Long-Term Clinical Sequelae and Immunological Features of COVID-19 Survivors: A Cross-Sectional Study in Wuhan, China

Objectives: To describe the clinical sequelae and immunological features of COVID-19 survivors who have been discharged from the hospital for 5-8 months. Methods: This study is a cross-sectional study of confirmed COVID-19 patients aged ≥18 years who were discharged from hospitals in Wuhan from January to April 2020. The demographics, clinical features, and laboratory findings of the participants were collected from medical records in the hospital. The participants from the study completed an investigation of clinical sequelae, blood tests, a pulmonary function examination and an unarmed rehabilitation evaluation at Hubei Provincial Hospital of Traditional Chinese & Western Medicine. A group of volunteers who were free of COVID-19 and lived in Wuhan during the outbreak were recruited as the comparison group. Results: The average age of the 574 COVID-19 survivors was 57.7±11.4 years, and 348 (60.6%) survivors were female. The average number of days from the onset of symptoms was 241.79±16.16. The average number of days from discharge was 194.3±14.4. Clinical sequelae were common, including general symptoms (n=321, 55.9%), respiratory symptoms (n=265, 46.2%), digestive symptoms (n=84, 14.6%), nervous symptoms (n=75,13.1%) and psychosocial symptoms (n=201, 35%). A total of 190 (33.7%) survivors reported reduced exercise capacity. Through the results of pulmonary function examination, anomalies were noted in carbon monoxide diffusion capacity (DLCO)% in 110 cases (32.4%), maximal mid-expiratory flow (MMEF)% in 105 cases (30.7%), forced expired flow at 50% of forced vital capacity (FEF 50 )% in 128 cases (37.4%), and forced expired flow at 75% of forced vital capacity (FEF 75 )% in 240 cases (70.2%). The counts of T lymphocyte, CD4+ T lymphocyte counts, CD8+ T lymphocyte counts, B lymphocyte and NK cell in the survival group was significantly lower than that in the comparison group(all P 0.05). The T lymphocyte counts, CD4+ T lymphocyte counts and CD8+ T lymphocyte counts of the patients before discharge were significantly higher than those in the early stage of admission (P < 0.025). There were 319 (55.6%) survivors with positive or weakly positive IgG antibodies and 17 (2.9%) survivors with positive or weakly positive IgM antibodies. Conclusion: Even after 5 to 8 months of discharge, many survivors still have clinical sequelae, and some of them have impaired immune function. Therefore, the long-term rehabilitation of COVID-19 survivors remains a concern. Funding Statement: This study was funded by the National Key R&D Plan of China (2020YFC0841600), Guangdong Provincial Key Laboratory of Research on Emergency in TCM (2017B030314176), R&D plan in key areas of Guangdong Province (2020B1111300005), and National Administration of Traditional Chinese Medicine (2020ZYLCYJ05-11). Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study was approved by the ethical committees of Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China (GPHCM; No. BF2020-205-01). All participants signed informed consent forms.