Risk factors for severity on admission and the disease progression during hospitalisation in a large cohort of patients with COVID-19 in Japan

Development and Validation of Claims-based Algorithms for Identifying Hospitalized Patients With COVID-19 and Their Severity in 2020 and 2021

BACKGROUND

This study aimed to develop and validate claims-based algorithms for identifying hospitalized patients with coronavirus disease 2019 (COVID-19) and disease severity.

METHODS

We used claims data including all patients at the National Center for Global and Medicine Hospital between January 1, 2020, and December 31, 2021. The claims-based algorithms for three statuses with COVID-19 (hospitalizations, moderate or higher status, and severe status) were developed using diagnosis codes (International Classification of Diseases, 10th revision code: U07.1, B34.2) and relevant medical procedure code. True cases were determined using the COVID-19 inpatient registry and electronic health records. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each algorithm at 6-month intervals.

RESULTS

Of the 75,711 total patients, the number of true cases was 1,192 for hospitalizations, 622 for moderate or higher status, and 55 for severe status. The diagnosis code-only algorithm for hospitalization had sensitivities 90.4% to 94.9% and PPVs 9.3% to 19.4%. Among the algorithms consisting of both diagnosis codes and procedure codes, high sensitivity and PPV were observed during the following periods: 93.9% and 97.1% for hospitalization (January-June 2021), 90.4% and 87.5% for moderate or higher status (July-December 2021), and 92.3% and 85.7% for severe status (July-December 2020), respectively. Almost all algorithms had specificities and NPVs of approximately 99%.

CONCLUSION

The diagnosis code-only algorithm for COVID-19 hospitalization showed low validity throughout the study period. The algorithms for hospitalizations, moderate or higher status, and severe status with COVID-19, consisting of both diagnosis codes and procedure codes, showed high validity in some periods.

90-Day outcomes in patients with severe COVID-19 pneumonia treated with invasive mechanical ventilation

BACKGROUND

There are few reports detailing the prognostic factors of severe COVID-19 pneumonia requiring invasive ventilation. We investigated the long-term prognosis and evaluated which factors influenced outcomes in these patients.

METHODS

Data was reviewed from severe adult COVID-19 cases admitted to our hospital and treated with mechanical ventilation between February 1, 2020, and October 30, 2021. On admission to our hospital, comorbidities and laboratory findings were collected from clinical records. Prognostic information for 90 days after diagnosis was also obtained from hospitals where patients were transferred after their conditions stabilized.

RESULTS

Prognostic information was obtained in 133 patients, of which 106 were males (79.7 %). Of the 133 patients, 67 were discharged (51.5 %), 21 continued inpatient care (15.8 %), and 45 died (33.8 %). Age, Charlson Risk Index, and the number of patients on hemodialysis were significantly higher in the deceased group. There were no differences in therapeutic interventions between survivors and those who died except for a higher rate of muscle relaxant and vasopressor usage in the deceased group. Laboratory findings on admission showed significantly higher levels of BUN, creatinine, and serum Krebs von den Lungen 6 (KL-6), and significantly lower platelet counts, hemoglobin, and alanine aminotransferase in those who died. Multivariate analysis revealed that age, hemodialysis, lower platelet counts, and higher KL-6 were independent predictors for 90-day mortality.

CONCLUSIONS

Older age, hemodialysis, lower platelet counts and high KL-6 on admission were identified as independent predictors of 90-day mortality in patients with respiratory failure due to severe COVID-19 under invasive mechanical ventilation.

Clinical outcomes in patients with mild to moderate coronavirus disease 2019 treated with monoclonal antibody therapy versus an untreated control cohort

BACKGROUND

Monoclonal antibody therapy (MAT) received Food and Drug Administration (FDA) Emergency Use Authorization (EUA) for mild to moderate COVID-19 treatment in adults at a high-risk for progression to severe disease in November 2020. This study assessed the impact of MAT on clinical outcomes.

METHODS

We conducted a single-center, retrospective study comparing 30-day COVID-19-related emergency department (ED) visits, admissions, and mortality in patients receiving MAT (bamlanivimab, bamlanivimab-etesevimab, or casirivimab-imdevimab) between 16 November 2020 and 19 June 2021, compared to a control group of high-risk adults diagnosed with mild to moderate COVID-19 prior to MAT availability between 16 May 2020 and 15 November 2020. Statistical analysis used logistic regression analysis with backward selection to determine the odds ratios and 95% confidence interval evaluating the relationship between clinical characteristics and outcomes.

RESULTS

1187 patients who received MAT were compared to 1103 patients not treated with MAT. Multivariable regression model adjusted for possible confounders showed patients who received MAT had lower rates of ED visits (3.2% vs 7.4%, OR = 0.46, 95% CI = 0.31-0.70, p < .001) and hospital admissions (4.3% vs 7.8%, OR = 0.42, 95% CI = 0.29-0.62, p < .001) compared to the control group. After adjusting for confounders, MAT was associated with decreased mortality (OR = 0.36, p = .035). In the MAT group, those treated within 2 days of COVID-19 diagnosis had lower mortality than those treated more than 2 days post-diagnosis (unadjusted OR = 0.152, 95% CI = 0.031-0.734, p = .019).

CONCLUSIONS

Individuals treated with MAT had lower rates of 30-day COVID-19-related ED visits and hospital admissions compared to those not receiving MAT. Early MAT resulted in lower 30-day mortality compared to receipt >2 days post COVID-19 diagnosis.

Impact of Diabetes Mellitus On In-Hospital Mortality of COVID-19 Patients in Japan Since COVID-19 Became a Common Infectious Disease

AIM

The number of severe cases of coronavirus disease 2019 (COVID-19) has been decreasing since the emergence of the Omicron variant at the end of 2021. COVID-19 has become a common infectious disease in Japan and was downgraded to a category five infectious disease on May 8, 2023. This study aimed to compare the impact of diabetes mellitus on in-hospital mortality in COVID-19 patients since COVID-19 became a common infectious disease.

PATIENTS AND METHODS

We conducted a retrospective observational study using data from an advanced critical care center in Osaka, Japan. The study included 1,381 patients of COVID-19 admitted to the center between March 1, 2020, and May 7, 2023, before COVID-19 became a category five infectious disease in Japan. Individuals younger than 18 years and pregnant women were excluded. We divided the patients into two groups: pre- and post-Omicron epidemic groups. The primary endpoint of the study was the in-hospital mortality, and the prognostic impact of diabetes mellitus was compared between the groups.

RESULTS

The Kaplan-Meier curve showed a significantly lower rate of in-hospital mortality in the post-Omicron epidemic group than in the pre-Omicron epidemic group. The hazard ratio (HR) was 1.83 (95% CI, 1.36-2.50; p < 0.0001). Patients with diabetes mellitus had higher in-hospital mortality in both the pre- and post-Omicron epidemic groups; their HRs were 1.39 (95% CI, 1.21-1.59; p < 0.0001) and 1.45 (95% CI, 1.15-1.83; p = 0.0012), respectively. Diabetes mellitus had no significant interaction effect on the association between the post-Omicron epidemic and in-hospital mortality (p for interaction = 0.2154).

CONCLUSION

Diabetes mellitus may continue contributing to COVID-19 in-hospital mortality in the future, as the Omicron sub-strain may still be prevalent.

Factors Related to Mortality in Patients with COVID-19 during the Early Phase of the Pandemic in Japan: An Observational Study Using the Osaka Prefectural Novel Coronavirus Response Status Management System

Introduction

Elucidating the epidemiological picture in the early phase of a pandemic is crucial to strengthening preparedness and public health responses to future emerging infectious diseases. Using data from the "Osaka Prefectural Novel Coronavirus Response Status Management System," we evaluated factors associated with mortality among patients with novel coronavirus disease 2019 (COVID-19) in Osaka Prefecture, Japan.

Methods

The study periods were from January 29 to June 13, 2020 (first surge), from June 14 to October 9, 2020 (second surge), and from October 10 to December 24, 2020 (up to the middle of the third surge). The odds ratios (ORs) and 95% confidence intervals (95% CIs) for mortality were calculated using logistic regression models.

Results

Of the 14,864 patients with COVID-19 (8,207 men, 6,657 women) registered, 297 (2%) died. The ORs for mortality were significantly higher in men (OR = 2.00, 95% CI = 1.54-2.60) than in women, in 70- to 79-year-olds (OR = 25.4, 95% CI = 16.8-38.2) and ≥80-year-olds (OR = 78.1, 95% CI = 53.3-114) than in 0- to 69-year-olds (P for trend < 0.001), and in those with underlying diseases (OR = 1.74, 95% CI = 1.34-2.27) than in those without. The ORs for the second surge (OR = 0.42, 95% CI = 0.31-0.57) and third surge (OR = 0.41, 95% CI = 0.29-0.58) decreased compared with the first surge. Detailed evaluation of underlying diseases by time period showed that "Diseases of the blood and blood-forming organs and certain disorders involving immune mechanisms," "Endocrine, nutritional, and metabolic diseases," "Diseases of the genitourinary system," and "Diseases of the respiratory system" were associated with increased risk of mortality.

Conclusions

Among those affected early in the COVID-19 epidemic, male sex, older age, first-surge infection, and underlying medical conditions were significantly associated with mortality. Our findings are expected to provide a useful reference for future countermeasures in the early stages of pandemics involving unknown emerging infectious diseases.

Prediction of COVID-19 Severity at Delivery after Asymptomatic or Mild COVID-19 during Pregnancy

OBJECTIVE

 This study aimed to develop a prediction model that estimates the probability that a pregnant person who has had asymptomatic or mild coronavirus disease 2019 (COVID-19) prior to delivery admission will progress in severity to moderate, severe, or critical COVID-19.

STUDY DESIGN

 This was a secondary analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients who delivered from March through December 2020 at hospitals across the United States. Those eligible for this analysis presented for delivery with a current or previous asymptomatic or mild SARS-CoV-2 infection. The primary outcome was moderate, severe, or critical COVID-19 during the delivery admission through 42 days postpartum. The prediction model was developed and internally validated using stratified cross-validation with stepwise backward elimination, incorporating only variables that were known on the day of hospital admission.

RESULTS

 Of the 2,818 patients included, 26 (0.9%; 95% confidence interval [CI], 0.6-1.3%) developed moderate-severe-critical COVID-19 during the study period. Variables in the prediction model were gestational age at delivery admission (adjusted odds ratio [aOR], 1.15; 95% CI, 1.08-1.22 per 1-week decrease), a hypertensive disorder in a prior pregnancy (aOR 3.05; 95% CI, 1.25-7.46), and systolic blood pressure at admission (aOR, 1.04; 95% CI, 1.02-1.05 per mm Hg increase). This model yielded an area under the receiver operating characteristic curve of 0.82 (95% CI, 0.72-0.91).

