Effects of low molecular weight heparin and fondaparinux on mortality, hemorrhagic and thrombotic complications in COVID-19 patients.

Background: Coronavirus disease 2019 (COVID-19) is associated with increased thrombosis prevalence. However, there are insufficient data supporting the appropriate anticoagulation dose in COVID-19. Objective: We aim to systematically assess the currently available data regarding the effects of different dosing regimens of low molecular weight heparin and/or fondaparinux (LMWH/F) on mortality risk as well as the risk of arterial/venous thrombotic events and hemorrhagic complications in confirmed COVID-19 cases. Design: We conducted a living systematic review and meta-analysis on the effects of different LMWH/F doses on mortality, thrombotic and hemorrhagic events in COVID-19 patients. Data Sources and Methods: MEDLINE, Scopus, Embase, Cochrane Library, Cochrane COVID-19 study register, European Union Drug Regulating Authorities Clinical Trials Database, and ClinicalTrials.gov were searched to detect observational cohort studies and randomized-controlled clinical trials (RCTs) comparing difference doses of LMWH/F among confirmed COVID-19 cases. Results: Thirty-one eligible studies (6 RCTs and 25 cohort studies) with 11,430 hospitalized patients were included. No association was found between LMWH/F and mortality during the following comparisons: (1) no LMWH/F versus any LMWH/F; (2) prophylactic versus higher than prophylactic LMWH/F; (3) prophylactic versus therapeutic LMWH/F; (4) intermediate versus therapeutic LMWH/F; and (5) lower than therapeutic versus therapeutic LMWH/F. Mortality was higher in patients receiving prophylactic versus intermediate LMWH/F (OR = 2.01; 95% CI: 1.19-3.39). However, this effect was mostly driven by observational data. No associations were detected between the intensity of LMWH/F and the risk of thrombotic and hemorrhagic events, except the lower risk for hemorrhage in patients on prophylactic compared to higher LMWH/F doses. Conclusion: The risk for all-cause mortality was higher in patients receiving prophylactic LMWH/F compared to those on an intermediate dose of LMWH/F, based on observational data. These results should be interpreted in light of the moderate quality and heterogeneity of the included studies. Registration: The study protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO (Registration number: CRD42021229771).

Cerebral venous sinus thrombosis in the setting of COVID-19 vaccination: a systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Cerebral venous sinus thrombosis (CVST) has been reported as a rare adverse event in association with thrombosis-thrombocytopenia syndrome (TTS) following COVID-19 vaccination. METHODS:  We performed a systematic review and meta-analysis of investigator-initiated registries including confirmed CVST cases, with the aim to calculate (1) the odds ratio of TTS-CVST versus non-TTS-CVST after vector-based vaccines and (2) after non-vector-based vaccines, (3) the in-hospital mortality ratio of TTS-CVST compared to non-TTS-CVST; and (4) the dependency or death at discharge among TTS-CVST compared to non-TTS-CVST cases. RESULTS: Two eligible studies were included in the meta-analysis, comprising a total of 211 patients with CVST associated with COVID-19 vaccination. Vector-based COVID-19 vaccination was associated with a higher likelihood of TTS-associated CVST than with non-TTS-CVST (OR: 52.34, 95% CI 9.58-285.98). TTS-CVST was also associated with higher likelihood of in-hospital mortality (OR: 13.29; 95% CI 3.96-44.60) and death or dependency at discharge compared to non-TTS-CVST (OR: 6.70; 95% CI 3.15-14.26). TTS-CVST was recorded with a shorter interval between vaccination and symptom onset [Mean Difference (MD):-6.54 days; 95% CI - 12.64 to - 0.45], affecting younger patients (MD:-9.00 years; 95% CI - 14.02 to - 3.99) without risk factors for thromboses (OR:2.34; 95% CI 1.26-4.33), and was complicated more frequently with intracerebral hemorrhage (OR:3.60; 95% CI 1.31-9.87) and concomitant thromboses in other sites (OR:11.85; 95% CI 3.51-39.98) compared to non-TTS-CVST cases. CONCLUSIONS: TTS-CVST following COVID-19 vaccination has distinct risk factor profile, clinical phenotype and prognosis compared to non-TTS-CVST. Further epidemiological data are required to evaluate the impact of different treatment strategies on outcome of TTS-CVST cases following COVID-19 vaccination.

Cerebral Venous Sinus Thrombosis and Thrombotic Events After Vector-Based COVID-19 Vaccines: A Systematic Review and Meta-analysis.

