Persistent COVID-19 symptoms and associated factors in a tertiary hospital in Thailand

Coronavirus disease 2019 (COVID-19) is associated with long-term symptoms, but the spectrum of these symptoms remains unclear. We aimed to identify the prevalence and factors associated with persistent symptoms in patients at the post-COVID-19 outpatient clinic.

This cross-sectional, observational study included hospitalized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected patients followed-up at a post-COVID-19 clinic between September 2021 and January 2022. Persistent symptoms, defined as lasting > 4 weeks after infection, were analyzed alongside symptom timing (28-90, 91-120, and > 120 days) and associated factors using multivariate analysis.

Among 277 patients, mean (SD) age was 56 (16.6) years, and 58.5% were male. Of these, 80.9% reported at least one persistent symptom. Common symptoms included dyspnea (48.2%), insomnia (42.4%), and myalgia (42.1%). In multivariate analysis, being female [odds ratio (OR) 3.41; 95% confidence interval (CI) 1.5-7.76], and oxygen therapy (OR 3.39; 95% CI 1.3-8.81) were independently associated factors with persistent symptoms. High-sensitivity C-reactive protein (HsCRP) (> 75 mg/dL) was an independent risk factor for dyspnea (adjusted OR 2.29; 95% CI 1.28-4.12), and fatigue (adjusted OR 2.24; 95% CI 1.25-4). Oxygen therapy was an independent risk factor for neurologic symptoms, i.e. insomnia (adjusted OR 2.05; 95% CI 1.15-3.65), and brain fog (adjusted OR 2.02; 95% CI 1.14-3.58).

There was a high prevalence of persistent COVID-19 symptoms. The most common symptom was dyspnea. Female gender and oxygen supplementation were independent associated factors. Continuous follow-up of these patients is still required.