6-month consequences of COVID-19 in patients discharged from hospital: a cohort study.

BACKGROUND: The long-term health consequences of COVID-19 remain largely unclear. The aim of this study was to describe the long-term health consequences of patients with COVID-19 who have been discharged from hospital and investigate the associated risk factors, in particular disease severity. METHODS: We did an ambidirectional cohort study of patients with confirmed COVID-19 who had been discharged from Jin Yin-tan Hospital (Wuhan, China) between Jan 7 and May 29, 2020. Patients who died before follow-up; patients for whom follow-up would be difficult because of psychotic disorders, dementia, or readmission to hospital; those who were unable to move freely due to concomitant osteoarthropathy or immobile before or after discharge due to diseases such as stroke or pulmonary embolism; those who declined to participate; those who could not be contacted; and those living outside of Wuhan or in nursing or welfare homes were all excluded. All patients were interviewed with a series of questionnaires for evaluation of symptoms and health-related quality of life, underwent physical examinations and a 6-min walking test, and received blood tests. A stratified sampling procedure was used to sample patients according to their highest seven-category scale during their hospital stay as 3, 4, and 5-6, to receive pulmonary function test, high resolution CT of the chest, and ultrasonography. Enrolled patients who had participated in the Lopinavir Trial for Suppression of SARS-CoV-2 in China received SARS-CoV-2 antibody tests. Multivariable adjusted linear or logistic regression models were used to evaluate the association between disease severity and long-term health consequences. FINDINGS: In total, 1733 of 2469 discharged patients with COVID-19 were enrolled after 736 were excluded. Patients had a median age of 57·0 years (IQR 47·0-65·0) and 897 (52%) were male and 836 (48%) were female. The follow-up study was done from June 16 to Sept 3, 2020, and the median follow-up time after symptom onset was 186·0 days (175·0-199·0). Fatigue or muscle weakness (52%, 855 of 1654) and sleep difficulties (26%, 437 of 1655) were the most common symptoms. Anxiety or depression was reported among 23% (367 of 1616) of patients. The proportions of 6-min walking distance less than the lower limit of the normal range were 17% for those at severity scale 3, 13% for severity scale 4, and 28% for severity scale 5-6. The corresponding proportions of patients with diffusion impairment were 22% for severity scale 3, 29% for scale 4, and 56% for scale 5-6, and median CT scores were 3·0 (IQR 2·0-5·0) for severity scale 3, 4·0 (3·0-5·0) for scale 4, and 5·0 (4·0-6·0) for scale 5-6. After multivariable adjustment, patients showed an odds ratio (OR) of 1·61 (95% CI 0·80-3·25) for scale 4 versus scale 3 and 4·60 (1·85-11·48) for scale 5-6 versus scale 3 for diffusion impairment; OR 0·88 (0·66-1·17) for scale 4 versus scale 3 and OR 1·76 (1·05-2·96) for scale 5-6 versus scale 3 for anxiety or depression, and OR 0·87 (0·68-1·11) for scale 4 versus scale 3 and 2·75 (1·61-4·69) for scale 5-6 versus scale 3 for fatigue or muscle weakness. Of 94 patients with blood antibodies tested at follow-up, the seropositivity (96·2% vs 58·5%) and median titres (19·0 vs 10·0) of the neutralising antibodies were significantly lower compared with at the acute phase. 107 of 822 participants without acute kidney injury and with an estimated glomerular filtration rate (eGFR) of 90 mL/min per 1·73 m2 or more at acute phase had eGFR less than 90 mL/min per 1·73 m2 at follow-up. INTERPRETATION: At 6 months after acute infection, COVID-19 survivors were mainly troubled with fatigue or muscle weakness, sleep difficulties, and anxiety or depression. Patients who were more severely ill during their hospital stay had more severe impaired pulmonary diffusion capacities and abnormal chest imaging manifestations, and are the main target population for intervention of long-term recovery. FUNDING: National Natural Science Foundation of China, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, National Key Research and Development Program of China, Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis, and Peking Union Medical College Foundation.

Risk factors associated with functional decline in older hospital survivors with acute lower respiratory tract infections: a prospective cohort study.

