Significant Impact of Age on Mortality and Non-significant Impact of Age on Thrombosis and Major Bleeding in Patients with COVID-19: From the CLOT-COVID Study.

AIM: There is scarce data on the impact of age on clinical outcomes in patients with coronavirus disease 2019 (COVID-19). METHOD: The CLOT-COVID Study was a retrospective, multicenter cohort study enrolling 2894 consecutive hospitalized patients with COVID-19 among 16 centers in Japan from April 2021 to September 2021. We divided the entire cohort into five groups according to age strata; -19, 20-39, 40-59, 60-79, and 80- years. RESULTS: Most patients under 19 had mild COVID-19 on admission (99%), while older patients had more severe COVID-19. The incidence rates of clinical outcomes during hospitalization in patients aged ≤ 19, 20-39, 40-59, 60-79, and 80 ≥ years were 0.0%, 0.5%, 2.2%, 2.7%, and 1.5% for thrombosis; 0.0%, 1.2%, 1.5%, 3.4%, and 2.0% for major bleeding; and 0.0%, 0.4%, 2.0%, 12.1%, and 16.8% for all-cause death, respectively. In the stratified analysis according to COVID-19 severity on admission, the incidences of thrombosis were generally higher among patients with more severe status, although those were not significantly different among age strata in all sub-types of COVID-19 severity. However, the incidences of all-cause death were significantly higher with increasing age in all sub-types of COVID-19 severity. CONCLUSIONS: In the current large observational study of patients with COVID-19, the risk of mortality became markedly higher with increased age. However, the risks of thrombosis and major bleeding did not necessarily increase as age increases, which seemed to be consistent irrespective of COVID-19 severity on admission

The current status of thrombosis and anticoagulation therapy in patients with COVID-19 in Japan: From the CLOT-COVID study

BACKGROUND: Data on thrombosis and current real-world management strategies for anticoagulation therapy are scarce but important for understanding current issues and unmet needs of an optimal management of patients with coronavirus disease 2019 (COVID-19). METHOD: The CLOT-COVID Study (thrombosis and antiCoaguLatiOn Therapy in patients with COVID-19 in Japan Study: UMIN000045800) was a retrospective, multicenter cohort study enrolling consecutive hospitalized patients with COVID-19 among 16 centers in Japan from April 2021 to September 2021, and we tried to capture the status of the patients in the fourth and fifth waves of the COVID-19 infections in Japan. We enrolled consecutive hospitalized patients who were diagnosed with COVID-19 and had a positive polymerase chain reaction test obtained from the hospital databases. RESULTS: Among 2894 patients with COVID-19, 1245 (43%) received pharmacological thromboprophylaxis. The proportion of pharmacological thromboprophylaxis increased according to the severity of the COVID-19 in 9.8% with mild COVID-19, 61% with moderate COVID-19, and 97% with severe COVID-19. The types and doses of anticoagulants varied widely across the participating centers. During the hospitalization, 38 patients (1.3%) and 126 (4.4%) underwent ultrasound examinations for the lower extremities and contrast-enhanced computed tomography examinations, respectively, and 55 (1.9%) developed thrombosis, mostly venous thromboembolism (71%). The incidence of thrombosis increased according to the severity of the COVID-19 in 0.2% with mild COVID-19, 1.4% with moderate COVID-19, and 9.5% with severe COVID-19. Major bleeding occurred in 57 patients (2.0%) and 158 (5.5%) died, and 81% of them were due to respiratory failure from COVID-19 pneumonia. CONCLUSIONS: In the present large-scale observational study, pharmacological thromboprophylaxis for hospitalized patients with COVID-19 was common especially in patients with severe COVID-19, and management strategies varied widely across the participating centers. The overall incidence of thrombosis was substantially low with an increased incidence according to the severity of the COVID-19

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND: Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori. OBJECTIVES: To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started. SEARCH METHODS: We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively. SELECTION CRITERIA: We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as13C or14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities. MAIN RESULTS: We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons. AUTHORS' CONCLUSIONS: In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions

Therapeutic-Dose vs. Prophylactic-Dose Anticoagulation Therapy for Critically Ill Patients With COVID-19 in a Practice-Based Observational Study