BACKGROUND AND OBJECTIVES: There is accumulating evidence supporting an association between the thrombosis and thrombocytopenia syndrome (TTS) and adenovirus vector-based vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Yet TTS and TTS-associated cerebral venous sinus thrombosis (CVST) remain poorly characterized. We aim to systematically evaluate the proportion of CVST among TTS cases and assess its characteristics and outcomes. METHODS: We performed a systematic review and meta-analysis of clinical trials, cohorts, case series, and registry-based studies with the aim to assess (1) the pooled mortality rate of CVST, TTS-associated CVST, and TTS and (2) the pooled proportion of patients with CVST among patients with any thrombotic event and TTS. Secondary outcomes comprised clinical characteristics of patients with postvaccination thrombotic event. This meta-analysis is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was written according to the Meta-analysis of Observational Studies in Epidemiology proposal. RESULTS: Sixty-nine studies were included in the qualitative analysis comprising 370 patients with CVST out of 4,182 patients with any thrombotic event associated with SARS-CoV-2 vector-based vaccine administration. Twenty-three studies were included further in quantitative meta-analysis. Among TTS cases, the pooled proportion of CVST was 51% (95% confidence interval [CI] 36%-66%; I 2 = 61%). TTS was independently associated with a higher likelihood of CVST when compared to patients without TTS with thrombotic events after vaccination (odds ratio 13.8; 95% CI 2.0-97.3; I 2 = 78%). The pooled mortality rates of TTS and TTS-associated CVST were 28% (95% CI 21%-36%) and 38% (95% CI 27%-49%), respectively. Thrombotic complications developed within 2 weeks of exposure to vector-based SARS-CoV-2 vaccines (mean interval 10 days; 95% CI 8-12) and affected predominantly women (69%; 95% CI 60%-77%) under age 45, even in the absence of prothrombotic risk factors. DISCUSSION: Approximately half of patients with TTS present with CVST; almost one-third of patients with TTS do not survive. Further research is required to identify independent predictors of TTS following adenovirus vector-based vaccination. REGISTRATION INFORMATION: The prespecified study protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO (CRD42021250709).

Prevalence, clinical characteristics and outcomes of Guillain-Barré syndrome spectrum associated with COVID-19: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Mounting evidence supports an association between Guillain-Barré syndrome spectrum (GBSs) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, GBSs in the setting of coronavirus disease 2019 (COVID-19) remains poorly characterized, whilst GBSs prevalence amongst COVID-19 patients has not been previously systematically evaluated using a meta-analytical approach. METHODS: A systematic review and meta-analysis of observational cohort and case series studies reporting on the occurrence, clinical characteristics and outcomes of patients with COVID-19-associated GBSs was performed. A random-effects model was used to calculate pooled estimates and odds ratios (ORs) with corresponding 95% confidence intervals (CIs), compared to non-COVID-19, contemporary or historical GBSs patients. RESULTS: Eighteen eligible studies (11 cohorts, seven case series) were identified including a total of 136,746 COVID-19 patients. Amongst COVID-19 patients, including hospitalized and non-hospitalized cases, the pooled GBSs prevalence was 0.15‰ (95% CI 0%-0.49‰; I2  = 96%). Compared with non-infected contemporary or historical controls, patients with SARS-CoV-2 infection had increased odds for demyelinating GBSs subtypes (OR 3.27, 95% CI 1.32%-8.09%; I2  = 0%). In SARS-CoV-2-infected patients, olfactory or concomitant cranial nerve involvement was noted in 41.4% (95% CI 3.5%-60.4%; I2  = 46%) and 42.8% (95% CI 32.8%-53%; I2  = 0%) of the patients, respectively. Clinical outcomes including in-hospital mortality were comparable between COVID-19 GBSs patients and non-infected contemporary or historical GBSs controls. CONCLUSION: GBSs prevalence was estimated at 15 cases per 100,000 SARS-CoV-2 infections. COVID-19 appears to be associated with an increased likelihood of GBSs and with demyelinating GBSs variants in particular.

A Real-World Observational Study Examining the Impact of Aclidinium Bromide Therapy on the Quality of Life, Symptoms, and Activity Impairment of Patients with Chronic Obstructive Pulmonary Disease: The Greek ON-AIR Study.

Purpose: This multicenter, prospective, observational study aimed to supplement real-world evidence on the effects of aclidinium bromide on the quality of life (QoL), symptoms, and activity impairment of patients with COPD. Patients and Methods: Eligible patients were ≥40 years of age, newly initiated on aclidinium bromide as monotherapy or add-on therapy according to the product's approved label. Patient-reported COPD assessment test (CAT), the severity of symptoms and their impact on daily activities, and the features of the Genuair® inhaler device were assessed at enrollment and at 12 weeks post-treatment onset. Results: Between 13 March 2015 and 29 January 2016, 285 eligible consenting patients (76.3% males; median age: 69.0 years; 26.0% newly diagnosed with COPD) were enrolled by 15 hospital-based respiratory medicine specialists in Greece. Aclidinium bromide was initiated as add-on therapy to other inhaled maintenance medications in 73.1% of evaluable patients. The median (interquartile range [IQR]) baseline CAT score decreased from 14.0 (9.0-20.0) to 10.0 (6.0-15.0) points (p<0.001) after 12 weeks of treatment, with 76.5% of the patients achieving a ≥2-point decrease. The severity of night-time and early-morning symptoms, assessed using a 5-point Likert-type scale, decreased from a median (IQR) of 1.0 (0.0-2.0) to 0.0 (0.0-1.0), and from 2.0 (1.0-2.0) to 1.0 (1.0-2.0), respectively (p<0.001 for both). In patients with paired data, the prevalence of at least moderate night-time symptoms, early-morning symptoms, and daily activity impairment decreased from 28.2% to 19.1%, from 63.6% to 34.2%, and from 59.5% to 38.7%, respectively (p<0.001 for all). Inhaler device features were assessed as "very good"/"good" by more than 90% of the patients. The adverse drug reaction rate was 1.4%. Conclusion: The study provides real-world evidence on the beneficial effects of aclidinium bromide on the patients' QoL, symptom severity, and daily activity impairment, which are complemented by a favorable safety profile and high patient satisfaction with the inhaler device.