.7%]) compared to those with mild or moderate disease (30.7% [95% CI = 21.1-40.9%] and 63.8% [95% CI = 54.8-71.5%], respectively). At 12 months after illness onset, two-fifths of participants (40.7% [95% CI = 34.2-7.1]) continued to report >= 1 symptom. Recovery was slower in female compared to male participants (adjusted hazard ratio [aHR] 0.65 [95% CI = .47-.92]) and those with a body mass index [BMI] >= 30kg/m(2) compared to BMI <25kg/m(2) (hazard ratio [HR] 0.62 [95% CI = .39-.97]). Conclusions COVID-19 symptoms persisted for one year after illness onset, even in some individuals with mild disease. Female sex and obesity were the most important determinants of speed of recovery from symptoms.