BACKGROUND: The potential benefit of therapeutic-dose anticoagulation for critically ill patients with coronavirus disease 2019 (COVID-19) is still controversial.Methods and Results: In the CLOT-COVID study, 225 patients with severe COVID-19 on admission requiring mechanical ventilation or extracorporeal membrane oxygenation were divided into patients with therapeutic-dose anticoagulation (N=110) and those with prophylactic-dose anticoagulation (N=115). There was no significant difference in the incidence of thrombosis between the groups (9.1% vs. 7.8%, P=0.73). CONCLUSIONS: Among a cohort of critically ill patients with COVID-19, approximately half received therapeutic-dose anticoagulation, although it did not show a potential benefit compared with prophylactic-dose anticoagulation

Incidence and Clinical Features of Venous Thromboembolism in Hospitalized Patients With Coronavirus Disease 2019 (COVID-19) in Japan

BACKGROUND: Coronavirus disease 2019 (COVID-19) reportedly causes venous thromboembolism (VTE), but the status of this complication in Japan was unclear.Methods and Results:The VTE and COVID-19 in Japan Study is a retrospective, multicenter cohort study enrolling hospitalized patients with COVID-19 who were evaluated with contrast-enhanced computed tomography (CT) examination at 22 centers in Japan between March 2020 and October 2020. Among 1, 236 patients with COVID-19, 45 (3.6%) were evaluated with contrast-enhanced CT examination. VTE events occurred in 10 patients (22.2%), and the incidence of VTE in mild, moderate, and severe COVID-19 was 0%, 11.8%, and 40.0%, respectively. COVID-19 patients with VTE showed a higher body weight (81.6 vs. 64.0 kg, P=0.005) and body mass index (26.9 vs. 23.2 kg/m2, P=0.04), and a higher proportion had a severe status for COVID-19 compared with those without. There was no significant difference in the proportion of patients alive at discharge between patients with and without VTE (80.0% vs. 88.6%, P=0.48). Among 8 pulmonary embolism (PE) patients, all were low-risk PE. CONCLUSIONS: Among a relatively small number of patients undergoing contrast-enhanced CT examination in Japanese real-world clinical practice, there were no VTE patients among those with mild COVID-19, but the incidence of VTE seemed to be relatively high among severe COVID-19 patients, although all PE events were low-risk without significant effect on mortality risk

Incidence, risk factors, and clinical impact of major bleeding in hospitalized patients with COVID-19 : a sub-analysis of the CLOT-COVID Study

Background The coronavirus disease 2019 (COVID-19) causes extensive coagulopathy and a potential benefit of anticoagulation therapy has been documented for prevention of thromboembolic events. Bleeding events has also been reported as a notable complication; whereas, the incidence, risks, and clinical impact of bleeding remain unclear. Method The CLOT-COVID Study was a nationwide, retrospective, multicenter cohort study on consecutive hospitalized patients with COVID-19 in Japan between April 2021 and September 2021. In this sub-analysis, we compared the characteristics of patients with and without major bleeding; moreover, we examined the risk factors for and clinical impact of bleeding events. Results Among 2882 patients with COVID-19, 57 (2.0%) had major bleeding. The incidence of major bleeding increased with COVID-19 severity as follows: 0.5%, 2.3%, and 12.3% in patients with mild, moderate, and severe COVID-19, respectively. COVID-19 severity, history of major bleeding, and anticoagulant type/dose were independently and additively associated with the bleeding incidence. Compared with patients without major bleeding, those with major bleeding exhibited a longer duration of hospitalization (9 [6-14] vs 28 [19-43] days, P < 0.001) and higher mortality during hospitalization (4.9% vs. 35.1%, P < 0.001). Conclusions In the real-world clinical practice, the incidence of major bleeding was not uncommon, especially in patients with severe COVID-19. Independent risk factors for major bleeding included history of major bleeding, COVID-19 severity, and anticoagulant use, which could be associated with poor clinical outcomes including higher mortality. Precise recognition of the risks for bleeding may be helpful for an optimal use of anticoagulants and for better outcomes in patients with COVID-19