20 research outputs found
Infinite time blow-up for the three dimensional energy critical heat equation in bounded domains
We consider the Dirichlet problem for the energy-critical heat equation
\begin{equation*} \begin{cases} u_t=\Delta u+u^5,~&\mbox{ in } \Omega \times
\mathbb{R}^+,\\ u(x,t)=0,~&\mbox{ on } \partial \Omega \times \mathbb{R}^+,\\
u(x,0)=u_0(x),~&\mbox{ in } \Omega, \end{cases} \end{equation*} where
is a bounded smooth domain in . Let be the
regular part of the Green function of in , where
and is the first Dirichlet eigenvalue of
. Then, given a point such that ,
where we prove the
existence of a non-radial global positive and smooth solution which
blows up in infinite time with spike in . The solution has the asymptotic
profile where Comment: 74 pages, 1 figur
Hemorrhagic transformation in acute ischemic stroke patients and atrial fibrillation: time to initiation of anticoagulants and outcome
Background:
In patients with acute ischemic stroke and atrial fibrillation, early anticoagulation prevents ischemic recurrence but with the risk of hemorrhagic transformation (HT). The aims of this study were to evaluate in consecutive patients with acute stroke and atrial fibrillation (1) the incidence of early HT, (2) the time to initiation of anticoagulation in patients with HT, (3) the association of HT with ischemic recurrences, and (4) the association of HT with clinical outcome at 90 days.
Methods and Results:
HT was diagnosed by a second brain computed tomographic scan performed 24 to 72 hours after stroke onset. The incidence of ischemic recurrences as well as mortality or disability (modified Rankin Scale scores >2) were evaluated at 90 days. Ischemic recurrences were the composite of ischemic stroke, transient ischemic attack, or systemic embolism. Among the 2183 patients included in the study, 241 (11.0%) had HT. Patients with and without HT initiated anticoagulant therapy after a mean 23.3 and 11.6 days, respectively, from index stroke. At 90 days, 4.6% (95% confidence interval, 2.3â8.0) of the patients with HT had ischemic recurrences compared with 4.9% (95% confidence interval, 4.0â6.0) of those without HT; 53.1% of patients with HT were deceased or disabled compared with 35.8% of those without HT. On multivariable analysis, HT was associated with mortality or disability (odds ratio, 1.71; 95% confidence interval, 1.24â2.35).
Conclusions:
In patients with HT, anticoagulation was initiated about 12 days later than patients without HT. This delay was not associated with increased detection of ischemic recurrence. HT was associated with increased mortality or disability
Use of hydroxychloroquine in hospitalised COVID-19 patients is associated with reduced mortality: Findings from the observational multicentre Italian CORIST study
Background: Hydroxychloroquine (HCQ) was proposed as potential treatment for COVID-19. Objective: We set-up a multicenter Italian collaboration to investigate the relationship between HCQ therapy and COVID-19 in-hospital mortality. Methods: In a retrospective observational study, 3,451 unselected patients hospitalized in 33 clinical centers in Italy, from February 19, 2020 to May 23, 2020, with laboratory-confirmed SARS-CoV-2 infection, were analyzed. The primary end-point in a time-to event analysis was in-hospital death, comparing patients who received HCQ with patients who did not. We used multivariable Cox proportional-hazards regression models with inverse probability for treatment weighting by propensity scores, with the addition of subgroup analyses. Results: Out of 3,451 COVID-19 patients, 76.3% received HCQ. Death rates (per 1,000 person-days) for patients receiving or not HCQ were 8.9 and 15.7, respectively. After adjustment for propensity scores, we found 30% lower risk of death in patients receiving HCQ (HR=0.70; 95%CI: 0.59 to 0.84; E-value=1.67). Secondary analyses yielded similar results. The inverse association of HCQ with inpatient mortality was particularly evident in patients having elevated C-reactive protein at entry. Conclusions: HCQ use was associated with a 30% lower risk of death in COVID-19 hospitalized patients. Within the limits of an observational study and awaiting results from randomized controlled trials, these data do not discourage the use of HCQ in inpatients with COVID-19
Lopinavir/Ritonavir and Darunavir/Cobicistat in Hospitalized COVID-19 Patients: Findings From the Multicenter Italian CORIST Study
