Lung pathophysiology in patients with long COVID-19: one size definitely does not fit all.

Despite reduced resting lung volumes and D LCO, patients with long COVID and dyspnoea have similar physiological response to exercise to healthy subjects. D LCO impairment can marginally explain heterogeneity of complex syndromes such as long COVID. https://bit.ly/40j4aX6.

Acute Improvements of Oxygenation with Cpap and Clinical Outcomes in Severe COVID-19 Pneumonia: A Multicenter, Retrospective Study.

It is not known if the degrees of improvement in oxygenation obtained by CPAP can predict clinical outcomes in patients with COVID-19 pneumonia. This was a retrospective study conducted on patients with severe COVID-19 pneumonia treated with CPAP in three University hospitals in Milan, Italy, from March 2020 to March 2021. Arterial gas analysis was obtained before and 1 h after starting CPAP. CPAP failure included either death in the respiratory units while on CPAP or the need for intubation. Two hundred and eleven patients (mean age 64 years, 74% males) were included. Baseline median PaO2, PaO2/FiO2 ratio (P/F), and the alveolar-arterial (A-a) O2 gradient were 68 (57−83) mmHg, 129 (91−179) mmHg and 310 (177−559) mmHg, respectively. Forty-two (19.9%) patients died in the respiratory units and 51 (24.2%) were intubated. After starting CPAP, PaO2/FiO2 increased by 57 (12−113; p < 0.001) mmHg, and (A-a) O2 was reduced by 68 (−25−250; p < 0.001) mmHg. A substantial overlap of PaO2, P/F, and A-a gradient at baseline and during CPAP was observed in CPAP failures and successes; CPAP-associated improvements in oxygenation in both groups were similar. In conclusion, CPAP-associated improvements in oxygenation do not predict clinical outcomes in patients with severe COVID-19 pneumonia.

Lung ultrasound in the follow-up of severe COVID-19 pneumonia: six months evaluation and comparison with CT.

While lung ultrasonography (LUS) proved to be a useful diagnostic and prognostic tool in acute phase of COVID 19 pneumonia, its role in detecting long-term pulmonary sequelae has yet to be explored. In our prospective observational study we assessed the potential of LUS in detecting the presence of computed tomography (CT) fibrotic-like changes after 6 months from COVID-19 pneumonia. Patients who were discharged with a diagnosis of severe COVID-19 pneumonia were enrolled. After 6 months from hospital discharge they underwent LUS, chest CT scan and pulmonary function tests. A logistic regression analysis was performed to assess the association between presence of symptoms, LUS score and diffusing capacity for carbon monoxide (DLCO) at 6-month after hospital discharge and CT scan fibrotic-like changes. A second logistic model was performed to assess the value of some predefined baseline factors (age, sex, worst PaO2/FiO2, ventilator support, worst CRP value, worst D-dimer value and worst LUS score during hospitalization) to predict fibrotic-like changes on 6-month CT scan. Seventy-four patients were enrolled in the study. Twenty-four (32%) showed lung abnormalities suitable for fibrotic-like changes. At multivariate logistic regression analysis LUS score after 6 months from acute disease was significantly associated with fibrotic-like pattern on CT scan. The second logistic model showed that D-dimer value was the only baseline predictive variable of fibrotic-like changes at multivariate analysis. LUS performed after 6 months from severe COVID-19 pneumonia may be a promising tool for detection and follow-up of pulmonary fibrotic sequelae.

Continuous Positive Airway Pressure in Elderly Patients with Severe COVID-19 Related Respiratory Failure.