OBJECTIVE: To evaluate the dynamics of basic activity of daily living (BADL) in older patients with acute lower respiratory tract infections (LRTIs) during acute phase and to investigate risk factors associated with decreased physical function at discharge. METHODS: We conducted a prospective cohort study of patients aged 65 years and older who were hospitalized for acute LRTIs between April 15, 2020 and January 15, 2023. All patients received geriatric assessment at admission, including emotion, cognition, frailty, physical function status and so on. The BADL was also evaluated by the Barthel Index (BI) at two weeks before admission by recall (baseline status), at admission and at discharge. Based on the BI grades at baseline and at discharge, patients were classified into two groups: ADL decline and no ADL decline. Multivariable adjusted logistic regression models were used to evaluate the risk factors of decreased physical function. RESULTS: A total of 364 older survivors with LRTIs were included in the analysis. The median age was 74 years (IQR 61.0-82.0), 231 (62.6%) were male, the median length of stay was 10 days. In the geriatric assessment, 139 patients (38.2%) were classified as frailty, 137 patients (37.6%) experienced insomnia, 60 patients (16.5%) exhibited cognitive impairments, and 37 patients (10.2%) were defined as malnutrition. Additionally, 30 patients (8.2%) dealt with emotional disorders. On average, patients were taking 3 medications, and Charlson Comorbidity Index score was 4. 72 patients (19.8%) had function decline at discharge. In the multivariable analysis, frailty status had an odds ratio of 4.25 (95% CI 1.31-19.26) for decreased physical function and cognitive impairment had an odds ratio of 2.58 (95% CI 1.27-5.19). CONCLUSIONS: About 20% older patients with LRTIs experienced functional decline at discharge. Compared to age, severity of diseases and length of stay, frailty and cognitive impairment performed better at predicting the function decline. The apply of geriatric assessment may contribute to enhance the quality of management and treatment for patients with the older with LRTIs.

Association between cardiopulmonary bypass time and mortality among patients with acute respiratory distress syndrome after cardiac surgery.

BACKGROUND: Cardiopulmonary bypass (CPB) can lead to lung injury and even acute respiratory distress syndrome (ARDS) through triggering systemic inflammatory response. The objective of this study was to investigate the impact of CPB time on clinical outcomes in patients with ARDS after cardiac surgery. METHODS: Totally, patients with ARDS after cardiac surgery in Beijing Anzhen Hospital from January 2005 to December 2015 were retrospectively included and were further divided into three groups according to the median time of CPB. The primary endpoints were the ICU mortality and in-hospital mortality, and ICU and hospital stay. Restricted cubic spline (RCS), logistic regression, cox regression model, and receiver operating characteristic (ROC) curve were adopted to explore the relationship between CPB time and clinical endpoints. RESULTS: A total of 54,217 patients underwent cardiac surgery during the above period, of whom 210 patients developed ARDS after surgery and were finally included. The ICU mortality and in-hospital mortality were 21.0% and 41.9% in all ARDS patients after cardiac surgery respectively. Patients with long CPB time (CPB time ≥ 173 min) had longer length of ICU stay (P = 0.011), higher ICU (P < 0.001) mortality and in-hospital(P = 0.002) mortality compared with non-CPB patients (CPB = 0). For each ten minutes increment in CPB time, the hazards of a worse outcome increased by 13.3% for ICU mortality and 9.3% for in-hospital mortality after adjusting for potential factors. ROC curves showed CPB time presented more satisfactory power to predict mortality compared with APCHEII score. The optimal cut-off value of CPB time were 160.5 min for ICU mortality and in-hospital mortality. CONCLUSIONS: Our findings demonstrated the significant prognostic value of CPB time in patients with ARDS after cardiac surgery. Longer time of CPB was associated with poorer clinical outcomes, and could be served as an indicator to predict short-term mortality in patients with ARDS after cardiac surgery.

1-year outcomes in hospital survivors with COVID-19: a longitudinal cohort study.

