Prevalence and trends in persistent symptoms following COVID-19 in Japan: A nationwide cross-sectional survey

Introduction: Even during the endemic phase of the COVID-19 pandemic, the impact of persistent symptoms on patients and healthcare systems remains significant. Thus, a more comprehensive understanding of these symptoms is essential. Methods: Using data from the Japan Society and New Tobacco Internet Survey conducted in February 2023, this cross-sectional study investigated the prevalence of, and changes in, persistent COVID-19 symptoms. Results: In total, 21,108 individuals responded to the survey. Of these, 29.1 % (6143) had a history of COVID-19. Our analysis found that arm/leg/joint pain (adjusted odds ratio [aOR]: 1.17; 95 % confidence interval [95 % CI]: 1.03-1.33), back pain (aOR: 1.13; 95 % CI: 1.01-1.27), chest pain (aOR: 1.53; 95 % CI: 1.20-1.96), malaise (aOR: 1.14; 95 % CI: 1.02-1.28), loss of taste (aOR: 2.55; 95 % CI: 1.75-3.72), loss of smell (aOR: 2.33; 95 % CI: 1.67-3.26), memory impairment (aOR: 1.27; 95 % CI: 1.04-1.56), and cough (aOR: 1.72; 95 % CI: 1.38-2.13) were independently associated with a history of COVID-19 contracted more than two months but less than six months previously. Further, back pain (aOR: 1.24; 95 % CI: 1.04-1.47) and loss of taste (aOR: 2.28; 95 % CI: 1.24-4.21) showed independent association with COVID-19 contracted more than 12 months previously. Conclusions: Various symptoms were independently associated with a history of COVID-19. While most patients tend to recover within a year after contracting COVID-19, certain symptoms, such as back pain and loss of taste, persist longer than a year, underscoring public health concerns and emphasizing the need for health care services to support patients suffering from persistent symptoms.