Post-COVID health-related quality of life and somatic symptoms: A national survey in Japan

Background: The characteristics and risk factors of post-COVID-19 condition affecting health-related quality of life and the symptom burden are unclear. Methods: The present, cross-sectional study used the JASTIS (Japan Society and New Tobacco Internet Survey) database. EQ-5D-5L and Somatic Symptom Scale-8 were used to assess health-related quality of life and somatic symptoms, respectively. The participants were classified into a no-COVID-19, COVID-19 not requiring oxygen therapy or COVID-19 requiring oxygen therapy group. First, the entire cohort was analyzed. Then, sensitivity analysis was performed after excluding patients in the no-COVID-19 group with a history of close contact with individuals known to have the disease. Findings: In total, 30130 individuals (mean age: 47.8; females: 51.2%), including 539 and 805 with COVID-19 requiring and not requiring oxygen therapy, respectively, participated. The analysis of the entire cohort as well as the sensitivity analysis demonstrated that individuals with a history of COVID-19 had significantly lower EQ-5D-5L and significantly higher SSS-8 scores than those with no COVID-19 history. The group requiring oxygen therapy was associated with significantly lower EQ-5D-5L and higher SSS-8 scores than the group not requiring oxygen therapy. Propensity-score matching confirmed these results. Furthermore, two or more COVID-19 vaccinations were independently associated with high EQ-5D-5L and low SSS-8 scores (P < 0.001). Conclusions: The participants with a COVID-19 history, especially those with severe disease, had a significantly higher somatic symptom burden. Analysis after adjusting for potential confounders found that their quality-of-life was also severely affected. Vaccination is crucial to addressing these symptoms, especially in high-risk patients.