BACKGROUND: The full range of long-term health consequences of COVID-19 in patients who are discharged from hospital is largely unclear. The aim of our study was to comprehensively compare consequences between 6 months and 12 months after symptom onset among hospital survivors with COVID-19. METHODS: We undertook an ambidirectional cohort study of COVID-19 survivors who had been discharged from Jin Yin-tan Hospital (Wuhan, China) between Jan 7 and May 29, 2020. At 6-month and 12-month follow-up visit, survivors were interviewed with questionnaires on symptoms and health-related quality of life (HRQoL), and received a physical examination, a 6-min walking test, and laboratory tests. They were required to report their health-care use after discharge and work status at the 12-month visit. Survivors who had completed pulmonary function tests or had lung radiographic abnormality at 6 months were given the corresponding tests at 12 months. Non-COVID-19 participants (controls) matched for age, sex, and comorbidities were interviewed and completed questionnaires to assess prevalent symptoms and HRQoL. The primary outcomes were symptoms, modified British Medical Research Council (mMRC) score, HRQoL, and distance walked in 6 min (6MWD). Multivariable adjusted logistic regression models were used to evaluate the risk factors of 12-month outcomes. FINDINGS: 1276 COVID-19 survivors completed both visits. The median age of patients was 59·0 years (IQR 49·0-67·0) and 681 (53%) were men. The median follow-up time was 185·0 days (IQR 175·0-198·0) for the 6-month visit and 349·0 days (337·0-361·0) for the 12-month visit after symptom onset. The proportion of patients with at least one sequelae symptom decreased from 68% (831/1227) at 6 months to 49% (620/1272) at 12 months (p<0·0001). The proportion of patients with dyspnoea, characterised by mMRC score of 1 or more, slightly increased from 26% (313/1185) at 6-month visit to 30% (380/1271) at 12-month visit (p=0·014). Additionally, more patients had anxiety or depression at 12-month visit (26% [331/1271] at 12-month visit vs 23% [274/1187] at 6-month visit; p=0·015). No significant difference on 6MWD was observed between 6 months and 12 months. 88% (422/479) of patients who were employed before COVID-19 had returned to their original work at 12 months. Compared with men, women had an odds ratio of 1·43 (95% CI 1·04-1·96) for fatigue or muscle weakness, 2·00 (1·48-2·69) for anxiety or depression, and 2·97 (1·50-5·88) for diffusion impairment. Matched COVID-19 survivors at 12 months had more problems with mobility, pain or discomfort, and anxiety or depression, and had more prevalent symptoms than did controls. INTERPRETATION: Most COVID-19 survivors had a good physical and functional recovery during 1-year follow-up, and had returned to their original work and life. The health status in our cohort of COVID-19 survivors at 12 months was still lower than that in the control population. FUNDING: Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, the National Natural Science Foundation of China, the National Key Research and Development Program of China, Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis, the China Evergrande Group, Jack Ma Foundation, Sino Biopharmaceutical, Ping An Insurance (Group), and New Sunshine Charity Foundation.

6-month consequences of COVID-19 in patients discharged from hospital: a cohort study.

BACKGROUND: The long-term health consequences of COVID-19 remain largely unclear. The aim of this study was to describe the long-term health consequences of patients with COVID-19 who have been discharged from hospital and investigate the associated risk factors, in particular disease severity. METHODS: We did an ambidirectional cohort study of patients with confirmed COVID-19 who had been discharged from Jin Yin-tan Hospital (Wuhan, China) between Jan 7, 2020, and May 29, 2020. Patients who died before follow-up, patients for whom follow-up would be difficult because of psychotic disorders, dementia, or re-admission to hospital, those who were unable to move freely due to concomitant osteoarthropathy or immobile before or after discharge due to diseases such as stroke or pulmonary embolism, those who declined to participate, those who could not be contacted, and those living outside of Wuhan or in nursing or welfare homes were all excluded. All patients were interviewed with a series of questionnaires for evaluation of symptoms and health-related quality of life, underwent physical examinations and a 6-min walking test, and received blood tests. A stratified sampling procedure was used to sample patients according to their highest seven-category scale during their hospital stay as 3, 4, and 5-6, to receive pulmonary function test, high resolution CT of the chest, and ultrasonography. Enrolled patients who had participated in the Lopinavir Trial for Suppression of SARS-CoV-2 in China received severe acute respiratory syndrome coronavirus 2 antibody tests. Multivariable adjusted linear or logistic regression models were used to evaluate the association between disease severity and long-term health consequences. FINDINGS: In total, 1733 of 2469 discharged patients with COVID-19 were enrolled after 736 were excluded. Patients had a median age of 57·0 (IQR 47·0-65·0) years and 897 (52%) were men. The follow-up study was done from June 16, to Sept 3, 2020, and the median follow-up time after symptom onset was 186·0 (175·0-199·0) days. Fatigue or muscle weakness (63%, 1038 of 1655) and sleep difficulties (26%, 437 of 1655) were the most common symptoms. Anxiety or depression was reported among 23% (367 of 1617) of patients. The proportions of median 6-min walking distance less than the lower limit of the normal range were 24% for those at severity scale 3, 22% for severity scale 4, and 29% for severity scale 5-6. The corresponding proportions of patients with diffusion impairment were 22% for severity scale 3, 29% for scale 4, and 56% for scale 5-6, and median CT scores were 3·0 (IQR 2·0-5·0) for severity scale 3, 4·0 (3·0-5·0) for scale 4, and 5·0 (4·0-6·0) for scale 5-6. After multivariable adjustment, patients showed an odds ratio (OR) 1·61 (95% CI 0·80-3·25) for scale 4 versus scale 3 and 4·60 (1·85-11·48) for scale 5-6 versus scale 3 for diffusion impairment; OR 0·88 (0·66-1·17) for scale 4 versus scale 3 and OR 1·77 (1·05-2·97) for scale 5-6 versus scale 3 for anxiety or depression, and OR 0·74 (0·58-0·96) for scale 4 versus scale 3 and 2·69 (1·46-4·96) for scale 5-6 versus scale 3 for fatigue or muscle weakness. Of 94 patients with blood antibodies tested at follow-up, the seropositivity (96·2% vs 58·5%) and median titres (19·0 vs 10·0) of the neutralising antibodies were significantly lower compared with at the acute phase. 107 of 822 participants without acute kidney injury and with estimated glomerular filtration rate (eGFR) 90 mL/min per 1·73 m2 or more at acute phase had eGFR less than 90 mL/min per 1·73 m2 at follow-up. INTERPRETATION: At 6 months after acute infection, COVID-19 survivors were mainly troubled with fatigue or muscle weakness, sleep difficulties, and anxiety or depression. Patients who were more severely ill during their hospital stay had more severe impaired pulmonary diffusion capacities and abnormal chest imaging manifestations, and are the main target population for intervention of long-term recovery. FUNDING: National Natural Science Foundation of China, Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, National Key Research and Development Program of China, Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis, and Peking Union Medical College Foundation.