CONCLUSION

 Among individuals presenting for delivery who had asymptomatic-mild COVID-19, gestational age at delivery admission, a hypertensive disorder in a prior pregnancy, and systolic blood pressure at admission were predictive of delivering with moderate, severe, or critical COVID-19. This prediction model may be a useful tool to optimize resources for SARS-CoV-2-infected pregnant individuals admitted for delivery.

KEY POINTS

· Three factors were associated with delivery with more severe COVID-19.. · The developed model yielded an area under the receiver operating characteristic curve of 0.82 and model fit was good.. · The model may be useful tool for SARS-CoV-2 infected pregnancies admitted for delivery..

Association of excess visceral fat and severe illness in hospitalized COVID-19 patients in Japan: a retrospective cohort study

BACKGROUND/OBJECTIVES

Obesity, defined by body mass index (BMI), is a well-known risk factor for the severity of coronavirus disease 2019 (COVID-19). Adipose tissue distribution has also been implicated as an important factor in the body's response to infection, and excess visceral fat (VF), which is prevalent in Japanese, may contribute significantly to the severity. Therefore, this study aimed to evaluate the association of obesity and VF with COVID-19 severe illness in Japan.

SUBJECTS/METHODS

This retrospective cohort study involved 550 COVID-19 patients admitted to a tertiary care hospital with BMI and body composition data, including VF. The primary endpoint was severe illness, including death, due to COVID-19 during hospitalization. Logistic regression analysis was applied to examine the quartiles of BMI and VF on severe illness after adjusting for covariates such as age, sex, subcutaneous fat, paraspinal muscle radiodensity, and comorbidities affecting VF (COPD, cancer within 5 years, immunosuppressive agent use).

RESULTS

The median age was 56.0 years; 71.8% were males. During hospitalization, 82 (14.9%) experienced COVID-19 severe illness. In the multivariate logistic regression analysis, Q4 of BMI was not significantly associated with severe illness compared to Q1 of BMI (OR 1.03; 95% CI 0.37-2.86; p = 0.95). Conversely, Q3 and Q4 of VF showed a higher risk for severe illness compared to Q1 of VF (OR 2.68; 95% CI 1.01-7.11; p = 0.04, OR 3.66; 95% CI 1.30-10.26; p = 0.01, respectively). Stratified analysis by BMI and adjusted for covariates showed the positive association of VF with severe illness only in the BMI < 25 kg/m2 group.

CONCLUSIONS

High BMI was not an independent risk factor for COVID-19 severe illness in hospitalized patients in Japan, whereas excess VF significantly influenced severe illness, especially in patients with a BMI < 25 kg/m2.

Clinical features in patients with COVID-19 treated with biologics for severe asthma

Background

Few studies have reported the clinical features of patients with coronavirus disease 2019 (COVID-19) who were treated with biologics for severe asthma (SA).

Objective

We sought to elucidate the clinical features and mutual interaction between COVID-19 and SA in terms of disease severity during the Omicron epidemic.

Methods

A retrospective study among patients with SA who received any biologic therapy from January 2022 to February 2023 at Jikei University Hospital (Tokyo, Japan) was performed.

Results

Among 99 patients with SA, 22 women and 6 men suffered from COVID-19, and 1 woman was reinfected. The severity of COVID-19 was mild in 26 cases and moderate in 3 cases. The number of vaccinations among patients with mild COVID-19 was significantly higher than that among patients with moderate COVID-19 (3.0 ± 1.4 vs 1.0 ± 1.0; P = .03). Asthmatic exacerbations were mild in 9 cases and moderate in 7 cases. The severity of asthmatic exacerbations was significantly associated with the Asthma Control Test score at baseline (no/mild/moderate exacerbation = 23.0 ± 2.3/18.1 ± 5.3/15.0 ± 4.3; P = .004; Kruskal-Wallis test). By means of a multivariate logistic regression analysis, a lower number of vaccinations was a significant risk factor for COVID-19 progression (odds ratio, 0.64; 95% CI, 0.46-0.91; P = .006).

Conclusions

During the Omicron epidemic, the onset and severity of COVID-19 were related to the number of vaccinations, and the severity of asthmatic exacerbations caused by COVID-19 was associated with the Asthma Control Test score at baseline and the number of vaccinations but not with the use of biologics.

Vital Signs as Predictors of Oxygen Requirements in COVID-19 Outpatients: The Development of a Streamlined Risk Score

BACKGROUND

With COVID-19 becoming a common disease, primary care facilities such as clinics are required to efficiently triage patients at high risk of severe illness within the constraints of limited medical resources. However, existing COVID-19 severity risk scores require detailed medical history assessments, such as evaluating the severity of pneumonia via chest CT and accounting for past and comorbid conditions. Therefore, they may not be suitable for practical use in clinical settings with limited medical resources, including personnel and equipment.

PURPOSE

 The goal is to identify key variables that predict the need for oxygen therapy in COVID-19 patients and develop a simplified clinical risk score based solely on vital signs to predict oxygen requirements.

PATIENTS AND METHODS

A retrospective observational study of 584 outpatients with COVID-19 confirmed by polymerase chain reaction test visited Sasebo Chuo Hospital between April 28, 2022, and August 18, 2022. Analyses were conducted after adjustment for background factors of age and sex with propensity score matching. We used the Fisher test for nominal variables and the Kruskal-Wallis test for continuous variables.

RESULTS

After adjusting for age and sex, several factors significantly correlated with the need for oxygen within seven days including body temperature (p < 0.001), respiratory rate (p = 0.007), SpO2 (p < 0.001), and the detection of pneumonia on CT scans (p = 0.032). The area under the receiver-operating characteristic curve for the risk score based on these vital signs and CT was 0.947 (95% confidence interval: 0.911-0.982). The risk score based solely on vital signs was 0.937 (0.900-0.974), demonstrating the ability to predict oxygen administration with no significant differences.

CONCLUSIONS

Body temperature, advanced age, increased respiratory rate, decreased SpO2, and the presence of pneumonia on CT scans were significant predictors of oxygen need within seven days among the study participants. The risk score, based solely on vital signs, effectively and simply assesses the likelihood of requiring oxygen therapy within seven days with high accuracy. The risk score, which utilizes only age and vital signs and does not require a detailed patient history or CT scans, could streamline hospital referral processes for admissions.

Assessing antiviral treatment efficacy and risk factors for severe COVID-19 in kidney transplant recipients during the Omicron subvariant-dominant period: a retrospective study

BACKGROUND

Kidney transplant recipients (KTRs) are at risk of severe coronavirus disease 2019 (COVID-19), and even now that Omicron subvariants have become dominant, cases of severe disease are certain to occur. The aims of this retrospective study were to evaluate the efficacy of antiviral treatment for COVID-19 and to identify risk factors for severe disease in KTRs during Omicron subvariant-dominant periods.

METHODS

A total of 65 KTRs diagnosed with COVID-19 who received antiviral treatment between July 2022 and September 2023 were analyzed. Mild cases received oral molnupiravir (MP) as outpatient therapy, while moderate or worse cases received intravenous remdesivir (RDV) as inpatient therapy. In principle, mycophenolate mofetil was withdrawn and switched to everolimus. We investigated the efficacy of antiviral treatment and compared the clinical parameters of mild/moderate and severe/critical cases to identify risk factors for severe COVID-19.

RESULTS

Among 65 cases, 49 were mild, 6 were moderate, 9 were severe, and 1 was of critical severity. MP was administered to 57 cases; 49 (86%) improved and 8 (14%) progressed. RDV was administered to 16 cases; 14 (87%) improved and 2 (13%) progressed. Seventeen (26%) cases required hospitalization, and none died. Comparisons of the severe/critical group (n = 10) with the mild/moderate group (n = 55) demonstrated that the severe/critical group had a significantly higher median age (64 vs. 53 years, respectively; p = 0.0252), prevalence of diabetes (70% vs. 22%, respectively; p = 0.0047) and overweight/obesity (40% vs. 11%, respectively; p = 0.0393), as well as a significantly longer median time from symptom onset to initial antiviral therapy (3 days vs. 1 day, respectively; p = 0.0026). Multivariate analysis showed that a longer time from symptom onset to initial antiviral treatment was an independent risk factor for severe COVID-19 (p = 0.0196, odds ratio 1.625, 95% confidence interval 1.081-2.441).

CONCLUSION

These findings suggest that a longer time from symptom onset to initial antiviral treatment is associated with a higher risk of severe COVID-19 in KTRs. Initiating antiviral treatment as early as possible is crucial for preventing severe outcomes; this represents a valuable insight into COVID-19 management in KTRs.

Effectiveness of remdesivir-based therapy for moderate COVID-19: comparison of Omicron and other variant phases

Remdesivir is an antiviral drug for the treatment of coronavirus disease 2019 (COVID-19), and the sustained antiviral activity against Omicron variants of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been reported. In this single-center retrospective study, we first compared the clinical effectiveness of remdesivir-based therapy between Omicron and other variant phases of moderate COVID-19 in a real-world setting. Between Dec 2020 and July 2022, a total of 406 patients with COVID-19 pneumonia were treated with remdesivir-based therapy on admission. The oxygen deterioration rate after initiation of treatment significantly decreased in the Omicron variant phase compared to the alpha and delta variant phases. In an adjusted multivariate Cox proportional hazards model, Omicron variant phase was significantly associated with delayed oxygen deterioration and early recovery from hypoxia. These favorable outcomes during the Omicron variant phase, compared to previous variant phases, might be due to the attenuation and the popularization of vaccination.

Depressive symptoms associated with infection prevention measures and daily lifestyle habit characteristics among Japanese community-dwelling older adults during the COVID-19 pandemic

AIM

This study aimed to clarify the relationship between depressive symptoms and infection prevention measures and daily lifestyle habits during the coronavirus disease 2019 pandemic among community-dwelling Japanese older adults.

METHODS

This cross-sectional study was conducted on older residents (age ≥65 years) living in the Tama area of Tokyo and Sapporo, Hokkaido, in 2021. A self-administered questionnaire survey was conducted to collect data on demographics, the impact of the pandemic on physical condition, and depressive symptoms, infection prevention measures, and daily lifestyle habits during the pandemic. The Geriatric Depression Scale was used to assess depressive symptoms.

RESULTS

In total, 554 respondents were included in the analysis. The results of multiple logistic regression analyses revealed that refraining from going out and visiting medical institutions were associated with depressive symptoms. Furthermore, those who went out almost every day were less likely to have depressive symptoms than the others, those who exercised almost every day were less likely to have depressive symptoms than were those who almost never exercised, and those who slept 6-7 h were less likely to have depressive symptoms than were those who slept ≤5 h.

