Changes in the Characteristics and Outcomes of COVID-19 Patients from the Early Pandemic to the Delta Variant Epidemic: A Nationwide Population-based Study.

The coronavirus disease 2019 (COVID-19) pandemic has dramatically changed because of virus mutations, vaccine dissemination, treatment development and policies, among other factors. These factors have a dynamic and complex effect on the characteristics and outcomes of patients. Therefore, there is an urgent need to understand those changes and update the evidence. We used a large-scale real-world data set of 937,758 patients with COVID-19 from a nationwide claims database that included outpatients and inpatients in Japan to investigate the changes in their characteristics, outcomes and risk factors for severity/mortality from the early pandemic to the delta variant-predominant waves. The severity of COVID-19 was defined according to the modified World Health Organization clinical-progression ordinal scale. With changing waves, mean patient age decreased, and proportion of patients with comorbidities decreased. The incidences of "severe COVID-19 or death (i.e. ≥severe COVID-19)" and "death" markedly declined (5.0% and 2.9%, wild-type-predominant; 4.6% and 2.2%, alpha variant-predominant and 1.4% and 0.4%, delta variant-predominant waves, respectively). Across the wave shift, risk factors for ≥severe COVID-19 and death, including older age, male, malignancy, congestive heart failure and chronic obstructive pulmonary disease, were largely consistent. The significance of some factors, such as liver disease, varied as per the wave. This study, one of the largest population-based studies on COVID-19, showed that patient characteristics and outcomes changed during the waves. Risk factors for severity/mortality were similar across all waves, but some factors were inconsistent. These data suggest that the clinical status of COVID-19 will change further with the coming epidemic wave.

Pathological Roles of Pulmonary Cells in Acute Lung Injury: Lessons from Clinical Practice.

Interstitial lung diseases (ILD) are relatively rare and sometimes become life threatening. In particular, rapidly progressive ILD, which frequently presents as acute lung injury (ALI) on lung histopathology, shows poor prognosis if proper and immediate treatments are not initiated. These devastating conditions include acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF), clinically amyopathic dermatomyositis (CADM), epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-induced lung injury, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection named coronavirus disease 2019 (COVID-19). In this review, clinical information, physical findings, laboratory examinations, and findings on lung high-resolution computed tomography and lung histopathology are presented, focusing on majorly damaged cells in each disease. Furthermore, treatments that should be immediately initiated in clinical practice for each disease are illustrated to save patients with these diseases.

Clinical practice of high-flow nasal cannula therapy in COVID-19 pandemic era: a cross-sectional survey of respiratory physicians.

BACKGROUND: Despite the rapid widespread use of a high-flow nasal cannula (HFNC) during the COVID-19 pandemic, its indications and appropriate use as perceived by physicians remain poorly known. METHODS: In September 2021, we sent a questionnaire to each respiratory physician from 15 institutions in Shizuoka prefecture, Japan. In this survey, we compared the perceptions of HFNC indications and interventions during implementation to those of non-invasive ventilation (NIV) and invasive mechanical ventilation (IMV). Furthermore, this study examined concerns about SARS-CoV-2 infection spread and psychological distress experienced among respondents. RESULTS: Of the 140 respiratory physicians contacted, 87 (62.1%) completed the survey. The results indicate that 96.5% of the respondents agreed with the indication of HFNC for COVID-19, whereas only 13.7% agreed with NIV. The physicians reported that patients with HFNC had a lower frequency of sustained sedation, physical restraint, and implementation in the ICU than that of patients with NIV and IMV. The HFNC was introduced as a respiratory modality following conventional oxygen therapy (COT) in patients with COVID-19, regardless of full or do-not-intubate codes. Additionally, they reported that patients with COVID-19 switched from COT to HFNC significantly earlier than those without COVID-19. Simultaneously, this survey revealed persistent concerns of SARS-CoV-2 infection spread and psychological distress (47.1% and 53.3%, respectively) among respiratory physicians during HFNC use. CONCLUSION: Clinically, HFNC is considered useful for COVID-19 patients by most respiratory physicians. However, HFNC remains a concern for COVID-19 spread and psychological distress among several respiratory physicians, indicating the need for urgent action.

Transient leukocytopenia following combination therapy for COVID-19.

BACKGROUND: Combination therapy with dexamethasone, remdesivir, and baricitinib has become a promising treatment for moderate or severe COVID-19; however, we have observed transient leukocytopenia in COVID-19 patients who received combination therapy. METHODS: Twelve consecutive COVID-19 patients treated with combination therapy were included in this retrospective analysis. Blood cell counts collected at the following three time points were analyzed: before the start of therapy (period 1), within 24 h of starting therapy (period 2), and within 48 h of period 2 (period 3). RESULTS: The leukocyte count significantly decreased in period 2 compared to period 1 and then significantly increased in period 3 without withdrawal of baricitinib. The neutrophil count transiently decreased in period 2 and recovered in period 3. CONCLUSIONS: Clinicians should be aware of transient leukocytopenia in patients with COVID-19 during the early phase of combination therapy.