"Obesity Paradox" in Acute Respiratory Distress Syndrome Among Patients Undergoing Cardiac Surgery: A Retrospective Study.

BACKGROUND The "obesity paradox" exists in many diseases. It is unclear whether it also exists in acute respiratory distress syndrome (ARDS). The purpose of our study was to clarify the relationship between obesity and the development of and hospital mortality from ARDS among patients who underwent cardiac surgery. MATERIAL AND METHODS This retrospective case-control study included 202 patients with ARDS and 808 matching patients without ARDS. We clarified the relationship between obesity and the development of ARDS after adjusting for confounding factors by multiple logistic regression analysis. A total of 202 ARDS patients were divided into survival and mortality groups. After all confounding factors were adjusted by multiple logistic regression analysis, we demonstrated the relationship between obesity and mortality from ARDS. RESULTS We found a significant association between body mass index (BMI) and the development of ARDS; the cutoff point of BMI was 24.78 kg/m² by adjusting for confounding factors for the development of ARDS. When the BMI was lower than 24.78 kg/m², the higher BMI was a protective factor (odds ratio [OR] 0.68, P=0.000, 95% confidence interval [CI] 0.55-0.84). When the BMI was higher than 24.78 kg/m², the higher BMI was a risk factor (OR 1.07, P=0.050, 95% CI 1.00-1.14). However, obesity was found to be associated with decreased ARDS mortality by adjusting for confounding factors (OR 0.91, P=0.039, 95% CI 0.83-1.00). CONCLUSIONS An "obesity paradox" may exist in ARDS among patients with obesity who undergo cardiac surgery.

A Nomogram to Predict Acute Respiratory Distress Syndrome After Cardiac Surgery.

PURPOSE: To establish a model to predict the risk of acute respiratory distress syndrome (ARDS) after cardiac surgery. METHODS: Data were collected on 132 ARDS patients, who received valvular or coronary artery bypass grafting surgery from January 2009 to December 2019. We developed the prediction model by multivariable logistic regression. Then, we used the coefficients for developing a nomogram that predicts ARDS occurrence. Internal validation was performed using resampling techniques to evaluate and optimize the model. RESULTS: All variables fit into the model, including albumin level before surgery (odds ratio [OR]: 0.96; 95% confidence interval [CI]: 0.92, 0.99; P = .01), cardiopulmonary bypass time (OR: 1.01; 95% CI: 1.00, 1.02; P = .02), APACHE II after surgery (OR: 1.21; 95% CI: 1.13, 1.29; P < .001), and history of diabetes (OR: 2.31; 95% CI: 1.88, 3.87; P < .001); these were considered to build the nomogram. The score distinguished ARDS patients from non-ARDS patients with an AUC of 0.785 (95% CI: 0.740, 0.830) and was well calibrated (Hosmer-Lemeshow P = .53). CONCLUSIONS: Our developed model predicted ARDS in patients undergoing cardiac surgery and may serve as a tool for identifying patients at high risk for ARDS after cardiac surgery.

Downregulated microRNA-27b attenuates lipopolysaccharide-induced acute lung injury via activation of NF-E2-related factor 2 and inhibition of nuclear factor κB signaling pathway.