CONCLUSIONS

The findings of the present study suggest the necessity of having a place where older adults with physical and lifestyle concerns can consult with healthcare providers in a location other than a medical institution, even during infectious disease outbreaks. In addition, increasing the frequencies of going out and independent exercise and sleeping 6-7 h may help prevent depression among older adults.

Factors associated with the worsening of COVID-19 symptoms among cohorts in community- or home-isolation care in southern Thailand

Introduction

This study aimed to investigate factors associated with time-to-referral due to worsening symptoms in patients with laboratory-confirmed COVID-19 in southern Thailand. While underlying diseases have been evaluated to assess COVID-19 severity, the influence of vaccinations and treatments is also crucial.

Methods

A cohort of 8,638 patients quarantined in home or community isolation with laboratory-confirmed COVID-19 was analyzed. Survival analysis and the Cox proportional hazard ratio were employed to assess factors influencing time-toreferral.

Results

Age ≥ 60 years, neurologic disorders, cardiovascular disease, and human immunodeficiency virus infection were identified as significant risk factors for severe COVID-19 referral. Patients who received full- or booster-dose vaccinations had a lower risk of experiencing severe symptoms compared to unvaccinated patients. Notably, individuals vaccinated during the Omicron-dominant period had a substantially lower time-to-referral than those unvaccinated during the Delta-dominant period. Moreover, patients vaccinated between 1 and 6 months prior to infection had a significantly lower risk of time-to-referral than the reference group.

Discussion

These findings demonstrate early intervention in high-risk COVID-19 patients and the importance of vaccination efficacy to reduce symptom severity. The study provides valuable insights for guiding future epidemic management strategies and optimising patient care during infectious disease outbreaks.

The relation between proteinuria and the severity of COVID-19

BACKGROUND

The association between proteinuria, which is also an indicator of chronic kidney disease (CKD), and coronavirus disease 2019 (COVID-19) severity is unclear.

METHODS

We selected 342 hospitalized patients with COVID-19 diagnosed via polymerase chain reaction testing between February 2020 and October 2022 and who had at least one urinalysis 14-365 days before admission.

RESULTS

Proteinuria before admission was associated neither with oxygen administration nor developing pneumonia in multivariate analysis (odds ratio [OR] 1.03; 95% confidence interval (CI) 0.44-2.40, p = 0.95 and OR 1.01; 95% CI 0.47-2.17, p = 0.98, respectively). Proteinuria on admission was associated both with oxygen administration and developing pneumonia in multivariate analysis (OR 3.29; 95% CI 1.37-7.88, p < 0.01 and OR 3.81; 95% CI 1.68-8.62, p < 0.01, respectively). The percentage of patients with proteinuria on admission was significantly higher than those before admission (37.4% vs. 17.8%; p < 0.01). In the subgroup analysis, proteinuria on admission among patients with eGFR ≥ 60 mL/min/1.73 m2 was associated with both oxygen administration and developing pneumonia (OR 4.86; 95% CI 1.22-19.38, p = 0.03, OR 3.65; 95% CI 1.06-12.58, p = 0.04, respectively). In contrast, proteinuria on admission among patients with eGFR < 60 mL/min/1.73 m2 was associated with developing pneumonia (OR 6.45; 95%CI 1.78-23.35, p = 0.01), not with oxygen administration (OR 3.28; 95% CI 0.92-11.72, p = 0.07).

CONCLUSIONS

Although underlying proteinuria before admission was not associated with COVID-19 severity, proteinuria on admission was associated with oxygen demand and developing pneumonia.

Prognostic significance of hypertension history and blood pressure on admission in Japanese patients with coronavirus disease 2019: integrative analysis from the Japan COVID-19 Task Force

The effect of preexisting hypertension on coronavirus disease 2019 (COVID-19) prognosis remains controversial. Additionally, no studies have compared the association between blood pressure (BP) indices on admission and COVID-19 outcomes using preexisting hypertension status. Therefore, this study aimed to investigate the association between preexisting hypertension and COVID-19 outcomes in Japanese patients with COVID-19 and assess the impact of BP indices on admission on clinical outcomes in patients with and without preexisting hypertension. Preexisting hypertension presence was confirmed based on the patient's clinical history. Critical outcomes were defined as high-flow oxygen use, non-invasive and invasive positive-pressure ventilation, extracorporeal membrane oxygenation, or death during hospitalization. Preexisting hypertension was observed in 64.6% of the patients. Multivariable logistic regression analysis of severe COVID-19 risk factors indicated that preexisting hypertension was independently associated with critical outcomes [adjusted odds ratio (OR): 1.35; 95% confidence interval (CI): 1.05-1.73]. Low or high BP and high pulse pressure on admission were associated with critical outcomes in patients without preexisting hypertension [OR for systolic BP < 100 mmHg: 2.13, 95% CI: 1.21-3.75; OR for high BP stage 2 (160-179 systolic and/or 100-109 mmHg diastolic BP): 2.13, 95% CI: 1.27-3.58; OR for pulse pressure ≥60 mmHg: 1.68, 95% CI: 1.14-2.48]. Preexisting hypertension is a risk factor for critical outcomes in Japanese patients with COVID-19. BP indices are useful biomarkers for predicting COVID-19 outcomes, particularly in patients without preexisting hypertension. Thus, hypertension history, systolic BP, and pulse pressure should be assessed to predict severe COVID-19 outcomes.

Activity of Daily Living and Walking Ability of Patients with Severe COVID-19 at Discharge from an Acute Care Hospital

Objectives

The effectiveness of acute rehabilitation treatment for severe coronavirus disease 2019 (COVID-19) has not yet been established. This study examined the efficacy of treatment provided to patients with severe COVID-19 in an acute care facility.

Methods

A total of 98 patients with severe COVID-19 requiring inpatient management in our intensive care unit (ICU) were included between December 2020 and October 2021. They were divided into two groups: those who received physiotherapy (PT group; n=44) and those who did not receive physiotherapy (non-PT group; n=54). Their backgrounds, clinical characteristics, and activities of daily life (ADL) at discharge were compared to examine factors that influenced the need for physiotherapy (PT). We also evaluated the effect of PT on ADL by comparing the Barthel Index (BI) before PT and at discharge.

Results

The PT group patients were significantly older, had longer hospital and ICU stays, and used invasive mechanical ventilators (IMV) more frequently than those in the non-PT group. More patients in the non-PT group were able to walk at discharge than in the PT group. The PT group patients showed significant improvement in BI and ADL at discharge when compared with BI at the start of PT, regardless of whether an IMV was used.

Conclusions

Older patients with severe COVID-19 with prolonged hospitalization or ICU stay or on an IMV are prone to a decline in ADL and may need to be considered for early PT.

Appropriate Endotracheal Tube Position for Percutaneous Dilatational Tracheostomy: A Single-Center Observational Study

Aim This study aimed to investigate the appropriate endotracheal tube (ETT) position during percutaneous dilatational tracheostomy (PDT). Methods This single-center observational study included hospitalized patients who underwent surgical tracheostomy (ST) between August 2021 and October 2022. During ST, the trachea was opened, and the ETT was pulled out visually. It stopped when the ETT was no longer visible, and the tracheostomy tube was placed in the trachea. The ETT position was measured by considering the ETT position during ST to be the appropriate position during PDT. The correlation between the measured ETT position and patient characteristics was evaluated. A prediction equation for the ETT position was derived from the derivation group, and validation of the prediction equation was evaluated by the validation group. Results Forty-six and 15 patients were in the derivation and validation groups, respectively. Weight, duration of intubation, and in-hospital mortality were significantly different between the two groups. The measured ETT position correlated with body height (r=0.60, p<0.001) and sex (r=0.45, p=0.002), while the ETT position before ST showed a weak correlation (r=0.34, p=0.020). The predicted and measured values in the validation group correlated with each other (r=0.58, p=0.024). Conclusion The appropriate ETT position for PDT correlates with body height, and the equation "body height×0.112-0.323 cm" was derived. This predictive equation may be useful as a guide for ETT positioning during PDT puncture.

Obesity, overweight, and severe prognosis in COVID-19 patients in Japan

INTRODUCTION

Obesity (i.e., body mass index [BMI] of 30 kg/m2 or more) is one of the risk factors for severe COVID-19, but the findings may not be directly applicable to Asians, who have a different cutoff point for defining obesity. We thus examined the association between obesity/overweight (BMI of 25 kg/m2 or more and less than 30 kg/m2) and the risk of COVID-19 severity.

METHODS

The study population included COVID-19 patients who had been enrolled in the registry of the Okayama City Public Health Center in Okayama, Japan, between March 2020 and June 2022. We included 27 820 patients who had information on BMI and prognosis, and we conducted Poisson regression analysis with robust error variance to estimate risk ratios (RRs) with 95% confidence intervals (CIs) for severe outcomes.

RESULTS

Obesity and overweight were associated with the increased risk of severe COVID-19 in all age categories. The RRs (95% CI) for COVID-19 induced respiratory failure compared to the normal weight category were 1.57 (1.31-1.88) for overweight and 2.45 (1.90-3.15) for obesity.

CONCLUSIONS

Both obesity and overweight were associated with increased risk of severe COVID-19. This study suggests the importance of the overweight category to predict the risk of severe COVID-19 in Asians.

Prediction of oxygen supplementation by a deep-learning model integrating clinical parameters and chest CT images in COVID-19

PURPOSE

As of March 2023, the number of patients with COVID-19 worldwide is declining, but the early diagnosis of patients requiring inpatient treatment and the appropriate allocation of limited healthcare resources remain unresolved issues. In this study we constructed a deep-learning (DL) model to predict the need for oxygen supplementation using clinical information and chest CT images of patients with COVID-19.

MATERIALS AND METHODS

We retrospectively enrolled 738 patients with COVID-19 for whom clinical information (patient background, clinical symptoms, and blood test findings) was available and chest CT imaging was performed. The initial data set was divided into 591 training and 147 evaluation data. We developed a DL model that predicted oxygen supplementation by integrating clinical information and CT images. The model was validated at two other facilities (n = 191 and n = 230). In addition, the importance of clinical information for prediction was assessed.

RESULTS

The proposed DL model showed an area under the curve (AUC) of 89.9% for predicting oxygen supplementation. Validation from the two other facilities showed an AUC > 80%. With respect to interpretation of the model, the contribution of dyspnea and the lactate dehydrogenase level was higher in the model.

CONCLUSIONS

The DL model integrating clinical information and chest CT images had high predictive accuracy. DL-based prediction of disease severity might be helpful in the clinical management of patients with COVID-19.