The elderly population represents a high percentage of patients hospitalized for COVID-19 pneumonia and severe respiratory failure, for whom CPAP may be a treatment option. The aim of this study was to describe the CPAP support modalities and to explore factors associated with CPAP failure. In this retrospective study, 110 consecutive patients aged ≥ 75 years were enrolled. Median frailty score, baseline partial arterial pressure of oxygen to fraction of inspired oxygen ratio (P/F), and respiratory rate (RR) were 5, 108, and 30 cycles/min, respectively. Of the 110 patients that began CPAP treatment, 17 patients died within 72 h from baseline, while in 2 patients, CPAP was withdrawn for clinical improvement. Thus, of the 91 patients still on CPAP at day 3, 67% of them needed continuous CPAP delivery. Patients with RR ≥ 30 and with frailty score ≥ 5 had an odds ratio of continuous CPAP needing of 3 and 4, respectively. Patients unable to tolerate CPAP-free periods demonstrated higher mortality risk as compared to those able to tolerate intermittent CPAP (OR: 6.04, 95% CI 2.38-16.46, p < 0.001). The overall in-hospital mortality was 63.6%. Delirium occurred in 59.1%, with a mortality rate in this subgroup of 83.1%. In a time-varying Cox model, the hazard ratio of death was 2.9 in patients with baseline RR ≥ 30 cycle/min, 2.4 in those with baseline P/F < 100. In the same model, the hazard ratio of death was 20 in patients with delirium and a frailty score < 5 and 8.8 in those without delirium and with frailty ≥ 5, indicating a competitive effect between these two variables on the death risk. Conclusions: Respiratory impairment, frailty, and delirium predict treatment failure, with the latter two factors demonstrating a competitive effect on mortality risk. CPAP support may represent a feasible therapeutic option in elderly patients, although chances of a therapeutic benefit are markedly reduced in case of severe respiratory impairment, very frail baseline condition or delirium occurrence.

Predictors of Helmet CPAP Failure in COVID-19 Pneumonia: A Prospective, Multicenter, and Observational Cohort Study.

Background: Continuous positive airway pressure (CPAP) can be beneficial in acute respiratory failure (ARF) due to coronavirus (COVID-19) pneumonia, but delaying endotracheal intubation (ETI) in nonresponders may increase mortality. We aimed at investigating the performance of composite respiratory indexes as possible predictors of CPAP failure in ARF due to COVID-19. Methods: This was a multicenter, prospective, observational, and cohort study conducted in the respiratory units of three University hospitals in Milan and in a secondary care hospital in Codogno (Italy), on consecutive adult patients with ARF due to COVID-19 pneumonia that underwent CPAP between March 2020 and March 2021. ETI transfer to the intensive care unit or death is defined CPAP failure. Predictors of CPAP failure were assessed before T0 and 1 hour after T1 CPAP initiation and included mROX index (ratio of PaO2/FiO2 to respiratory rate), alveolar-to-arterial (A-a) O2 gradient, and the HACOR (heart rate, acidosis, consciousness, oxygenation, and respiratory rate) score. Results: Three hundred and fifty four patients (mean age 64 years, 73% males) were included in the study; 136 (38.4%) satisfied criteria for CPAP failure. A-a O2 gradient, mROX, and HACOR scores were worse in patients who failed CPAP, both at T0 and T1 (p < 0.001 for all parameters). The HACOR score was associated with CPAP failure (odds ratio-OR-for every unit increase in HACOR = 1.361; 95%CI: 1.103-1.680; p=0.004; AUROC = 0.742; p < 0.001). CPAP failure was best predicted by a threshold of 4.50 (sensitivity = 53% and specificity = 87%). Conclusions: The HACOR score may be a reliable and early predictor of CPAP failure in patients treated for ARF in COVID-19 pneumonia.

Anti-Inflammatory Effects of Immunostimulation in Patients with COVID-19 Pneumonia.