Acute lung injury (ALI) is a life-threatening, diffuse heterogeneous lung injury characterized by acute onset, pulmonary edema, and respiratory failure. Lipopolysaccharide (LPS) is a leading cause for ALI and when administered to a mouse it induces a lung phenotype exhibiting some of the clinical characteristics of human ALI. This study focused on investigating whether microRNA-27b (miR-27b) affects ALI in a mouse model established by LPS-induction and to further explore the underlying mechanism. After model establishment, the mice were treated with miR-27b agomir, miR-27b antagomir, or D-ribofuranosylbenzimidazole (an inhibitor of nuclear factor-E2-related factor 2 [Nrf2]) to determine levels of miR-27b, Nrf2, nuclear factor kappa-light-chain-enhancer of activated B cells nuclear factor κB (NF-κB), p-NF-κB, and heme oxygenase-1 (HO-1). The levels of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid (BALF) were determined. The results of luciferase activity suggested that Nrf2 was a target gene of miR-27b. It was indicated that the Nrf2 level decreased in lung tissues from ALI mice. The downregulation of miR-27b decreased the levels of IL-1ß, IL-6, and TNF-α in BALF of ALI mice. Downregulated miR-27b increased Nrf2 level, thus enhancing HO-1 level along with reduction of NF-κB level as well as the extent of NF-κB phosphorylation in the lung tissues of the transfected mice. Pathological changes were ameliorated in LPS-reduced mice elicited by miR-27b inhibition. The results of this study demonstrate that downregulated miR-27b couldenhance Nrf2 and HO-1 expressions, inhibit NF-κB signaling pathway, which exerts a protective effect on LPS-induced ALI in mice.

LL-37 and its analog FF/CAP18 attenuate neutrophil migration in sepsis-induced acute lung injury.

INTRODUCTION: Sepsis can result in acute lung injury. LL-37 is a small cationic host defense peptide involved in anti-inflammatory. In the current study, it was hypothesized that antimicrobial peptide LL-37 could play a protective role in attenuating the progression of sepsis-induced acute lung injury. METHODS: Forty male C57BL/6 mice were induced into sepsis using cecal ligation and puncture, and subsequently administered with recombinant mouse osteopontin. Peptides LL-37, the LL-37 analog (FF/CAP18, called sLL-37), or normal saline was intravenously administered into septic mice for 20 hours. Then, proinflammatory cytokines (IL-6 and IL-1ß), acute lung injury markers (alanine aminotransferase [ALT], aspartate aminotransferase [AST], and lactate dehydrogenase [LDH]), the neutrophil infiltration marker (myeloperoxidase [MPO]), and neutrophil infiltration were detected. Furthermore, the neutrophil migration and expression of migration-related factors (focal adhesion kinase [FAK], ERK, and P38) in differentiated HL-60 cells were detected. RESULTS: Septic mice had upregulated IL-6, IL-1ß, ALT, AST, LDH, MPO, p-FAK, p-ERK, and p-P38, infiltrated neutrophils, and migrated neutrophil-like HL-60 cells. In contrast, the administration of peptide LL-37 and sLL-37 inhibited all these changes. Compared with septic mice, it was found that proinflammatory cytokines, lung injury markers, MPO, and infiltrated neutrophils decreased in mice treated with LL-37 and sLL-37. In addition, the migrated neutrophil-like HL-60 cells and activated p-FAK, p-ERK, and p-P38 proteins were suppressed by LL-37 and sLL-37 treatments. CONCLUSIONS: Peptide LL-37 and its analog sLL-37 attenuated the progression of sepsis-induced acute lung injury by inhibiting neutrophil infiltration and migration through the FAK, ERK, and P38 pathways.

Association of Monocyte Count With Lung Function and Exercise Capacity Among Hospitalized COVID-19 Survivors: A 2-Year Cohort Study.

BACKGROUND: Abnormal changes of monocytes have been observed in acute COVID-19, whereas associations of monocyte count with long COVID were not sufficiently elucidated. METHODS: A cohort study was conducted among COVID-19 survivors discharged from hospital. The primary outcomes were core symptoms of long COVID, distance walked in 6 min, and lung function, and the secondary outcomes were health-related quality of life and healthcare use after discharge. Latent variable mixture modeling was used to classify individuals into groups with similar trajectory of monocyte count from discharge to 2-year after symptom onset. Multivariable adjusted generalized linear regression models and logistic regression models were used to estimate the associations of monocyte count trajectories and monocyte count at discharge with outcomes. RESULTS: In total, 1389 study participants were included in this study. Two monocyte count trajectories including high to normal high and normal trajectory were identified. After multivariable adjustment, participants in high to normal high trajectory group had an odds ratio (OR) of 2.52 (95% CI, 1.44-4.42) for smell disorder, 2.27 (1.27-4.04) for 6-min walking distance less than lower limit of normal range, 2.45 (1.08-5.57) for total lung capacity (TLC) < 80% of predicted, 3.37 (1.16-9.76) for personal care problem, and 1.70 (1.12-2.58) for rehospitalization after discharge at 2-year follow-up compared with those in normal trajectory group. Monocyte count at discharge showed similar results, which was associated with smell disorder, TLC < 80% of predicted, diffusion impairment, and rehospitalization. CONCLUSIONS: Monocyte count may serve as an easily accessible marker for long-term management of people recovering from COVID-19.