Asthma and COPD as co-morbidities in patients hospitalised with Covid-19 disease: a global systematic review and meta-analysis

BACKGROUND

Factors predisposing to increased mortality with COVID-19 infection have been identified as male sex, hypertension, obesity, and increasing age. Early studies looking at airway diseases gave some contradictory results. The purpose of our study was to determine global variation in studies in patients hospitalized with COVID-19 in the prevalence of COPD and asthma; and to determine whether the presence of asthma or COPD affected mortality in the same hospital population.

METHODS

A systematic review and meta-analysis of the published literature of COPD and asthma as co-morbidities in patients hospitalized with COVID-19 was performed, looking firstly at the prevalence of these diseases in patients hospitalized with COVID-19, and secondly at the relative risk of death from any cause for patients with asthma or COPD.

RESULTS

Prevalence of both airway diseases varied markedly by region, making meaningful pooled global estimates of prevalence invalid and not of clinical utility. For individual studies, the interquartile range for asthma prevalence was 4.21 to 12.39%, and for COPD, 3.82 to 11.85%. The relative risk of death with COPD for patients hospitalized with COVID-19 was 1.863 (95% CI 1.640-2.115), while the risk with asthma was 0.918 (95% CI 0.767 to 1.098) with no evidence of increased mortality.

CONCLUSIONS

For asthma and COPD, prevalence in patients hospitalized with COVID-19 varies markedly by region. We found no evidence that asthma predisposed to increased mortality in COVID-19 disease. For COPD, there was clear evidence of an association with increased mortality.

TRIAL REGISTRATION

The trial was registered with PROSPERO: registration number CRD42021289886.

Listeria monocytogenes bacteremia developed during treatment of COVID-19

Listeria monocytogenes is an important pathogen in older patients and immunosuppressed patients, often causing bacteremia. Complications resulting from infections other than COVID-19 must also be considered during COVID-19 treatment.

Prevalence of overweight and obesity and their effect on COVID-19 severity and hospitalization among younger than 50 years versus older than 50 years population: A systematic review and meta-analysis

Cohort studies have shown that both overweight and obesity have their impact by increasing hospitalization with COVID-19. We conducted a systematic literature search in PubMed, Google Scholar, and MedRxiv databases following the PRISMA guidelines. Statistical analyses were performed using STATA software version 16 MP (Stata Corp, College Station, TX, USA) and Med Calc software version 22.009(Med Calc software Ltd, Ostend, Belgium). The primary outcome was to measure the prevalence of overweight and obesity and their impact on the risk of hospitalization among COVID-19 patients under and above 50 years of age. In total, 184 studies involving 2,365,377 patients were included. The prevalence of overweight was highest among those younger than 50 years of age over those older than 50 years of age, (26.33% vs. 30.46%), but there was no difference in obesity (36.30% vs. 36.02%). Overall, the pooled prevalence of overweight and obesity among hospitalized COVID-19 patients was 31.0% and 36.26%, respectively. Compared with normal weight, the odds of hospitalization with overweight (odds ratio [OR] 2.186, 95% confidence interval [CI] [1.19, 3.99], p < 0.01) and obesity (OR 3.069, 95% CI [1.67, 5.61], p < 0.001) in those younger than 50 years and obesity (OR 3.977, 95% CI [2.75, 5.73], p < 0.001) in the older than 50 years age group were significantly high. The increased prevalence of overweight and obesity among the under 50 years age group and obesity among the older than 50 years age group significantly increased the rate of COVID-19 infections, severity and hospitalization.

Associations of COVID-19 symptoms with omicron subvariants BA.2 and BA.5, host status, and clinical outcomes in Japan: a registry-based observational study

BACKGROUND

Previous SARS-CoV-2 infection and vaccination, coupled with the rapid evolution of SARS-CoV-2 variants, have modified COVID-19 clinical manifestations. We aimed to characterise the clinical symptoms of COVID-19 individuals in omicron BA.2 and BA.5 Japanese pandemic periods to identify omicron and subvariant associations between symptoms, immune status, and clinical outcomes.

METHODS

In this registry-based observational study, individuals registered in Sapporo's web-based COVID-19 information system entered 12 pre-selected symptoms, days since symptom onset, vaccination history, SARS-CoV-2 infection history, and background. Eligibility criteria included symptomatic individuals who tested positive for SARS-CoV-2 (PCR or antigen test), and individuals who were not tested for SARS-CoV-2 but developed new symptoms after a household member tested positive for SARS-CoV-2. Symptom prevalence, variables associated with symptoms, and symptoms associated with progression to severe disease were analysed.

FINDINGS

Data were collected and analysed between April 25 and Sept 25, 2022. For 157 861 omicron-infected symptomatic individuals, cough was the most common symptom (99 032 [62·7%] patients), followed by sore throat (95 838 [60·7%] patients), nasal discharge (69 968 [44·3%] patients), and fever (61 218 [38·8%] patients). Omicron BA.5 infection was associated with a higher prevalence of systemic symptoms than BA.2 in vaccinated and unvaccinated individuals (adjusted odds ratio [OR] for fever: 2·18 [95% CI 2·12-2·25]). Omicron breakthrough-infected individuals with three or more vaccinations or previous infection were less likely to exhibit systemic symptoms (fever 0·50 [0·49-0·51]), but more likely to exhibit upper respiratory symptoms (sore throat 1·33 [1·29-1·36]; nasal discharge 1·84 [1·80-1·89]). Infected older individuals (≥65 years) had lower odds for all symptoms. However, when symptoms were manifest, systemic symptoms were associated with increased odds for severe disease (dyspnoea 3·01 [1·84-4·91]; fever 2·93 [1·89-4·52]), whereas upper respiratory symptoms were associated with decreased odds (sore throat 0·38 [0·24-0·63]; nasal discharge 0·48 [0·28-0·81]).

INTERPRETATION

Host immunological status, omicron subvariant, and age were associated with a spectrum of COVID-19 symptoms and outcomes. BA.5 produced a higher systemic symptom prevalence than BA.2. Vaccination and previous infection reduced systemic symptom prevalence and improved outcomes but increased upper respiratory tract symptom prevalence. Systemic, but not upper respiratory, symptoms in older people heralded severe disease. Our findings could serve as a practical guide to use COVID-19 symptoms to appropriately modify health-care strategies and predict clinical outcomes for older patients with omicron infections.

FUNDING

Japan Agency for Medical Research and Development.

Prognostic value of ECG monitor findings in COVID-19

AIMS

COVID-19 can cause severe illness and multiorgan dysfunction. Acute myocardial damage has been detected in a significant portion of patients with COVID-19; therefore, several studies have reported that electrocardiographic findings could be used to evaluate the severalty of COVID-19. However, performing standard ECG for each patient hospitalised with COVID-19 can increase the level of exposure to COVID-19 among medical staff. Therefore, this study aimed to investigate the prognostic value of continuous electrocardiographic monitor findings in patients with COVID-19.

METHODS

Among 1612 consecutive patients with COVID-19 who were admitted to our hospital between August 2021 and May 2022, we identified 96 (76±4 years) patients who underwent electrocardiographic monitor during hospitalisation. All electrocardiographic monitors were analysed by two independent cardiologists blinded to the clinical data of the patients. The endpoint was defined as the occurrence of all-cause mortality related to COVID-19. The event data were retrospectively gathered from the patients' medical records. A multivariate Cox model was used to assess whether these electrocardiographic monitor findings and clinical data were associated with in-hospital mortality.

RESULTS

During a mean hospitalisation period of 22.8±3.2 days, in-hospital mortality occurred in 17 (18%) patients. Atrial fibrillation (HR: 3.95, 95% CI: 1.39 to 11.21) and lung disease complications (HR: 2.91, 95% CI: 1.06 to 7.98) were significant prognostic factors for death in multivariate analysis. Compared with the non-complicated lung disease and non-atrial fibrillation group, the risk of mortality was significantly higher in the lung disease complication and atrial fibrillation group in the multivariate Cox proportional model (HR: 8.37, 95% CI: 1.69 to 41.30, p=0.009).

CONCLUSIONS

The simple method of ECG monitor could adequately detect atrial fibrillation. This study demonstrated that atrial fibrillation complicated with lung disease, could have potential prognostic value among patients with COVID-19.

Impact of prediabetes with a high risk of diabetes stratified by glycated hemoglobin level on the severity of coronavirus disease 2019 during admission

Objective

Prediabetes with a glycated hemoglobin (HbA1c) level of 5.7 - 6.4% is associated with a poor prognosis of coronavirus disease 2019 (COVID-19), but whether the degree of glycemic control is associated with COVID-19 severity is unknown. The aim of this study was to evaluate the association between the degree of glycemic control and COVID-19 severity in patients with prediabetes.

Materials and methods

We reviewed 254 patients with COVID-19 admitted to our hospital between April 2020 and September 2021. Based on their HbA1c level, patients were classified into low (HbA1c level < 5.7%), moderate (HbA1c level, 5.7 - 5.9%), and high risk of diabetes (HbA1c level, 6.0 - 6.4%). The association between risk of diabetes and the worst COVID-19 symptom in terms of severity during admission was evaluated using binary logistic regression analysis.

Results

Seventy-one and 88 patients had moderate and high risks of diabetes, respectively. Sixty-three and seven patients presented severe (requiring non-invasive oxygen therapy) or critical (intensive care unit admission or artificial respiratory management) COVID-19. The multivariate logistic regression analysis showed that a high risk of diabetes was correlated with severe COVID-19 (P = 0.01) after adjusting for baseline characteristics, whereas a moderate risk of diabetes was not (P = 0.17).

Conclusion

Prediabetes with a high risk of diabetes is associated with the worst COVID-19 symptom in terms of severity during admission. Our findings could aid in more efficient allocation of healthcare resources to a narrower population of prediabetic patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00643-z.

COVID-19 fatality rates in hospitalized patients: A new systematic review and meta-analysis

BACKGROUND

SARS-COV2 or COVID-19 disease is an infectious illness that emerged for the first time at the end of 2019, in Wuhan, China and rapidly turned out to be an international pandemic with deleterious effects all over the world. In March 2021, A. Macedo et al., has published the first meta-analysis of hospital mortality, so the authors decided to update those data at a time of emergence of new therapies and increasing vaccination rates.

METHODS

As the outcome of interest was the mortality in hospitalized general patients, the authors looked for articles evaluating the clinical characteristics of those patients, consulting PUBMED (The US National Library of Medicine) and EMBASE (Medical database) in an independent selection using predefined terms of search. A meta-analysis random-effect model was estimated using Mantel-Haenszel method. Heterogeneity among studies was tested using Tau2 statistics and Chi2 statistics.