BACKGROUND: The effects of immunomodulators in patients with Coronavirus Disease 2019 (COVID-19) pneumonia are still unknown. We investigated the cellular inflammatory and molecular changes in response to standard-of-care + pidotimod (PDT) and explored the possible association with blood biomarkers of disease severity. METHODS: Clinical characteristics and outcomes, neutrophil-to-lymphocyte ratio (NLR), plasma and cell supernatant chemokines, and gene expression patterns after SARS-CoV-2 and influenza (FLU) virus in vitro stimulation were assessed in 16 patients with mild-moderate COVID-19 pneumonia, treated with standard of care and PDT 800 mg twice daily (PDT group), and measured at admission, 7 (T1), and 12 (T2) days after therapy initiation. Clinical outcomes and NLR were compared with age-matched historical controls not exposed to PDT. RESULTS: Hospital stay, in-hospital mortality, and intubation rate did not differ between groups. At T1, NLR was 2.9 (1.7-4.6) in the PDT group and 5.5 (3.4-7.1) in controls (p = 0.037). In the PDT group, eotaxin and IL-4 plasma concentrations progressively increased (p < 0.05). Upon SARS-CoV-2 and FLU-specific stimulation, IFN-γ was upregulated (p < 0.05), while at genetic transcription level, Pathogen Recognition Receptors (TRLs) were upregulated, especially in FLU-stimulated conditions. CONCLUSIONS: Immunomodulation exerted by PDT and systemic corticosteroids may foster a restoration in the innate response to the viral infection. These results should be confirmed in larger RCTs.

Feasibility and Clinical Outcomes of a Step Up Noninvasive Respiratory Support Strategy in Patients with Severe COVID-19 Pneumonia.

The best noninvasive respiratory strategy in patients with Coronavirus Disease 2019 (COVID-19) pneumonia is still discussed. We aimed at assessing the rate of endotracheal intubation (ETI) in patients treated with continuous positive airway pressure (CPAP) and noninvasive ventilation (NIV) if CPAP failed. Secondary outcomes were in-hospital mortality and in-hospital length of stay (LOS). A retrospective, observational, multicenter study was conducted in intermediate-high dependency respiratory units of two Italian university hospitals. Consecutive patients with COVID-19 treated with CPAP were enrolled. Thoraco-abdominal asynchrony or hemodynamic instability led to ETI. Patients showing SpO2 ≤ 94%, respiratory rate ≥ 30 bpm or accessory muscle activation on CPAP received NIV. Respiratory distress and desaturation despite NIV eventually led to ETI. 156 patients were included. The overall rate of ETI was 30%, mortality 18% and median LOS 24 (17-32) days. Among patients that failed CPAP (n = 63), 28% were intubated, while the remaining 72% received NIV, of which 65% were intubated. Patients intubated after CPAP showed lower baseline PaO2/FiO2, lower lymphocyte counts and higher D-dimer values compared with patients intubated after CPAP + NIV. Mortality was 22% with CPAP + ETI, and 20% with CPAP + NIV + ETI. In the case of CPAP failure, a NIV trial appears feasible, does not deteriorate respiratory status and may reduce the need for ETI in COVID-19 patients.

PD-1 blockade counteracts post-COVID-19 immune abnormalities and stimulates the anti-SARS-CoV-2 immune response.

A substantial proportion of patients who have recovered from coronavirus disease-2019 (COVID-19) experience COVID-19-related symptoms even months after hospital discharge. We extensively immunologically characterized patients who recovered from COVID-19. In these patients, T cells were exhausted, with increased PD-1+ T cells, as compared with healthy controls. Plasma levels of IL-1ß, IL-1RA, and IL-8, among others, were also increased in patients who recovered from COVID-19. This altered immunophenotype was mirrored by a reduced ex vivo T cell response to both nonspecific and specific stimulation, revealing a dysfunctional status of T cells, including a poor response to SARS-CoV-2 antigens. Altered levels of plasma soluble PD-L1, as well as of PD1 promoter methylation and PD1-targeting miR-15-5p, in CD8+ T cells were also observed, suggesting abnormal function of the PD-1/PD-L1 immune checkpoint axis. Notably, ex vivo blockade of PD-1 nearly normalized the aforementioned immunophenotype and restored T cell function, reverting the observed post-COVID-19 immune abnormalities; indeed, we also noted an increased T cell-mediated response to SARS-CoV-2 peptides. Finally, in a neutralization assay, PD-1 blockade did not alter the ability of T cells to neutralize SARS-CoV-2 spike pseudotyped lentivirus infection. Immune checkpoint blockade ameliorates post-COVID-19 immune abnormalities and stimulates an anti-SARS-CoV-2 immune response.