Background: Protease inhibitors have been considered as possible therapeutic agents for COVID-19 patients. Objectives: To describe the association between lopinavir/ritonavir (LPV/r) or darunavir/cobicistat (DRV/c) use and in-hospital mortality in COVID-19 patients. Study Design: Multicenter observational study of COVID-19 patients admitted in 33 Italian hospitals. Medications, preexisting conditions, clinical measures, and outcomes were extracted from medical records. Patients were retrospectively divided in three groups, according to use of LPV/r, DRV/c or none of them. Primary outcome in a time-to event analysis was death. We used Cox proportional-hazards models with inverse probability of treatment weighting by multinomial propensity scores. Results: Out of 3,451 patients, 33.3% LPV/r and 13.9% received DRV/c. Patients receiving LPV/r or DRV/c were more likely younger, men, had higher C-reactive protein levels while less likely had hypertension, cardiovascular, pulmonary or kidney disease. After adjustment for propensity scores, LPV/r use was not associated with mortality (HR = 0.94, 95% CI 0.78 to 1.13), whereas treatment with DRV/c was associated with a higher death risk (HR = 1.89, 1.53 to 2.34, E-value = 2.43). This increased risk was more marked in women, in elderly, in patients with higher severity of COVID-19 and in patients receiving other COVID-19 drugs. Conclusions: In a large cohort of Italian patients hospitalized for COVID-19 in a real-life setting, the use of LPV/r treatment did not change death rate, while DRV/c was associated with increased mortality. Within the limits of an observational study, these data do not support the use of LPV/r or DRV/c in COVID-19 patients
Low inâhospital mortality rate in patients with COVIDâ19 receiving thromboprophylaxis: data from the multicentre observational STARTâCOVID Register
Abstract
COVID-19 infection causes respiratory pathology with severe interstitial pneumonia and extra-pulmonary complications; in particular, it may predispose to thromboembolic disease. The current guidelines recommend the use of thromboprophylaxis in patients with COVID-19, however, the optimal heparin dosage treatment is not well-established. We conducted a multicentre,
Italian, retrospective, observational study on COVID-19 patients admitted to ordinary wards, to describe clinical characteristic of patients at admission, bleeding and thrombotic events occurring during hospital stay. The strategies used for thromboprophylaxis and its role on patient outcome were, also, described. 1091 patients hospitalized were included in
the START-COVID-19 Register. During hospital stay, 769 (70.7%) patients were treated with antithrombotic drugs: low molecular weight heparin (the great majority enoxaparin), fondaparinux, or unfractioned heparin. These patients were more frequently affected by comorbidities, such as hypertension, atrial fibrillation, previous thromboembolism, neurological disease,and cancer with respect to patients who did not receive thromboprophylaxis. During hospital stay, 1.2% patients had a major bleeding event. All patients were treated with antithrombotic drugs; 5.4%, had venous thromboembolism [30.5% deep vein thrombosis (DVT), 66.1% pulmonary embolism (PE), and 3.4% patients had DVT + PE]. In our cohort the mortality rate
was 18.3%. Heparin use was independently associated with survival in patients aged â„ 59 years at multivariable analysis. We confirmed the high mortality rate of COVID-19 in hospitalized patients in ordinary wards. Treatment with antithrombotic drugs is significantly associated with a reduction of mortality rates especially in patients older than 59 years
Splanchnic vein thrombosis-related mortality in the Veneto region (Italy), 2008â2019: Retrospective analysis of epidemiological data
BACKGROUND
Splanchnic vein thrombosis (SVT) is an uncommon manifestation of venous thromboembolism. Epidemiological data on SVT-related mortality rate is not available to date.
METHODS
We investigated time trends in SVT-related mortality rate, 2008-2019, in Veneto, an Italian high-income region of approximatively 5,000,000 inhabitants. SVT-related deaths were identified by the following ICD-10 codes: I81 (portal vein thrombosis), K75.1 (phlebitis of portal vein), K76.3 (liver infarction), K76.5 (hepatic veno-occlusive disease) or I82.0 (Budd-Chiari syndrome).
RESULTS
During the study period, a total of 557,932 deaths were recorded. SVT was reported in 823 cases; 776 (94%) consisted of portal vein thrombosis. The age-standardized SVT-related mortality rate varied from 1.47 (year 2008) to 1.52 (year 2019) per 100,000 person-years. An increase in the cause-specific annual mortality rate was observed in women (0.56 in 2008 to 1.04 per 100,000 person-years in 2019; average annual percent change +5.7%, 95%CI +3.1; +8.3%). In men, the cause-specific mortality rate moved from 2.53 in 2008 to 2.03 per 100,000 person-years in 2019 (average annual percent change -1.2%, 95%CI -4.0; +1.6%). After conditioning for age and sex, the odds of having a concomitant liver disease were higher for SVT-related deaths (OR 31.6; 95%CI 17.1-37.0) compared with non-SVT-related deaths. This also applies to gastrointestinal cancers (OR 1.28; 95%CI 1.07-1.55), although to a lesser extent.
CONCLUSIONS
We report first epidemiological estimates of SVT-related mortality in a Western country. These values will serve as a reference to weight novel potential factors associated with SVT-related death and interpret them from an epidemiological perspective
Global reporting of pulmonary embolism-related deaths in the World Health Organization mortality database: Vital registration data from 123Â countries.
