Impact of Long COVID on the Health-Related Quality of Life of Japanese Patients: A Prospective Nationwide Cohort Study

Abstract

Background: Various prolonged systemic symptoms, forming the long coronavirus disease (COVID), have been observed in patients who have recovered from the acute phase of COVID-19. Although previous studies have reported that COVID-19 impacts health-related quality of life (HRQoL), the associations of long COVID symptoms and clinical characteristics with HRQoL remain unclear. This study aimed to clarify these associations in patients with long COVID using nationwide Japanese epidemiological data. Methods: A prospective nationwide cohort study was conducted on patients aged ≥ 18 years admitted and discharged with a confirmed diagnosis of COVID-19 from January 2020 to the end of February 2021 at 26 participating medical institutions in Japan. Various long COVID symptoms and HRQoL scores at 3, 6, and 12 months following diagnosis were collected, and 986 participants were included. Generalized estimating equations (GEE) were used to explore the association between HRQoL scores evaluated using the short form-8 (SF-8), long COVID symptoms, and baseline clinical characteristics. Results: Patients who had at least one long COVID symptom showed a significantly lower physical component summary score (PCS) and mental component summary score (MCS) compared with those without any symptoms at 3, 6, and 12 months after diagnosis. GEE revealed that long COVID-19 symptoms, including dyspnea, fatigue, headache, and muscle weakness, were significantly associated with worse PCS, whereas poor concentration, sleep disorders, fatigue, and headache were significantly associated with worse MCS. Comorbidities, including cardiovascular disease and asthma, and severity-related baseline parameters for patients with COVID-19, such as severe outcomes during hospitalization and oxygen requirement, were significantly associated with worse PCS scores, though these factors were not significantly associated with worse MCS scores. Conclusions: Patients with various long COVID symptoms have lower physical and mental HRQoL. Severe outcomes of COVID-19 during hospitalization and comorbidities had an impact on PCS, but these factors did not affect MCS.