Clinical Management of Adult Patients with COVID-19 Outside Intensive Care Units: Guidelines from the Italian Society of Anti-Infective Therapy (SITA) and the Italian Society of Pulmonology (SIP).

INTRODUCTION: The Italian Society of Anti-Infective Therapy (SITA) and the Italian Society of Pulmonology (SIP) constituted an expert panel for developing evidence-based guidance for the clinical management of adult patients with coronavirus disease 2019 (COVID-19) outside intensive care units. METHODS: Ten systematic literature searches were performed to answer ten different key questions. The retrieved evidence was graded according to the Grading of Recommendations Assessment, Development, and Evaluation methodology (GRADE). RESULTS AND CONCLUSION: The literature searches mostly assessed the available evidence on the management of COVID-19 patients in terms of antiviral, anticoagulant, anti-inflammatory, immunomodulatory, and continuous positive airway pressure (CPAP)/non-invasive ventilation (NIV) treatment. Most evidence was deemed as of low certainty, and in some cases, recommendations could not be developed according to the GRADE system (best practice recommendations were provided in similar situations). The use of neutralizing monoclonal antibodies may be considered for outpatients at risk of disease progression. For inpatients, favorable recommendations were provided for anticoagulant prophylaxis and systemic steroids administration, although with low certainty of evidence. Favorable recommendations, with very low/low certainty of evidence, were also provided for, in specific situations, remdesivir, alone or in combination with baricitinib, and tocilizumab. The presence of many best practice recommendations testified to the need for further investigations by means of randomized controlled trials, whenever possible, with some possible future research directions stemming from the results of the ten systematic reviews.

Enhanced platelet inhibition treatment improves hypoxemia in patients with severe Covid-19 and hypercoagulability. A case control, proof of concept study.

Patients affected by severe coronavirus induced disease-2019 (Covid-19) often experience hypoxemia due to alveolar involvement and endothelial dysfunction, which leads to the formation of micro thrombi in the pulmonary capillary vessels. Both hypoxemia and a prothrombotic diathesis have been associated with more severe disease and increased risk of death. To date, specific indications to treat this condition are lacking. This was a single center, investigator initiated, compassionate use, proof of concept, case control, phase IIb study (NCT04368377) conducted in the Intermediate Respiratory Care Unit of L. Sacco University Hospital in Milano, Italy. Our objective was to explore the effects of the administration of anti-platelet therapy on arterial oxygenation and clinical outcomes in patients with severe Covid-19 with hypercoagulability. We enrolled five consecutive patients with laboratory confirmed SARS-CoV-2 infection, severe respiratory failure requiring helmet continuous positive airway pressure (CPAP), bilateral pulmonary infiltrates and a pro-thrombotic state identified as a D-dimer > 3 times the upper limit of normal. Five patients matched for age, D-dimer value and SOFA score formed the control group. Beyond standard of care, treated patients received 25 µg/Kg/body weight tirofiban as bolus infusion, followed by a continuous infusion of 0.15 µg/Kg/body weight per minute for 48 hours. Before tirofiban, patients received acetylsalicylic acid 250 mg infusion and oral clopidogrel 300 mg; both were continued at a dose of 75 mg daily for 30 days. Fondaparinux2.5 mg/day sub-cutaneous was given for the duration of the hospital stay. All controls were receiving prophylactic or therapeutic dose heparin, according to local standard operating procedures. Treated patients consistently experienced a mean (SD) reduction in A-a O2 gradient of -32.6 mmHg (61.9, P = 0.154), -52.4 mmHg (59.4, P = 0.016) and -151.1 mmHg (56.6, P = 0.011; P = 0.047 vs. controls) at 24, 48 hours and 7 days after treatment. PaO2/FiO2 ratio increased by 52 mmHg (50, P = 0.172), 64 mmHg (47, P = 0.040) and 112 mmHg (51, P = 0.036) after 24, 48 hours and 7 days, respectively. All patients but one were successfully weaned from CPAP after 3 days. This was not true for the control group. No major adverse events were observed. Antiplatelet therapy might be effective in improving the ventilation/perfusion ratio in Covid-19 patients with severe respiratory failure. The effects might be sustained by the prevention and interference on forming clots in lung capillary vessels and by modulating megakaryocytes' function and platelet adhesion. Randomized clinical trials are urgently needed to confirm these results.