RESULTS

In a first instance 25 articles were included for final analysis with a total of 103,840 patients, but as the goal was to update the anterior data, these studies were analysed together with the 21 studies of the previous meta-analysis, with a total of 114609 patients. The mortality rate of COVID-19 general patients admitted to the hospital was 16% (95% CI 12; 21, I2 =100%).

CONCLUSION

Global hospital mortality of COVID-19 of general patients was 16%, with quite different rates according to the different geographic areas analysed.

Modified Early Warning Score: Clinical Deterioration of Mexican Patients Hospitalized with COVID-19 and Chronic Disease

The objective was to evaluate the Modified Early Warning Score in patients hospitalized for COVID-19 plus chronic disease.

METHODS

Retrospective observational study, 430 hospitalized patients with COVID-19 and chronic disease. Instrument, Modified Early Warning Score (MEWS). Data analysis, with Cox and logistic regression, to predict survival and risk.

RESULTS

Of 430 patients, 58.6% survived, and 41.4% did not. The risk was: low 53.5%, medium 23.7%, and high 22.8%. The MEWS score was similar between survivors 3.02, p 0.373 (95% CI: -0.225-0.597) and non-survivors 3.20 (95% CI: -0.224-0.597). There is a linear relationship between MEWS and mortality risk R 0.920, ANOVA 0.000, constant 4.713, and coefficient 4.406. The Cox Regression p 0.011, with a risk of deterioration of 0.325, with a positive coefficient, the higher the risk, the higher the mortality, while the invasive mechanical ventilation coefficient was negative -0.757. By providing oxygen and ventilation, mortality is lower.

CONCLUSIONS

The predictive value of the modified early warning score in patients hospitalized for COVID-19 and chronic disease is not predictive with the MEWS scale. Additional assessment is required to prevent complications, especially when patients are assessed as low-risk.

Analysis of the Factors That Affect the Detection Duration of SARS-CoV-2 in Loop Mediated Isothermal Amplification among COVID-19 Inpatients

In COVID-19 patients who are immunocompromised or have severe COVID-19, the duration of infectious viral shedding may be longer, and a longer isolation duration is recommended. At the National Sagamihara Hospital, a decline in the viral load to end the isolation of hospitalized patients with COVID-19 was confirmed using loop-mediated isothermal amplification (LAMP). However, a subset of patients displayed LAMP positivity for more than 20 days after symptom onset. Therefore, we conducted a retrospective observational study to investigate the factors that affect the persistence of LAMP positivity. This study included a total of 102 participants. The severity of COVID-19 was mild (25.5%), moderate (67.6%), or severe (6.9%). The median number (interquartile range) of days until negative LAMP results from symptom onset were 16 (14-19) days. Multivariate logistic regression analysis showed that patients ≥55 years and/or those with the delta variant were correlated with persistent LAMP positivity for more than 20 days after symptom onset. This study identified age, the delta variant, and oxygen requirement as factors that contribute to persistently positive LAMP results. Therefore, it is posited that in these patients, the implementation of LAMP for deisolation would result in a prolonged isolation duration.

Retrospective Case-Control Study of REGEN-COV (Casirivimab and Imdevimab) Therapy for Patients with COVID-19 and Cancer Using the United States MarketScan® Database

INTRODUCTION

Patients with cancer may be at a higher risk of experiencing severe complications from coronavirus disease 2019 (COVID-19) than are patients without cancer. This study evaluated the efficacy of REGEN-COV, a combination of the monoclonal antibodies casirivimab and imdevimab, for treating COVID-19 in patients with cancer in the USA.

METHODS

Using the MarketScanⓇ database, de-identified data of patients with a COVID-19 diagnosis between November 1, 2020, and November 30, 2021, were analyzed. In the preliminary study, patients with COVID-19 were divided into two groups: those with and without cancer within 1 year prior to a COVID-19 diagnosis. In the main study, patients with COVID-19 with cancer were divided into two groups: those with and without REGEN-COV treatment. Patient outcomes, such as COVID-19-derived hospitalization, hospitalization duration, and medical costs, were assessed between these two groups by propensity score matching.

RESULTS

Within the first 30 days of a COVID-19 diagnosis, the group treated with REGEN-COV had fewer hospitalizations (3.2% vs. 13.3%; p < 0.001), fewer mean hospitalization days (0.2 vs. 1.1 days; p < 0.001), and a lower mean-associated medical payment (2,709 vs. 8,120 USD; p < 0.001) than the group not treated with REGEN-COV. Patients with specific cancer types, including non-Hodgkin's lymphoma, leukemia, and lung cancer, had higher hospitalization rates than those with other cancer types.

CONCLUSION

Patients with cancer treated with REGEN-COV experienced a decreased risk for hospitalization, hospitalization duration, and total COVID-19-related costs. Patients with cancer were at a higher risk of being hospitalized for COVID-19 than were those without cancer. The use of neutralizing antibody therapy may reduce the risk of severe COVID-19 infection for patients with cancer with an otherwise high risk. Future replication studies should be conducted using other databases that include Medicaid users and other insured persons for comparison and validation.

Assessment of hospitalisation costs and their determinants among Covid-19 patients in South Central Ethiopia

BACKGROUND

The coronavirus disease 2019 (Covid-19) pandemic is a global public health problem. The Covid-19 pandemic has had a substantial impact on the economy of developing countries, including Ethiopia.This study aimed to determine the hospitalisation costs of Covid-19 and the factors associated with the high cost of hospitalisation in South Central Ethiopia.

METHODS

A retrospective cost analysis of Covid-19 patients hospitalised between July 2020 and July 2021 at Bokoji Hospital Covid-19 Treatment Centre was conducted using both the micro-costing and top-down approaches from the health system perspective. This analysis used cost data obtained from administrative reports, the financial reports of the treatment centre, procurement invoices and the Covid-19 standard treatment guidelines. The Student's t-test, Mann-Whitney U test or Kruskal-Wallis test was employed to test the difference between sociodemographic and clinical factors when appropriate.To identify the determinants of cost drivers in the study population, a generalised linear model with gamma distribution and log link with a stepwise algorithm were used.

RESULTS

A total of 692 Covid-19 patients were included in the costing analysis. In this study, the mean cost of Covid-19-infected patients with no symptoms was US$1,073.86, with mild symptoms US$1,100.74, with moderate symptoms US$1,394.74 and in severe-critically ill condition US$1,708.05.The overall mean cost was US$1,382.50(95% CI: 1,360.60-1,404.40) per treated episode.The highest mean cost was observed for personnel, accounting for 64.0% of the overall cost. Older age, pre-existing diseases, advanced disease severity at admission, admission to the intensive care unit, prolonged stay on treatment and intranasal oxygen support were strongly associated with higher costs.

CONCLUSIONS

This study found that the clinical management of Covid-19 patients incurred significant expenses to the health system. Factors such as older age, disease severity, presence of comorbidities, use of inhalation oxygen therapy and prolonged hospital stay were associated with higher hospitalisation costs.Therefore, the government should give priority to the elderly and those with comorbidities in the provision of vaccination to reduce the financial burden on health facilities and health systems in terms of resource utilisation.

Reliability of the respiratory rate and oxygenation index for successful high-flow nasal cannula support in coronavirus disease pneumonia: a retrospective cohort study

BACKGROUND

High-flow nasal cannula (HFNC) therapy is an important non-invasive respiratory support in acute respiratory failure, including coronavirus disease (COVID-19) pneumonia. Although the respiratory rate and oxygenation (ROX) index is a simple and useful predictor for HFNC failure and mortality, there is limited evidence for its use in patients with COVID-19 pneumonia. We aimed to evaluate the ROX index as a predictor for HFNC failure in patients with COVID-19 pneumonia. We also evaluated the ROX index as a predictor for 28-day mortality.

METHODS

In this single-center, retrospective, cohort study, 248 patients older than 18 years of age with COVID-19 pneumonia received HFNC therapy for acute respiratory failure. The ROX index was evaluated within 4 h from the start of HFNC therapy. Past medical history, laboratory data, and the ROX index were evaluated as predictors for HFNC failure and 28-day mortality.

RESULTS

The ROX index < 4.88 showed a significantly high risk ratio for HFNC failure (2.13 [95% confidence interval [CI]: 1.47 - 3.08], p < 0.001). The ROX index < 4.88 was significantly associated with 28-day mortality (p = 0.049) in patients with COVID-19 pneumonia receiving HFNC therapy. Age, chronic hypertension, high lactate dehydrogenase level, and low ROX index showed significantly high risk ratio for HFNC failure. C-reactive protein level and low ROX index were predictors of 28-day morality.

CONCLUSION

The ROX index is a useful predictor for HFNC success and 28-day mortality in patients with COVID-19 pneumonia receiving HFNC therapy.

TRIAL REGISTRATION

An independent ethics committee approved the study (Research Ethics Review Committee of Kobe City Medical Center General Hospital [number: zn220303; date: February 21, 2022]), which was performed in accordance with the Declaration of Helsinki, Guidelines for Good Clinical Practice.

Were metabolic and other chronic diseases the driven onset epidemic forces of COVID-19 in Mexico?

The underline hypothesis of this study was that SARS-CoV-2 can infect individuals regardless of health condition, sex, and age in opposition to the classical epidemiological assumption of an identifiable susceptible subpopulation for epidemic development. To address this issue, a population cohort with 24.4 million metadata associated with 226,089 official RT-qPCR positive and 283,450 negative cases, including 27,769 deceased, linked putatively to B.1. and B.1.1. SARS-CoV-2 lineages were analyzed. The analysis baseline was to determine the infection and mortality structure of the diseased cohort at the onset-exponential phase of the first epidemic wave in Mexico under the assumption of limited herd immunity. Individuals with nonchronic diseases (NOCDs) were compared with those exhibiting at least one of 10 chronic diseases (CDs) adjusted by age and sex. Risk factors for infection and mortality were estimated with classification and regression tree (CART) and cluster analysis based on Spearman's matrix of rho-values in RStudio®, complemented with two proposed mortality indices. SARS-CoV-2 infection was independent of health condition (52.8% NOCD vs. 47.2% CDs; p = 0.001-0.009) but influenced by age >46 in one risk analysis scenario (p < 0.001). Sex contributed 9.7% to the overall risk. The independent effect was supported by the health structure of negative cases with a similar tendency but a higher proportion of NOCDs (61.4%, p = 0.007). The infection probability in individuals with one CD was determined by the disease type and age, which was higher in those older individuals (≥56 years) exhibiting diabetes (12.3%, cp = 0.0006), hypertension (10.1%, cp < 0.0001), and obesity (7.8%, cp = 0.001). In contrast, the mortality risk was heavily influenced by CD conditioned by sex and age, accounting for 72.3% of total deaths (p = 0.001-0.008). Significant mortality risk (48%) was comprised of women and men (w, m) aged ≥56 years with diabetes (19% w and 27.9% m, cp < 0.0004), hypertension (11.5% w, cp = 0.0001), and CKD (3.5% w and 5.3% m, cp = 0.0009). Older people with diabetes and hypertension comorbidity increased the risk to 60.5% (p = 0.001). Based on a mortality-weighted index, women were more vulnerable to preexisting metabolic or cardiovascular diseases. These findings support our hypothesis and justify the need for surveillance systems at a communitarian level. This is the first study addressing this fundamental epidemiological question.