Recurrent and persistent fever after SARS-CoV-2 infection in patients with follicular lymphoma: A case series.

Although persistent or recurrent COVID-19 infection is well described in some immunosuppressed patient cohort, to date, there have been no reports of this phenomenon in the context of repeatedly negative SARS-CoV-2 testing in the upper respiratory tract. We reported six patients with follicular lymphoma who developed recurrent symptomatic COVID-19 infection. They tested persistently negative for SARS-CoV-2 on pharyngeal swabs and ultimately confirmed by bronchoalveolar lavage fluid metagenomics next-generation sequencing. All six patients presented with lymphopenia and B-cell depletion, and five of them received the anti-cluster of differentiation 20 treatment in the last year. Persistent fever was the most common symptom and bilateral ground-glass opacities were the primary pattern on chest computed tomography. A relatively long course of unnecessary and ineffective antibacterial and/or antifungal treatments was administered until the definitive diagnosis. Persistent fever subsided rapidly with nirmatrelvir/ritonavir treatment. Our case highlighted that recurrent COVID-19 infection should be suspected in immunocompromised patients with persistent fever despite negative pharyngeal swabs, and urgent bronchoalveolar lavage fluid testing is necessary. Treatment with nirmatrelvir/ritonavir appeared to be very effective in these patients.

Immune Responses in Discharged COVID-19 Patients With and Without Long COVID Symptoms.

The immune mechanisms of long coronavirus disease 2019 (COVID) are not yet fully understood. We aimed to investigate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific memory immune responses in discharged COVID-19 patients with and without long COVID symptoms. In this cross-sectional study, we included 1041 hospitalized COVID-19 patients with the original virus strain in Wuhan (China) 12 months after initial infection. We simultaneously conducted a questionnaire survey and collected peripheral blood samples from the participants. Based on the presence or absence of long COVID symptoms during the follow-up period, we divided the patients into 2 groups: a long COVID group comprising 480 individuals and a convalescent group comprising 561 individuals. Both groups underwent virus-specific immunological analyses, including enzyme-linked immunosorbent assay, interferon-γ-enzyme-linked immune absorbent spot, and intracellular cytokine staining. At 12 months after infection, 98.5% (1026/1041) of the patients were found to be seropositive and 93.3% (70/75) had detectable SARS-CoV-2-specific memory T cells. The long COVID group had significantly higher levels of receptor binding domain (RBD)-immunoglobulin G (IgG) levels, presented as OD450 values, than the convalescent controls (0.40 ± 0.22 vs 0.37 ± 0.20; P = .022). The magnitude of SARS-CoV-2-specific T-cell responses did not differ significantly between groups, nor did the secretion function of the memory T cells. We did not observe a significant correlation between SARS-CoV-2-IgG and magnitude of memory T cells. This study revealed that long COVID patients had significantly higher levels of RBD-IgG antibodies when compared with convalescent controls. Nevertheless, we did not observe coordinated SARS-CoV-2-specific cellular immunity. As there may be multiple potential causes of long COVID, it is imperative to avoid adopting a "one-size-fits-all" approach to future treatment modalities.

Effect of Corticosteroids on Long-Term Humoral and Memory T-Cell Responses in Follow-Up Visit of Hospitalized Patients With COVID-19.