Characteristics, outcomes and global trends of respiratory support in patients hospitalized with COVID-19 pneumonia: a scoping review.

INTRODUCTION: To date, a shared international consensus on treatment of Coronavirus disease 2019 (COVID-19) with invasive or non-invasive respiratory support is lacking. Patients' management and outcomes, especially in severe and critical cases, can vary depending on regional standard operating procedures and local guidance. EVIDENCE ACQUISITION: Rapid review methodology was applied to include all the studies published on PubMed and Embase between December 15th, 2019 and February 28th, 2021, reporting in-hospital and respiratory support-related mortality in adult patients hospitalized with COVID-19 that underwent either continuous positive airway pressure (CPAP), non-invasive ventilation (NIV) or invasive mechanical ventilation (IMV). Only English language studies with ≥100 patients and reporting data on respiratory failure were included. Data on comorbidities, ventilatory parameters and hospital-related complications were registered. EVIDENCE SYNTHESIS: Fifty-two studies (287,359 patients; 57.5% males, mean age 64 years, range 24-98 years) from 17 different countries were included in the final analysis. 33.3% of patients were hospitalized in intensive care units. 44.2% had hypertension, 26.1% had diabetes, and 7.1% a chronic respiratory disease. 55% of patients underwent respiratory support (36% IMV, 62% NIV and 2% CPAP). Without considering a study with the highest number of patients treated with NIV (N.=96,729), prevalence of NIV and CPAP use was 12.5% and 13.5% respectively. Globally, invasive and non-invasive approaches were heterogeneously applied. In-hospital mortality was 33.7%, and IMV-related mortality was 72.6% (range: 4.3-99%). Specific mortality in patients treated with CPAP or NIV was available for 53% of studies, and was 29% (range: 7.2-100%). The median length of hospital stay was 13 days (range: 6-63). The most frequent hospital-related complication was acute kidney injury being reported in up to 55.7% of enrolled patients. CONCLUSIONS: Global employment of respiratory supports and related outcomes are very heterogeneous. The most frequent respiratory support in patients with COVID-19 pneumonia is IMV, while NIV and CPAP are less frequently and equally applied, the latter especially in Europe, while data on NIV/CPAP-related mortality is often under-reported. Integrated and comprehensive reporting is desirable and needed to construct evidence-based recommendations.

Mortality and clinical outcomes in patients with COVID-19 pneumonia treated with non-invasive respiratory support: A rapid review.

INTRODUCTION AND AIM: Non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) have been widely employed to treat acute respiratory failure secondary to COVID-19 pneumonia, but their role in terms of efficacy and safety are still debated. The aim of this review was to analyse mortality and intubation rates in COVID-19 patients treated with NIV/CPAP. METHODS: Rapid review methodology was applied to include all the studies published since December-2019 until November-2020 with available data on in-hospital mortality in COVID-19 patients treated with NIV or CPAP. RESULTS: 23 manuscripts were included (4776 patients, 66% males, 46% with hypertension). 46% of patients received non-invasive respiratory support, of which 48.4% with CPAP, 46% with NIV, and 4% with either CPAP or NIV. Non-invasive respiratory support failed in 47.7% of patients, of which 26.5% were intubated and 40.9% died. In-hospital mortality was higher in patients treated with NIV compared with CPAP (35.1% vs. 22.2%). Complications were under-reported, but mostly not related to CPAP/NIV treatment. CONCLUSION: CPAP and NIV appear equally and frequently applied in patients with COVID-19 pneumonia, but associated with high mortality. Robust evidence is urgently needed to confirm the clinical efficacy of non-invasive respiratory support in COVID-19-related ARDS.

How to Manage COVID-19 Vaccination in Immune-Mediated Inflammatory Diseases: An Expert Opinion by IMIDs Study Group.