Impact of body composition on patient prognosis after SARS-Cov-2 infection

BACKGROUND

Since the first outbreak of coronavirus disease 2019 (COVID-19), it has been reported that several factors, including hypertension, type 2 diabetes mellitus, and obesity, have close relationships with a severe clinical course. However, the relationship between body composition and the prognosis of COVID-19 has not yet been fully studied.

METHODS

The present study enrolled 76 consecutive COVID-19 patients with computed tomography (CT) scans from the chest to the pelvis at admission. The patients who needed intubation and mechanical ventilation were defined as severe cases. Patients were categorized into four groups according to their body mass index (BMI). The degree of hepatic steatosis was estimated by the liver/spleen (L/S) ratio of the CT values. Visceral fat area (VFA), psoas muscle area (PMA), psoas muscle mass index (PMI), and intra-muscular adipose tissue content (IMAC) were measured by CT scan tracing. These parameters were compared between non-severe and severe cases.

RESULTS

Severe patients had significantly higher body weight, higher BMI, and greater VFA than non-severe patients. However, these parameters did not have an effect on disease mortality. Furthermore, severe cases had higher IMAC than non-severe cases in the non-obese group.

CONCLUSIONS

Our data suggest high IMAC can be a useful predictor for severe disease courses of COVID-19 in non-obese Japanese patients, however, it does not predict either disease severity in obese patients or mortality in any obesity grade.

Development and Validation of a Prediction Model of the Risk of Pneumonia in Patients with SARS-CoV-2 Infection

Objective

To establish a prediction model of pneumonia risk in SARS-CoV-2-infected patients to reduce unnecessary chest CT scans.

Materials and Methods

The model was constructed based on a retrospective cohort study. We selected SARS-CoV-2 test-positive patients and collected their clinical data and chest CT images from the outpatient and emergency departments of Hunan Provincial People's Hospital, China. Univariate and multivariate logistic regression and least absolute shrinkage and selection operator (LASSO) regression were utilized to identify predictors of pneumonia risk for patients infected with SARS-CoV-2. These predictors were then incorporated into a nomogram to establish the model. To ensure its performance, the model was evaluated from the aspects of discrimination, calibration, and clinical validity. In addition, a smoothed curve was fitted using a generalized additive model (GAM) to explore the association between the pneumonia grade and the model's predicted probability of pneumonia.

Results

We selected 299 SARS-CoV-2 test-positive patients, of whom 205 cases were in the training cohort and 94 cases were in the validation cohort. Age, CRP natural log-transformed value (InCRP), and monocyte percentage (%Mon) were found to be valid predictors of pneumonia risk. This predictive model achieved good discrimination of AUC in the training and validation cohorts which was 0.7820 (95% CI: 0.7254-0.8439) and 0.8432 (95% CI: 0.7588-0.9151), respectively. At the cut-off value of 0.5, it had a sensitivity and specificity of 70.75% and 66.33% in the training cohort and 76.09% and 73.91% in the validation cohort, respectively. With suitable calibration accuracy shown in calibration curves, decision curve analysis indicated high clinical value in predicting pneumonia probability in SARS-CoV-2-infected patients. The probability of pneumonia predicted by the model was positively correlated with the actual pneumonia classification.

Conclusion

This study has developed a pneumonia risk prediction model that can be utilized for diagnostic purposes in predicting the probability of pneumonia in patients infected with SARS-CoV-2.

Pulmonary embolism and deep venous thrombosis after COVID-19: long-term risk in a population-based cohort study

Background

Venous thromboembolism (VTE) (pulmonary embolism (PE) or deep venous thrombosis (DVT)) is common during acute COVID-19. Long-term excess risk has not yet been established.

Objective

To study long-term VTE risk after COVID-19.

Methods

Swedish citizens aged 18-84 years, hospitalized and/or testing positive for COVID-19 between January 1, 2020, and September 11, 2021 (exposed), stratified by initial hospitalization, were compared to matched (1:5) non-exposed population-derived subjects without COVID-19. Outcomes were incident VTE, PE or DVT recorded within 60, 60-<180, and ≥180 days. Cox regression was used for evaluation and a model adjusted for age, sex, comorbidities and socioeconomic markers developed to control for confounders.

Results

Among exposed patients, 48,861 were hospitalized for COVID-19 (mean age 60.6 years) and 894,121 were without hospitalization (mean age 41.4 years). Among patients hospitalized for COVID-19, fully adjusted hazard ratios (HRs) during 60-<180 days were 6.05 (95% confidence interval (CI) 4.80─7.62) for PE and 3.97 (CI 2.96─5.33) for DVT, compared to non-exposed with corresponding estimates among COVID-19 without hospitalization 1.17 (CI 1.01─1.35) and 0.99 (CI 0.86─1.15), based on 475 and 2,311 VTE events, respectively. Long-term (≥180 days) HRs in patients hospitalized for COVID-19 were 2.01 (CI 1.51─2.68) for PE and 1.46 (CI 1.05─2.01) for DVT while non-hospitalized had similar risk to non-exposed, based on 467 and 2,030 VTE events, respectively.

Conclusions

Patients hospitalized for COVID-19 retained an elevated excess risk of VTE, mainly PE, after 180 days, while long-term risk of VTE in individuals with COVID-19 without hospitalization was similar to the non-exposed.

The liver-to-spleen ratio is a risk factor predicting oxygen demand in COVID-19 patients

Background

We aimed to investigate risk factors predicting oxygen demand in COVID-19 patients.

Methods

Patients admitted to Shizuoka General Hospital with COVID-19 from August 2020 to August 2021 were included. First, we divided patients into groups with and without oxygen demand. Then, we compared patients' clinical characteristics and laboratory and radiological findings to determine factors predicting oxygen demand.

Results

One hundred seventy patients with COVID-19 (aged 58±15 years, 57 females) were enrolled. Common comorbidities were cardiovascular diseases (47.6%), diabetes mellitus (28.8%), and dyslipidemia (26.5%). Elder age, higher body mass index, cardiovascular diseases, diabetes mellitus, lower lymphocyte count, albumin, hepatic attenuation value, and the liver-to-spleen ratio (L/S), higher D-dimer, aspartate aminotransferase, lactate dehydrogenase, troponin-T, C-reactive protein, KL-6, chest and abdominal circumference, and visceral fat were found in patients with oxygen demand. According to the multivariate logistic regression analysis, L/S, lymphocyte count, D-dimer, and abdominal circumference under the diaphragm were independent risk factors predicting oxygen demand in COVID-19 patients.

Conclusions

On admission, L/S, lymphocyte count, D-dimer, and abdominal circumference were predictive factors for oxygen demand. These factors may help in the appropriate triage of COVID-19 patients in the decision to admit them to the hospital.

Nirmatrelvir/Ritonavir for hemodialysis patients with COVID-19

Background: Hemodialysis patients have a high risk of severe/critical COVID-19 and related high mortality, but nirmatrelvir/ritonavir is not recommended for hemodialysis patients with COVID-19 infection because of lack of evidence of safety. Objectives: Our study aims to evaluate the minimum plasma concentration (Cmin) of nirmatrelvir and its safety of different doses of nirmatrelvir/ritonavir in hemodialysis patients with mild COVID-19. Method: This was a prospective, two step, nonrandomized, open-label study. Participants were treated with nirmatrelvir 150 mg or 300 mg once a day (another 75 mg or 150 mg supplied after hemodialysis) and ritonavir 100 mg twice daily for 5 days, respectively. The primary outcome was the safety of nirmatrelvir/ritonavir, including the Cmin of nirmatrelvir and the number of adverse events (AE). The secondary outcome was the time of viral elimination in hemodialysis patients. Results: Adverse events were happened in 3 and 7 participants in the step 1 and step 2 group, respectively (p = 0.025). Among them, 2 and 6 participants were identified as drug-related adverse events (p = 0.054). No SAE or liver function damage happened. The Cmin of nirmatrelvir in step 1 and step 2 group were 5,294.65 ± 2,370.59 ng/mL and 7,675.67 ± 2,745.22 ng/mL (p = 0.125). The Cmin of the control group was 2,274.10 ± 1,347.25 ng/mL (p = 0.001 compared to step 2 and p = 0.059 compared to step 1). Compared to hemodialysis patients without nirmatrelvir/ritonavir, there were no statistical differences in overall viral elimination time (p = 0.232). Conclusion: In our study, two doses of nirmatrelvir/ritonavir appeared to be excessive for hemodialysis patients. Although all of the patients tolerated 5-day administration, nearly half of the patients experienced drug-related adverse events. In addition, the medication group did not show a significant advantage in the time of viral elimination.

Global prevalence and effect of comorbidities and smoking status on severity and mortality of COVID-19 in association with age and gender: a systematic review, meta-analysis and meta-regression

A COVID-19 patient often presents with multiple comorbidities and is associated with adverse outcomes. A comprehensive assessment of the prevalence of comorbidities in patients with COVID-19 is essential. This study aimed to assess the prevalence of comorbidities, severity and mortality with regard to geographic region, age, gender and smoking status in patients with COVID-19. A systematic review and multistage meta-analyses were reported using PRISMA guidelines. PubMed/MEDLINE, SCOPUS, Google Scholar and EMBASE were searched from January 2020 to October 2022. Cross-sectional studies, cohort studies, case series studies, and case-control studies on comorbidities reporting among the COVID-19 populations that were published in English were included. The pooled prevalence of various medical conditions in COVID-19 patients was calculated based on regional population size weights. Stratified analyses were performed to understand the variations in the medical conditions based on age, gender, and geographic region. A total of 190 studies comprising 105 million COVID-19 patients were included. Statistical analyses were performed using STATA software, version 16 MP (StataCorp, College Station, TX). Meta-analysis of proportion was performed to obtain pooled values of the prevalence of medical comorbidities: hypertension (39%, 95% CI 36-42, n = 170 studies), obesity (27%, 95% CI 25-30%, n = 169 studies), diabetes (27%, 95% CI 25-30%, n = 175), and asthma (8%, 95% CI 7-9%, n = 112). Moreover, the prevalence of hospitalization was 35% (95% CI 29-41%, n = 61), intensive care admissions 17% (95% CI 14-21, n = 106), and mortality 18% (95% CI 16-21%, n = 145). The prevalence of hypertension was highest in Europe at 44% (95% CI 39-47%, n = 68), obesity and diabetes at 30% (95% CI, 26-34, n = 79) and 27% (95%CI, 24-30, n = 80) in North America, and asthma in Europe at 9% (95% CI 8-11, n = 41). Obesity was high among the ≥ 50 years (30%, n = 112) age group, diabetes among Men (26%, n = 124) and observational studies reported higher mortality than case-control studies (19% vs. 14%). Random effects meta-regression found a significant association between age and diabetes (p < 0.001), hypertension (p < 0.001), asthma (p < 0.05), ICU admission (p < 0.05) and mortality (p < 0.001). Overall, a higher global prevalence of hypertension (39%) and a lower prevalence of asthma (8%), and 18% of mortality were found in patients with COVID-19. Hence, geographical regions with respective chronic medical comorbidities should accelerate regular booster dose vaccination, preferably to those patients with chronic comorbidities, to prevent and lower the severity and mortality of COVID-19 disease with novel SARS-CoV-2 variants of concern (VOC).