BACKGROUND: Corticosteroids have beneficial effects in improving outcomes in hospitalized patients with severe COVID-19 by suppressing excessive immune responses. However, the effect of corticosteroids on the humoral and T-cell responses of survivors of COVID-19 1 year after infection remains uncertain, as it relates to the extent of immediate, antigen-specific defense provided by protective memory. RESEARCH QUESTION: What is the effect of corticosteroids on long-term humoral and T-cell immune responses? STUDY DESIGN AND METHODS: In this retrospective cohort study conducted at a single center, we analyzed data from a cohort who had survived COVID-19 to compare the 1-year seropositivity and titer changes in neutralizing antibodies (NAbs) and SARS-CoV-2-specific antibodies. Additionally, we evaluated the magnitude and rate of SARS-CoV-2-specific T-cell response in individuals who received corticosteroids during hospitalization and those who did not. RESULTS: Our findings indicated that corticosteroids do not statistically influence the kinetics or seropositive rate of NAbs against the Wuhan strain of SARS-CoV-2 from 6 months to 1 year. However, subgroup analysis revealed a numerical increase of NAbs titers, from 20.0 to 28.2, in categories where long-term (> 15 days) and high-dose (> 560 mg) corticosteroids were administered. Similarly, corticosteroids showed no significant effect on nucleoprotein and receptor-binding domain IgG at 1 year, except for spike protein IgG (ß, 0.08; 95% CI, 0.04-0.12), which demonstrated a delayed decline of titers. Regarding T-cell immunity, corticosteroids did not affect the rate or magnitude of T-cell responses significantly. However, functional assessment of memory T cells revealed higher interferon-γ responses in CD4 (ß, 0.61; 95% CI, 0.10-1.12) and CD8 (ß, 0.63; 95% CI, 0.11-1.15) memory T cells in the corticosteroids group at 1 year. INTERPRETATION: Based on our findings, short-term and low-dose corticosteroid therapy during hospitalization does not appear to have a significant effect on long-term humoral kinetics or the magnitude and rate of memory T-cell responses to SARS-CoV-2 antigens. However, the potential harmful effects of long-term and high-dose corticosteroid use on memory immune responses require further investigation.

Quantitative Analysis of Mixed Minerals with Finite Phase Using Thermal Infrared Hyperspectral Technology.

It is crucial but challenging to detect intermediate or end products promptly. Traditional chemical detection methods are time-consuming and cannot detect mineral phase content. Thermal infrared hyperspectral (TIH) technology is an effective means of real-time imaging and can precisely capture the emissivity characteristics of objects. This study introduces TIH to estimate the content of potassium salts, with a model based on Competitive Adaptive Reweighted Sampling (CARS) and Partial Least Squares Regression (PLSR). The model takes the emissivity spectrum of potassium salt into account and accurately predicts the content of Mixing Potassium (MP), a mineral mixture produced in Lop Nur, Xinjiang. The main mineral content in MP was measured by Mineral Liberation Analyzer (MLA), mainly including picromerite, potassium chloride, magnesium sulfate, and less sodium chloride. 129 configured MP samples were divided into calibration (97 samples) and prediction (32 samples) sets. The CARS-PLSR method achieved good prediction results for MP mineral content (picromerite: correlation coefficient of correction set (Rp2) = 0.943, predicted root mean square error (RMSEP) = 2.72%, relative predictive deviation (RPD) = 4.24; potassium chloride: Rp2 = 0.948, RMSEP = 2.86%, RPD = 4.42). Experimental results convey that TIH technology can effectively identify the emissivity characteristics of MP minerals, facilitating quantitative detection of MP mineral content.

Probing long COVID through a proteomic lens: a comprehensive two-year longitudinal cohort study of hospitalised survivors.

BACKGROUND: As a debilitating condition that can impact a whole spectrum of people and involve multi-organ systems, long COVID has aroused the most attention than ever. However, mechanisms of long COVID are not clearly understood, and underlying biomarkers that can affect the long-term consequences of COVID-19 are paramount to be identified. METHODS: Participants for the current study were from a cohort study of COVID-19 survivors discharged from hospital between Jan 7, and May 29, 2020. We profiled the proteomic of plasma samples from hospitalised COVID-19 survivors at 6-month, 1-year, and 2-year after symptom onset and age and sex matched healthy controls. Fold-change of >2 or <0.5, and false-discovery rate adjusted P value of 0.05 were used to filter differentially expressed proteins (DEPs). In-genuity pathway analysis was performed to explore the down-stream effects in the dataset of significantly up- or down-regulated proteins. Proteins were integrated with long-term consequences of COVID-19 survivors to explore potential biomarkers of long COVID. FINDINGS: The proteomic of 709 plasma samples from 181 COVID-19 survivors and 181 matched healthy controls was profiled. In both COVID-19 and control group, 114 (63%) were male. The results indicated four major recovery modes of biological processes. Pathways related to cell-matrix interactions and cytoskeletal remodeling and hypertrophic cardiomyopathy and dilated cardiomyopathy pathways recovered relatively earlier which was before 1-year after infection. Majority of immune response pathways, complement and coagulation cascade, and cholesterol metabolism returned to similar status of matched healthy controls later but before 2-year after infection. Fc receptor signaling pathway still did not return to status similar to healthy controls at 2-year follow-up. Pathways related to neuron generation and differentiation showed persistent suppression across 2-year after infection. Among 98 DEPs from the above pathways, evidence was found for association of 11 proteins with lung function recovery, with the associations consistent at two consecutive or all three follow-ups. These proteins were mainly enriched in complement and coagulation (COMP, PLG, SERPINE1, SRGN, COL1A1, FLNA, and APOE) and hypertrophic/dilated cardiomyopathy (TPM2, TPM1, and AGT) pathways. Two DEPs (APOA4 and LRP1) involved in both neuron and cholesterol pathways showed associations with smell disorder. INTERPRETATION: The study findings provided molecular insights into potential mechanism of long COVID, and put forward biomarkers for more precise intervention to reduce burden of long COVID. FUNDING: National Natural Science Foundation of China; Chinese Academy of Medical Sciences (CAMS) Innovation Fund for Medical Sciences; Clinical Research Operating Fund of Central High Level Hospitals; the Talent Program of the Chinese Academy of Medical Science; Training Program of the Big Science Strategy Plan; Ministry of Science and Technology of the People's Republic of China; New Cornerstone Science Foundation; Peking Union Medical College Education Foundation; Research Funds from Health@InnoHK Program.