Since March 2020, the outbreak of Sars-CoV-2 pandemic has changed medical practice and daily routine around the world. Huge efforts from pharmacological industries have led to the development of COVID-19 vaccines. In particular two mRNA vaccines, namely the BNT162b2 (Pfizer-BioNTech) and the mRNA-1273 (Moderna), and a viral-vectored vaccine, i.e. ChAdOx1 nCoV-19 (AstraZeneca), have recently been approved in Europe. Clinical trials on these vaccines have been published on the general population showing a high efficacy with minor adverse events. However, specific data about the efficacy and safety of these vaccines in patients with immune-mediated inflammatory diseases (IMIDs) are still lacking. Moreover, the limited availability of these vaccines requires prioritizing some vulnerable categories of patients compared to others. In this position paper, we propose the point of view about the management of COVID-19 vaccination from Italian experts on IMIDs and the identification of high-risk groups according to the different diseases and their chronic therapy.

Trends over Time of Lung Function and Radiological Abnormalities in COVID-19 Pneumonia: A Prospective, Observational, Cohort Study.

Radiological and functional sequelae of Coronavirus Disease 2019 (COVID-19) pneumonia are still poorly understood. This was a prospective, observational, physiological, cohort study on consecutive adult patients with COVID-19 pneumonia admitted in April-May 2020 in the high dependency respiratory unit of L. Sacco University Hospital in Milan (Italy). During hospitalization, patients underwent chest computed tomography (CT), blood gas analysis, spirometry, and lung diffusion capacity for carbon monoxide (DLco), which were repeated 6 weeks post-discharge. Chest CTs were individually read by two expert radiologists, that calculated the total severity score (TSS). Twenty patients completed the study (mean age 58.2 years, 70% males). During the acute phase, mean DLco, alveolar volume (VA), and vital capacity (VC) were 56.0 (16.3), 64.8 (14.0), and 71.7 (16.9) % predicted, respectively, and were inversely associated with PaO2/FiO2 ratio. Fifty percent of patients had a restrictive ventilatory pattern; mean TSS was 7.9 (4.0). At follow up, gas exchange parameters were normalized; consolidations persisted in 10% of cases, while DLco was <80% predicted in 65% of patients and was independently predicted by Log10D-dimer at admission (ß -18.675; 95%CI, -28.373--9.076; p = 0.001). In conclusion, functional abnormalities in COVID-19 pneumonia survivors can persist during follow up and are associated with the severity of the disease.

Characteristics and outcomes in hospitalized COVID-19 patients during the first 28 days of the spring and autumn pandemic waves in Milan: An observational prospective study.

BACKGROUND: The therapeutic approach to COVID-19 and healthcare system preparedness improved during 2020. We compared characteristics and outcomes of hospitalized COVID-19 patients during the first 28 days of the March and October pandemic waves in Milan, Italy. MATERIAL AND METHODS: A prospective, observational study enrolling adult patients hospitalized with COVID-19 pneumonia during March 7-April 4 (1st period) and October 15-November 12 (2nd period). During the 1st period hydroxychloroquine, lopinavir/ritonavir and therapeutic enoxaparin when thrombosis was confirmed were administered; systemic corticosteroids were given in case of severe pneumonia. During the 2nd period dexamethasone, methylprednisolone, remdesivir, thromboprophylaxis or anticoagulation were administered according to international recommendations. Patients with respiratory distress on oxygen masks initiated CPAP. Outcomes were: length of hospital stay, all-cause in-hospital mortality and need for intubation. RESULTS: We included 70 patients (75% males) during the 1st and 76 patients (51% males, p = 0.522) during the 2nd period. Prevalence of severe respiratory failure (30% vs. 12%, p = 0.006), and D-dimer >3000 FEU (34% vs. 15%, P = 0.012) were reduced during the 2nd period, while anticoagulation and corticosteroids were more frequently administered (both p < 0.01). Mortality and time to referral were also reduced (39.4% vs. 22.4%, p = 0.019 and 6 vs. 5 days, p = 0.014), while need for intubation didn't change. Hospitalization length was comparable, but the proportion of patients discharged home was higher during the 2nd period (28.2% vs. 55.4%, p = 0.001). CONCLUSIONS: Changing treatment paradigms and early referral might have reduced mortality in COVID-19 patients. The effects of specific therapeutic regimens needs further confirmation in future clinical studies.