Comparison of Three Prognostic and Predictive Scores in 10 Patients with COVID-19 Pneumonia Caused by Nosocomial Infection

Introduction

A nosocomial outbreak of coronavirus disease (COVID-19) occurred in the Toda Chuo General Hospital in Toda City, Saitama Prefecture, Japan in December 2020. The purpose of this study was to compare the accuracy of three prognostic indices for predicting the outcome of COVID-19 in patents with COVID-19 pneumonia.

Patients and Methods

Patients in the Department of Urology and Transplant Surgery at Toda Chuo General Hospital with nosocomially acquired COVID-19 confirmed by a positive polymerase chain reaction test were included in the study. We used the COVID-GRAM, International Severe Acute Respiratory and Emerging Infections Consortium’s World Health Organization 4C Mortality Score, and COVID-19 Registry Japan to independently predict the prognoses of 10 patients and identify common prognostic factors. All three indices include age, dyspnea, and comorbidities as prognostic factors.

Results

Ten patients were included in the study, of which two patients died. According to the COVID-GRAM both patients were “high risk,” whereas the 4C Mortality Score predicted “high risk” and “very high risk.”

Conclusion

The prognostic scores of all three indices were useful for predicting illness severity.

Safety and Effectiveness of Molnupiravir (LAGEVRIO®) Capsules in Japanese Patients with COVID-19: Interim Report of Post-marketing Surveillance in Japan

INTRODUCTION

Molnupiravir is an oral antiviral drug that received special approval for emergency use in Japan on December 24 2021 for infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This post-marketing surveillance (PMS) is underway to investigate the safety and effectiveness of molnupiravir in daily clinical practice in Japan. The interim PMS data collected from December 27 2021 to June 15 2022 are reported in this publication.

METHODS

This survey included adult Japanese patients treated with molnupiravir. For safety, adverse drug reactions (ADR) were assessed by physicians. Effectiveness was assessed by the composite endpoint of (1) hospitalization or (2) death in outpatients and by the composite endpoint of (3) death or (4) initiation of oxygen administration/mechanical ventilation in inpatients hospitalized for any reasons and without oxygen administration at the start of molnupiravir administration. The observation period was through 29 days from the start of molnupiravir administration.

RESULTS

Of the 1031 patients in the safety analysis set, 68 (6.60%) patients reported ADRs and four (0.39%) patients reported serious ADRs. The main ADRs observed were diarrhoea [26 patients (2.52%)], rash [six patients (0.58%)], dizziness [five patients (0.48%)], and faeces soft [four patients (0.39%)]. In the effectiveness analysis from the start date of molnupiravir administration to day 29, there were 16/612 (2.61%) hospitalizations and no deaths. Oxygen administration was newly initiated in 9/199 (4.52%) inpatients after the initiation of molnupiravir administration; 2/199 (1.01%) inpatients died.

CONCLUSION

This interim analysis of molnupiravir in daily clinical practice use in Japan supports the safety and effectiveness profile of molnupiravir under pandemic conditions in which Omicron was the dominant SARS-CoV-2 variant. The results of this PMS will provide valuable information for daily clinical practice use.

Mortality-associated Risk Factors in Hospitalized COVID-19 Patients in Japan: Findings of the CLOT-COVID Study

BACKGROUND

Reports of mortality-associated risk factors in patients with the novel coronavirus disease 2019 (COVID-19) are limited.

METHODS

We evaluated the clinical features that were associated with mortality among patients who died during hospitalization (n = 158) and those who were alive at discharge (n = 2,736) from the large-scale, multicenter, retrospective, observational cohort CLOT-COVID study, which enrolled consecutively hospitalized COVID-19 patients from 16 centers in Japan from April to September 2021. Data from 2,894 hospitalized COVID-19 participants of the CLOT-COVID study were analyzed in this study.

RESULTS

Patients who died were older (71.1 years vs 51.6 years, P < 0.001), had higher median D-dimer values on admission (1.7 µg/mL vs 0.8 µg/mL, P < 0.001), and had more comorbidities. On admission, the patients who died had more severe COVID-19 than did those who survived (mild: 16% vs 63%, moderate: 47% vs 31%, and severe: 37% vs 6.2%, P < 0.001). In patients who died, the incidence of thrombosis and major bleeding during hospitalization was significantly higher than that in those who survived (thrombosis: 8.2% vs 1.5%, P < 0.001; major bleeding: 12.7% vs 1.4%, P < 0.001). Multivariable logistic regression analysis revealed that age >70 years, high D-dimer values on admission, heart disease, active cancer, higher COVID-19 severity on admission, and development of major bleeding during hospitalization were independently associated with a higher mortality risk.

CONCLUSION

This large-scale observational study in Japan identified several independent risk factors for mortality in hospitalized patients with COVID-19 that could facilitate appropriate risk stratification of patients with COVID-19.

Comparison of the clinical characteristics and outcomes of Japanese patients with COVID-19 treated in primary, secondary, and tertiary care facilities

AIM

To compare the characteristics and clinical course of patients with coronavirus disease (COVID-19) according to the healthcare level of the admitted hospital, to provide an insight into determining the appropriate level of care for each patient.

METHODS

This retrospective, observational study utilized data from the COVID-19 Registry Japan (COVIREGI-JP), the largest Japanese registry of hospitalized patients with COVID-19. Datasets were obtained from reports filed as of May 31, 2022.

RESULTS

A total of 59,707 patients (2004 in the primary care group, 41,420 in the secondary care group, and 16,283 in the tertiary care group) from 585 facilities were included in the analysis. Patients with established risk factors for severe disease, such as old age and the presence of comorbidities, were treated at higher care facilities and had poorer initial conditions and in-hospital clinical course, as well as higher mortality. Analysis of the fatality rates for each complication suggested that patients with complications requiring procedures (e.g. pleural effusions, myocardial ischemia, and arrhythmia) may have better survival rates in facilities with specialist availability. The number of deaths and severe COVID-19 cases in this study were notably less than those reported overseas.

CONCLUSION

Our results showed that more difficult COVID-19 cases with poor outcomes were treated at higher care level facilities in Japan. Attending to possible complications may be useful for selecting an appropriate treatment hospital. Healthcare providers need to maintain a broad perspective on the distribution of medical resources.

COVID-19 vaccination benefits in preventing severe disease in mild-to-moderate cases: An analysis in the first specialized hospital for COVID-19 in Japan

BACKGROUND

In Japan, the fourth round of coronavirus disease (COVID-19) vaccination is ongoing and is targeted at medical staff and nursing home workers, individuals aged ≥60 years, and those with comorbidities or other high-risk factors, including body mass index (BMI) ≥30 kg/m². The incidence of severe COVID-19 decreased markedly after widespread COVID-19 vaccination drives, and our hospital experienced a similar trend. We, therefore, examined the characteristics of our patients to clarify who benefited the most from vaccination.

METHODS

We retrospectively investigated all patients hospitalized for COVID-19 in Osaka City Juso Hospital between March 1, 2021, and June 30, 2022. Using multivariable logistic analysis, we calculated the adjusted odds ratios (aORs) for severe disease after vaccination in the whole dataset and in subsets stratified by age, sex, BMI, smoking history, pre-hospitalization location, and comorbidities.

RESULTS

The analysis included 1041 patients. Multivariable logistic analysis showed that vaccination was associated with a low risk of severe disease, with an aOR of 0.21 (95% confidence interval: 0.12-0.36, p < 0.001). On stratifying the analysis according to background characteristics, lower aORs for severe COVID-19 were found for patients aged ≥60 years and for those with diabetes or hypertension. Notably, patients with BMI >30 kg/m² and those with BMI ≥18 kg/m² and ≤30 kg/m² benefited from vaccination.

CONCLUSIONS

Individuals with diabetes or hypertension and those of age ≥60 years benefited more from vaccination than did their counterparts. We recommend extending the fourth round of vaccinations to individuals with a BMI of 18-30 kg/m².

Low Dietary Variety Is Associated with Incident Frailty in Older Adults during the Coronavirus Disease 2019 Pandemic: A Prospective Cohort Study in Japan

BACKGROUND

Stagnation of social activity due to the COVID-19 pandemic probably reduces motivation to maintain a healthy diet. It is important to report on the dietary changes observed in older adults during a period of restriction on outings and to clarify the relationship between dietary variety and frailty. This one-year follow-up study examined the association between frailty and dietary variety during the COVID-19 pandemic.

METHODS

Baseline and follow-up surveys were conducted in August 2020 and August 2021, respectively. The follow-up survey was distributed by mail to 1635 community-dwelling older adults aged ≥65 years. Of the 1235 respondents, 1008 respondents who were non-frail at baseline are included in this study. Dietary variety was examined using a dietary variety score developed for older adults. Frailty was assessed using a five-item frailty screening tool. The outcome was frailty incidence.

RESULTS

In our sample, 108 subjects developed frailty. A linear regression analysis revealed a significant association between dietary variety score and frailty score (β, -0.032; 95% CI, -0.064 to -0.001; p = 0.046). This association was also significant in Model 1, adjusted for sex and age, (β, -0.051; 95% CI, -0.083 to -0.019; p = 0.002) and in a multivariate analysis that added adjustments for living alone, smoking, alcohol use, BMI, and existing conditions to Model 1 (β, -0.045; 95% CI, -0.078 to -0.012; p = 0.015).

