Characteristics of Long COVID: Cases from the First to the Fifth Wave in Greater Tokyo, Japan

Purpose: Approximately 25–60% of COVID-19 patients develop long-term sequelae of the condition known as long COVID. This study aimed to examine sociodemographic and clinical characteristics of long COVID in Japan. Methods: The data of long COVID patients, defined as those who were symptomatic after 28 days from onset, were collected in an outpatient clinic in Tokyo, Japan between 6 January 2020 and 2 October 2021 (N = 1891). Information on age, sex, employment, infection waves, vaccination, impairment in activities of daily living, and symptoms were obtained from electronic medical records. We used linear regression to analyze the association of patients characteristics with performance status. Results: The mean number of days from onset was 77.6 (SD: 71.3). Female, those who had their work hours reduced, on leave, dismissed or retired or not working, were associated with lower performance status. Fatigue, depressive symptom, brain fog, dyspnea, palpitation, body pain, loss of appetite, fever—but not headache, insomnia, loss of smell, loss of taste, hair loss, or cough—were associated with the lower performance status. Conclusion: Sex and employment status were associated with lower performance status in long COVID patients. Studies are needed to elucidate the full picture of the characteristics of long COVID patients.