Persistent Symptoms After Acute COVID-19 Infection in Omicron Era

BACKGROUND: We aim to compare the clinical characteristics and subjectively reported symptoms of the acute coronavirus disease (COVID) phase and those of the post-acute COVID phase to examine varying factors that affect the number of persistent symptoms and their categories. METHODS: We categorized 1,122 patients who visited the post coronavirus disease 2019 (COVID-19) clinic into two groups: “acute group” (< 4 weeks following diagnosis of COVID-19) and “post-acute group” (> 4 weeks following diagnosis of COVID-19). We statistically compared clinical characteristics between the two groups and determined which factors are associated with the number of persistent symptoms and their categories. RESULTS: The persistent symptoms of post COVID-19 conditions were classified into three categories as follows: Category A (the prevalence of symptoms is higher in the acute-visit group than in the post-acute-visit group), Category B (the prevalence of symptoms is not different between the two groups) and Category C (the prevalence of symptoms is higher in the post-acute-visit group than in the acute-visit group). Category A mainly included respiratory symptoms. Category B had generalized weakness, weight loss, cardiologic symptoms, hypogeusia, hyposmia, anxiety, and various gastrointestinal symptoms. Category C included fatigue, decreased attention, depression, blurred vision, hair loss, and sexual dysfunction. Anxiety, depression, fatigue and age were also associated with the number of symptoms and their categories, and anxiety is the most correlated factor (P < 0.001) among them. CONCLUSION: The persistent symptoms of post COVID-19 condition involve multi-organ and continue for four weeks or greater. Therefore, long-term observation and multidisciplinary interventions are essential for patients with post COVID-19 conditions.