CONCLUSIONS

A low dietary variety score was associated with an increased frailty score during the COVID-19 pandemic. The restricted daily routine caused by the COVID-19 pandemic will probably continue to have a long-term effect in terms of reduced dietary variety. Thus, vulnerable populations, such as older adults, might require dietary support.

Association Between the Development of Thrombosis and Worsening of Disease Severity in Patients With Moderate COVID-19 on Admission - From the CLOT-COVID Study

BACKGROUND

The worsening of coronavirus disease 2019 (COVID-19) severity is a critical issue in current clinical settings and may be associated with the development of thrombosis.

METHODS AND RESULTS

This study used patient data obtained in the CLOT-COVID study, a retrospective multicenter cohort study. The demographics of patients with moderate COVID-19 on admission with and without worsened severity during hospitalization were compared and predictors were identified. Of 927 patients with moderate COVID-19 on admission, 182 (19.6%) had worsened severity during hospitalization. Patients with worsening of severity were older, more likely to have hypertension, diabetes, heart disease, and active cancer, and more likely to use pharmacological thromboprophylaxis. Patients with worsening of severity had higher D-dimer levels on admission and were more likely to develop thrombosis and major bleeding during hospitalization than those without worsening. Increased age (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 1.01-1.03, P=0.005), diabetes (OR: 1.63, 95% CI: 1.11-2.33, P=0.012), D-dimer levels >1.0 μg/mL on admission (OR: 2.10, 95% CI: 1.45-3.03, P<0.001), and thrombosis (OR: 6.28, 95% CI: 2.72-14.53, P<0.001) were independently associated with worsening of COVID-19 severity.

CONCLUSIONS

Approximately 20% of patients with moderate COVID-19 had worsened severity during hospitalization. Increased age, diabetes, D-dimer levels >1.0 μg/mL on admission, and the development of thrombosis during hospitalization were significantly associated with worsened COVID-19 severity.

Intravenous methylprednisolone pulse therapy and the risk of in-hospital mortality among acute COVID-19 patients: Nationwide clinical cohort study

BACKGROUND

Steroids are widely used to modulate the inflammatory reactions associated with coronavirus disease 2019 (COVID-19); however, the optimal upper limit dose of steroid use for acute COVID-19 care remains unclear and currently available data may suffer from a time-dependent bias of no effectiveness or reversed causation given the desperate situation of treatment during this pandemic. Accordingly, the aim of this study was to elucidate the impact of intravenous pulse therapy with methylprednisolone (500 mg or greater per day) on the risk of in-hospital mortality among patients with COVID-19 by controlling for time-dependent bias.

METHODS

We performed a prospective cohort study with 67,348 hospitalised acute COVID-19 patients at 438 hospitals during 2020-2021 in Japan. The impact of intravenous methylprednisolone pulse therapy on the risk of in-hospital mortality was examined based on hazard ratios (HRs) and 95% confidence intervals (95% CIs), with stratification according to the status of invasive mechanical ventilation (iMV). Time-dependent bias was controlled for in a marginal structural model analysis, with reference to patients without methylprednisolone therapy.

RESULTS

During the study period, 2400 patients died. In-hospital mortality rates of iMV-free patients without or with methylprednisolone pulse therapy were 2.3% and 19.5%, and the corresponding values for iMV-receiving patients were 24.7% and 28.6%, respectively. The marginal structural model analysis showed that intravenous pulse therapy with methylprednisolone was associated with a lower risk of in-hospital mortality among patients receiving-iMV (HR 0.59; 95% CI 0.52-0.68). In contrast, pulse therapy with methylprednisolone increased the risk of in-hospital mortality among iMV-free patients (HR 3.38; 95% CI 3.02-3.79). The benefits of pulse therapy for iMV-receiving patients were greater than in those treated with intermediate/higher doses (40-250 mg intravenously) of methylprednisolone (HR 0.80; 95% CI 0.71-0.89).

CONCLUSION

The results of our study suggest that intravenous methylprednisolone showed dose-response efficiencies, and pulse therapy may benefit critically ill patients with acute COVID-19, such as those requiring iMV.

Associations of COVID-19 Symptoms with Omicron Subvariants BA.2 and BA.5, Host Status, and Clinical Outcomes: A Registry-Based Observational Study in Sapporo, Japan

Background

Previous SARS-CoV-2 infection and vaccination, coupled to rapid evolution of SARS-CoV-2 variants, have modified COVID-19 clinical manifestations. We characterized clinical symptoms of COVID-19 individuals in omicron BA.2 and BA.5 Japanese pandemic periods to identify omicron and subvariant associations between symptoms, immune status, and clinical outcomes.

Methods

Individuals registered in Sapporo's web-based COVID-19 information system entered 12 pre-selected symptoms, days since symptom onset, vaccination history, SARS-CoV-2 infection history, and background. Symptom frequencies, variables associated with symptoms, and symptoms associated with progression to severe disease were analysed.

Results

For all omicron-infected individuals, cough was the most common symptom (62.7%), followed by sore throat (60.7%), nasal discharge (44.3%), and fever (38.8%). Omicron BA.5 infection was associated with a higher symptom burden than BA.2 in vaccinated and unvaccinated individuals. Omicron breakthrough-infected individuals with ≥ 3 vaccinations or previous infection were less likely to exhibit systemic symptoms, but more likely to exhibit upper respiratory symptoms. Infected elderly individuals had lower odds for all symptoms, but, when symptoms were manifest, systemic symptoms were associated with an increased risk, whereas upper respiratory symptoms with a decreased risk, of severe disease.

Conclusion

Host immunological status, omicron subvariant, and age were associated with a spectrum of COVID-19 symptoms and outcomes. BA.5 produced a greater symptom burden than BA.2. Vaccination and prior infection mitigated systemic symptoms and improved outcomes, but increased upper respiratory tract symptom burden. Systemic, but not upper respiratory, symptoms in the elderly heralded severe disease.

Association of combustible cigarettes and heated tobacco products use with SARS-CoV-2 infection and severe COVID-19 in Japan: a JASTIS 2022 cross-sectional study

Insufficient evidence has been accumulated regarding associations of heated tobacco products (HTPs) use with coronavirus infection and severity of coronavirus disease 2019 (COVID-19), an ongoing pandemic. We conducted a cross-sectional study using data from an internet questionnaire administered in February 2022 to 30,130 individuals from the general Japanese population (age range, 16-81 years). Single users of HTPs and dual users of combustible cigarettes and HTPs comprised 5.2% and 7.3% of respondents, and 6.7% and 38.0% of those infected (n = 1117). Approximately 70% of infected dual users experienced severe disease. Single users of HTPs and dual users were more likely to be infected with coronavirus than never-users (adjusted odds ratio [aOR] = 1.65/4.66; 95% confidence interval [CI] 1.26-2.15/3.89-5.58). Regarding severity, former and current tobacco users (former/combustible cigarettes/HTPs: aOR = 1.88/3.17/1.90; 95%CI 1.11-3.19/1.77-5.67/1.01-3.59) were more likely to be administered oxygen than never-users, and dual users required oxygen administration the most (aOR = 4.15, 95%CI 2.70-6.36). Use of HTPs may increase risks of coronavirus infection and severe COVID-19. Our results provide an opportunity to consider the safety of tobacco products use, including HTPs, during the COVID-19 pandemic.

Influence of obesity on incidence of thrombosis and disease severity in patients with COVID-19: From the CLOT-COVID study

BACKGROUND

The influence of obesity on the development of thrombosis and severity of coronavirus disease 2019 (COVID-19) remains unclear.

METHOD

The CLOT-COVID study was a retrospective multicenter cohort study enrolling 2894 consecutive hospitalized patients with COVID-19 between April 2021 and September 2021 among 16 centers in Japan. The present study consisted of 2690 patients aged over 18 years with available body mass index (BMI), who were divided into an obesity group (BMI ≥30) (N = 457) and a non-obesity group (BMI <30) (N = 2233).

RESULTS

The obesity group showed more severe status of COVID-19 at admission compared with the non-obesity group. The incidence of thrombosis was not significantly different between the groups (obesity group: 2.6 % versus non-obesity group: 1.9 %, p = 0.39), while the incidence of a composite outcome of all-cause death, or requirement of mechanical ventilation or extracorporeal membrane oxygenation during hospitalization was significantly higher in the obesity group (20.1 % versus 15.0 %, p < 0.01). After adjusting confounders in the multivariable logistic regression model, the risk of obesity relative to non-obesity for thrombosis was not significant (adjusted OR, 1.39; 95 % CI, 0.68-2.84, p = 0.37), while the adjusted risk of obesity relative to non-obesity for the composite outcome was significant (adjusted OR, 1.85; 95 % CI, 1.39-2.47, p < 0.001).

CONCLUSIONS

In the present large-scale observational study, obesity was not significantly associated with the development of thrombosis during hospitalization; however, it was associated with severity of COVID-19.

Characteristics of hospitalized patients with COVID-19 during the first to fifth waves of infection: a report from the Japan COVID-19 Task Force

BACKGROUND

We aimed to elucidate differences in the characteristics of patients with coronavirus disease 2019 (COVID-19) requiring hospitalization in Japan, by COVID-19 waves, from conventional strains to the Delta variant.

METHODS

We used secondary data from a database and performed a retrospective cohort study that included 3261 patients aged ≥ 18 years enrolled from 78 hospitals that participated in the Japan COVID-19 Task Force between February 2020 and September 2021.

RESULTS

Patients hospitalized during the second (mean age, 53.2 years [standard deviation {SD}, ± 18.9]) and fifth (mean age, 50.7 years [SD ± 13.9]) COVID-19 waves had a lower mean age than those hospitalized during the other COVID-19 waves. Patients hospitalized during the first COVID-19 wave had a longer hospital stay (mean, 30.3 days [SD ± 21.5], p < 0.0001), and post-hospitalization complications, such as bacterial infections (21.3%, p < 0.0001), were also noticeable. In addition, there was an increase in the use of drugs such as remdesivir/baricitinib/tocilizumab/steroids during the latter COVID-19 waves. In the fifth COVID-19 wave, patients exhibited a greater number of presenting symptoms, and a higher percentage of patients required oxygen therapy at the time of admission. However, the percentage of patients requiring invasive mechanical ventilation was the highest in the first COVID-19 wave and the mortality rate was the highest in the third COVID-19 wave.

CONCLUSIONS

We identified differences in clinical characteristics of hospitalized patients with COVID-19 in each COVID-19 wave up to the fifth COVID-19 wave in Japan. The fifth COVID-19 wave was associated with greater disease severity on admission, the third COVID-19 wave had the highest mortality rate, and the first COVID-19 wave had the highest percentage of patients requiring mechanical ventilation.