Changes in quality of life and dyspnoea after hospitalization in COVID-19 patients discharged at home.

BACKGROUND: To date, the effects of COVID-19 pneumonia on health-related quality of life (HRQoL) and dyspnoea are unknown. METHODS: In a real-life observational study, 20 patients with COVID-19-related pneumonia received usual care plus erdosteine (300 mg twice daily) for 15 days after hospital discharge following local standard operating procedures. At discharge (T0) and on Day 15 (T1), participants completed the St George's Respiratory Questionnaire (SGRQ), the modified Medical Research Council (mMRC) scale of dyspnoea during daily activity, the BORG scale for dyspnoea during exertion, and Visual Analogue Scale (VAS) for dyspnoea at rest. Paired t-tests compared scores at T0 and T1. RESULTS: The mean (SD) SGRQ total score decreased from 25.5 (15.5) at T0 to 16.9 (13.2) at T1 (p<0.01); 65% of patients achieved a clinically important change of ≥4 points. SGRQ domain scores (symptoms, activity, and impact) were also significantly reduced (all p<0.01). The mean (SD) VAS score decreased from 1.6 (1.7) to 1.4 (2.5); p<0.01. The mean mMRC score decreased significantly (p=0.031) and 30% of patients achieved a clinically important change of ≥1 point. The mean (SD) Borg score increased from 12.8 (4.2) to 14.3 (2.4); p<0.01. CONCLUSION: The present proof of concept study is the first to report HRQoL in patients with COVID-19. During 15 days after hospital discharge, patients reported significant improvements in HRQoL and dyspnoea at rest and during daily activities.

Severity of respiratory failure at admission and in-hospital mortality in patients with COVID-19: a prospective observational multicentre study.

OBJECTIVES: COVID-19 causes lung parenchymal and endothelial damage that lead to hypoxic acute respiratory failure (hARF). The influence of hARF severity on patients' outcomes is still poorly understood. DESIGN: Observational, prospective, multicentre study. SETTING: Three academic hospitals in Milan (Italy) involving three respiratory high dependency units and three general wards. PARTICIPANTS: Consecutive adult hospitalised patients with a virologically confirmed diagnosis of COVID-19. Patients aged <18 years or unable to provide informed consent were excluded. INTERVENTIONS: Anthropometrical, clinical characteristics and blood biomarkers were assessed within the first 24 hours from admission. hARF was graded as follows: severe (partial pressure of oxygen to fraction of inspired oxygen ratio (PaO2/FiO2) <100 mm Hg); moderate (PaO2/FiO2 101-200 mm Hg); mild (PaO2/FiO2 201-300 mm Hg) and normal (PaO2/FiO2 >300 mm Hg). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the assessment of clinical characteristics and in-hospital mortality based on the severity of respiratory failure. Secondary outcomes were intubation rate and application of continuous positive airway pressure during hospital stay. RESULTS: 412 patients were enrolled (280 males, 68%). Median (IQR) age was 66 (55-76) years with a PaO2/FiO2 at admission of 262 (140-343) mm Hg. 50.2% had a cardiovascular disease. Prevalence of mild, moderate and severe hARF was 24.4%, 21.9% and 15.5%, respectively. In-hospital mortality proportionally increased with increasing impairment of gas exchange (p<0.001). The only independent risk factors for mortality were age ≥65 years (HR 3.41; 95% CI 2.00 to 5.78, p<0.0001), PaO2/FiO2 ratio ≤200 mm Hg (HR 3.57; 95% CI 2.20 to 5.77, p<0.0001) and respiratory failure at admission (HR 3.58; 95% CI 1.05 to 12.18, p=0.04). CONCLUSIONS: A moderate-to-severe impairment in PaO2/FiO2 was independently associated with a threefold increase in risk of in-hospital mortality. Severity of respiratory failure is useful to identify patients at higher risk of mortality. TRIAL REGISTRATION NUMBER: NCT04307459.