Rheumatic Symptoms Following Coronavirus Disease 2019 (COVID-19): A Chronic Post-COVID-19 Condition.

Background: Detailed characteristics of rheumatic symptoms of coronavirus disease 2019 (COVID-19) were still unknown. We aim to investigate the proportions, characteristics, and risk factors of this condition. Methods: In this prospective, longitudinal cohort study, discharged patients with COVID-19 were interviewed face-to-face at 12 months after symptom onset. Rheumatic symptoms following COVID-19 included newly occurring joint pain and/or joint swelling. The risk factors of developing rheumatic symptoms were identified by multivariable logistic regression analysis. Results: In total, 1296 of 2469 discharged patients with COVID-19 were enrolled in this study. Among them, 160 (12.3% [95% confidence interval {CI}, 10.6%-14.3%]) suffered from rheumatic symptoms following COVID-19 at 12-month follow-up. The most frequently involved joints were the knee joints (38%), followed by hand (25%) and shoulder (19%). Rheumatic symptoms were independent of the severity of illness and corticosteroid treatment during the acute phase, while elderly age (odds ratio [OR], 1.22 [95% CI, 1.06-1.40]) and female sex (OR, 1.58 [95% CI, 1.12-2.23]) were identified as the risk factors for this condition. Conclusions: Our investigation showed a considerable proportion of rheumatic symptoms following COVID-19 in discharged patients, which highlights the need for continuing attention. Notably, rheumatic symptoms following COVID-19 were independent of the severity of illness and corticosteroid treatment during the acute phase.

Association of acute kidney injury with 1-year outcome of kidney function in hospital survivors with COVID-19: A cohort study.

BACKGROUND: Kidney damage in COVID-19 patients has been of special concern. The association of acute kidney injury (AKI) with post-acute kidney function among COVID-19 survivors was not sufficiently elucidated. METHODS: An ambidirectional cohort study was conducted with enrollment of COVID-19 survivors discharged from hospital between Jan 7, and May 29, 2020. Study participants were invited to follow-up visits at 6 and 12 months after symptom onset. The primary outcome was percentage of estimated glomerular filtration rate (eGFR) decreased from acute phase (between symptom onset and hospital discharge) to follow-up, and secondary outcome was reduced renal function at follow-up. FINDINGS: In total, 1,734 study participants were included in this study. Median follow-up duration was 342.0 days (IQR, 223.0-358.0) after symptom onset. After multivariable adjustment, percentage of eGFR decreased from acute phase to follow-up was 8.30% (95% CI, 5.99-10.61) higher among AKI participants than those without AKI at acute phase. Participants with AKI had an odds ratio (OR) of 4.60 (95% CI, 2.10-10.08) for reduced renal function at follow-up. The percentage of eGFR decreased for participants with AKI stage 1, stage 2, and stage 3 was 6.02% (95% CI, 3.48-8.57), 15.99% (95% CI, 10.77-21.22), and 17.79% (95% CI, 9.14-26.43) higher compared with those without AKI, respectively. INTERPRETATION: AKI at acute phase of COVID-19 was closely related to the longitudinal decline and post-acute status of kidney function at nearly one-year after symptom onset. Earlier and more intense follow-up strategies on kidney function management could be beneficial to COVID-19 survivors. FUNDING: Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (CIFMS 2020-I2M-CoV19-005, 2018-I2M-1-003, and 2020-I2M-2-013); National Natural Science Foundation of China (82041011); National Key Research and Development Program of China (2018YFC1200102); Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis (2020ZX09201001).