Introduction
Pulmonary embolism (PE) has not been accounted for as a cause of death contributing to cause-specific mortality in global reports.
Methods
We analyzed global PE-related mortality by focusing on the latest year available for each member state in the World Health Organization (WHO) mortality database, which provides age-sex-specific aggregated mortality data transmitted by national authorities for each underlying cause of death. PE-related deaths were defined by International Classification of Diseases, Tenth Revision codes for acute PE or nonfatal manifestations of venous thromboembolism (VTE). The 2001 WHO standard population served for standardization.
Results
We obtained data from 123 countries covering a total population of 2Â 602Â 561Â 422. Overall, 50 (40.6%) were European, 39 (31.7%) American, 13 (10.6%) Eastern Mediterranean, 13 (10.6%) Western Pacific, 3 (2.4%) Southeast Asian, and 2 (1.6%) African. Of 116 countries classifiable according to population income, 57 (49.1%) were high income, 42 (36.2%) upper-middle income, 14 (12.1%) lower-middle income, and 3 (2.6%) low income. A total of 18Â 726Â 382 deaths were recorded, of which 86Â 930 (0.46%) were attributed to PE. PE-related mortality rate increased with age in most countries. The reporting of PE-related deaths was heterogeneous, with an age-standardized mortality rate ranging from 0 to 24 deaths per 100Â 000 population-years. Income status only partially explained this heterogeneity.
Conclusions
Reporting of PE-related mortality in official national vital registration was characterized by extreme heterogeneity across countries. These findings mandate enhanced efforts toward systematic and uniform coverage of PE-related mortality and provides a case for full recognition of PE and VTE as a primary cause of death
Recanalization rate in patients with proximal vein thrombosis treated with the direct oral anticoagulants
Background The recanalization rate in patients with deep venous thrombosis (DVT) of the legs treated with the direct oral anticoagulants (DOAC) is unknown. Methods In an Italian cohort, we investigated the rate of residual vein thrombosis (RVT) after three and/or six months in 352 patients with proximal DVT who had been treated with the DOACs as a stand-alone therapy or lead-in parenteral anticoagulants, and compared it to that recorded in a historical cohort of 1094 patients in which vitamin K antagonists (VKAs) had been employed. In both cohorts, RVT was defined as the ultrasound persistence of thrombotic material resulting in a diameter of at least 4 mm of incompressibility of the proximal veins. Results RVT was detected in 143 patients treated with DOACs (41.2%) after three months and in 58 patients (21.1%) after six months; the corresponding figure in patients treated with conventional anticoagulation was 52.3% and 54.5%, respectively. After adjusting for the baseline characteristics, the odds ratio of RVT in patients treated with the DOACs as compared with those treated with conventional anticoagulation was 0.63 (95% CI, 0.48\u20130.81) after three months, and 0.17 (95% CI; 0.11\u20130.26) after six months. Conclusions In patients with proximal DVT treated with the DOACs, the persistence of ultrasound detectable RVT is likely to occur less frequently than in patients treated with conventional anticoagulation. These results may have implications for the prognosis of patients with DVT
Hemorrhagic Transformation in Patients With Acute Ischemic Stroke and Atrial Fibrillation : Time to Initiation of Oral Anticoagulant Therapy and Outcomes
Background-In patients with acute ischemic stroke and atrial fibrillation, early anticoagulation prevents ischemic recurrence but with the risk of hemorrhagic transformation (HT). The aims of this study were to evaluate in consecutive patients with acute stroke and atrial fibrillation (1) the incidence of early HT, (2) the time to initiation of anticoagulation in patients with HT, (3) the association of HT with ischemic recurrences, and (4) the association of HT with clinical outcome at 90 days. Methods and Results-HT was diagnosed by a second brain computed tomographic scan performed 24 to 72 hours after stroke onset. The incidence of ischemic recurrences as well as mortality or disability (modified Rankin Scale scores > 2) were evaluated at 90 days. Ischemic recurrences were the composite of ischemic stroke, transient ischemic attack, or systemic embolism. Among the 2183 patients included in the study, 241 (11.0%) had HT. Patients with and without HT initiated anticoagulant therapy after a mean 23.3 and 11.6 days, respectively, from index stroke. At 90 days, 4.6% (95% confidence interval, 2.3-8.0) of the patients with HT had ischemic recurrences compared with 4.9% (95% confidence interval, 4.0-6.0) of those without HT; 53.1% of patients with HT were deceased or disabled compared with 35.8% of those without HT. On multivariable analysis, HT was associated with mortality or disability (odds ratio, 1.71; 95% confidence interval, 1.24-2.35). Conclusions-In patients with HT, anticoagulation was initiated about 12 days later than patients without HT. This delay was not associated with increased detection of ischemic recurrence. HT was associated with increased mortality or disability.Peer reviewe