Messenger RNA Coronavirus Disease 2019 (COVID-19) Vaccination With BNT162b2 Increased Risk of Bell's Palsy: A Nested Case-Control and Self-Controlled Case Series Study.

BACKGROUND: Observable symptoms of Bell's palsy following vaccinations arouse concern over the safety profiles of novel coronavirus disease 2019 (COVID-19) vaccines. However, there are only inconclusive findings on Bell's palsy following messenger (mRNA) COVID-19 vaccination. This study aims to update the previous analyses on the risk of Bell's palsy following mRNA (BNT162b2) COVID-19 vaccination. METHODS: This study included cases aged ≥16 years with a new diagnosis of Bell's palsy within 28 days after BNT162b2 vaccinations from the population-based electronic health records in Hong Kong. Nested case-control and self-controlled case series (SCCS) analyses were used, where the association between Bell's palsy and BNT162b2 was evaluated using conditional logistic and Poisson regression, respectively. RESULTS: Totally 54 individuals were newly diagnosed with Bell's palsy after BNT162b2 vaccinations. The incidence of Bell's palsy was 1.58 (95% confidence interval [CI], 1.19-2.07) per 100 000 doses administered. The nested case-control analysis showed significant association between BNT162b2 vaccinations and Bell's palsy (adjusted odds ratio [aOR], 1.543; 95% CI, 1.123-2.121), with up to 1.112 excess events per 100 000 people who received 2 doses of BNT162b2. An increased risk of Bell's palsy was observed during the first 14 days after the second dose of BNT162b2 in both nested case-control (aOR, 2.325; 95% CI, 1.414-3.821) and SCCS analysis (adjusted incidence rate ratio, 2.44; 95% CI, 1.32-4.50). CONCLUSIONS: There was an overall increased risk of Bell's palsy following BNT162b2 vaccination, particularly within the first 14 days after the second dose, but the absolute risk was very low.

Plaque morphology in acute symptomatic intracranial atherosclerotic disease.

BACKGROUND: Intracranial atherosclerotic disease (ICAD) is globally a major ischaemic stroke subtype with high recurrence. Understanding the morphology of symptomatic ICAD plaques, largely unknown by far, may help identify vulnerable lesions prone to relapse. METHODS: We prospectively recruited patients with acute ischaemic stroke or transient ischaemic attack attributed to high-grade ICAD (60%-99% stenosis). Plaque morphological parameters were assessed in three-dimensional rotational angiography, including surface contour, luminal stenosis, plaque length/thickness, upstream shoulder angulation, axial/longitudinal plaque distribution and presence of adjoining branch atheromatous disease (BAD). We compared morphological features of smooth, irregular and ulcerative plaques and correlated them with cerebral ischaemic lesion load downstream in MRI. RESULTS: Among 180 recruited patients (median age=60 years; 63.3% male; median stenosis=75%), plaque contour was smooth (51 (28.3%)), irregular (101 (56.1%)) or ulcerative (28 (15.6%)). Surface ulcers were mostly at proximal (46.4%) and middle one-third (35.7%) of the lesions. Most (84.4%) plaques were eccentric, and half had their maximum thickness over the distal end. Ulcerative lesions were thicker (medians 1.6 vs 1.3 mm; p=0.003), had steeper upstream shoulder angulation (56.2° vs 31.0°; p<0.001) and more adjoining BAD (83.3% vs 57.0%; p=0.033) than non-ulcerative plaques. Ulcerative plaques were significantly associated with coexisting acute and chronic infarcts downstream (35.7% vs 12.5%; adjusted OR 4.29, 95% CI 1.65 to 11.14, p=0.003). Sensitivity analyses in patients with anterior-circulation ICAD lesions showed similar results in the associations between the plaque types and infarct load. CONCLUSIONS: Ulcerative intracranial atherosclerotic plaques were associated with vulnerable morphological features and had a higher cumulative infarct load downstream.

Risk of intracerebral haemorrhage in Chinese patients with atrial fibrillation on warfarin with cerebral microbleeds: the IPAAC-Warfarin study.

BACKGROUND AND PURPOSE: Cerebral microbleeds (CMBs), which predict future intracerebral haemorrhage (ICH), may guide anticoagulant decisions for atrial fibrillation (AF). We aimed to evaluate the risk of warfarin-associated ICH in Chinese patients with AF with CMBs. METHODS: In this prospective, observational, multicentre study, we recruited Chinese patients with AF who were on or intended to start anticoagulation with warfarin from six hospitals in Hong Kong. CMBs were evaluated with 3T MRI brain at baseline. Primary outcome was clinical ICH at 2-year follow-up. Secondary outcomes were ischaemic stroke, systemic embolism, mortality of all causes and modified Rankin Scale ≥3. Outcome events were compared between patients with and without CMBs. RESULTS: A total of 290 patients were recruited; 53 patients were excluded by predefined criteria. Among the 237 patients included in the final analysis, CMBs were observed in 84 (35.4%) patients, and 11 had ≥5 CMBs. The mean follow-up period was 22.4±10.3 months. Compared with patients without CMBs, patients with CMBs had numerically higher rate of ICH (3.6% vs 0.7%, p=0.129). The rate of ICH was lower than ischaemic stroke for patients with 0 to 4 CMBs, but higher for those with ≥5 CMBs. CMB count (C-index 0.82) was more sensitive than HAS-BLED (C-index 0.55) and CHA2DS2-VASc (C-index 0.63) scores in predicting ICH. CONCLUSIONS: In Chinese patients with AF on warfarin, presence of multiple CMBs may be associated with higher rate of ICH than ischaemic stroke. Larger studies through international collaboration are needed to determine the risk:benefit ratio of oral anticoagulants in patients with AF of different ethnic origins.

Evolution of intracranial atherosclerotic disease under modern medical therapy.

OBJECTIVE: Understanding how symptomatic intracranial atherosclerotic disease (ICAD) evolves with current medical therapy may inform secondary stroke prevention. METHODS: In a prospective academic-initiated study, we recruited 50 patients (mean age = 63.4 ± 9.0 years) with acute strokes attributed to high-grade (≥70%) intracranial atherosclerotic stenosis for 3-dimensional rotational angiograms before and after intensive medical therapy for 12 months. Treatment targets included low-density lipoprotein ≤ 70mg/dl, glycosylated hemoglobin (HbA1c) ≤ 6.5%, and systolic blood pressure ≤ 140 mmHg. We analyzed infarct topography and monitored microembolic signal in recurrent strokes. The reference group was a published cohort of 143 ICAD patients. RESULTS: Overall, the stenoses regressed from 79% at baseline (interquartile range [IQR] = 71-87%) to 63% (IQR = 54-74%) in 1 year (p < 0.001). Specifically, the qualifying lesions (n = 49) regressed (stenosis reduced >10%) in 24 patients (49%), remained quiescent (stenosis same or ±10%) in 21 patients (43%), and progressed (stenosis increased >10%) in 4 patients (8%). There was no difference in intensity of risk factor control between groups of diverging clinical or angiographic outcomes. Higher HbA1c at baseline predicted plaque regression at 1 year (odds ratio = 4.4, 95% confidence interval = 1.4-14.5, p = 0.006). Among the 6 patients with recurrent strokes pertaining to the qualifying stenosis, 5 patients had solitary or rosarylike acute infarcts along the internal or anterior border zones, and 2 patients showed microembolic signals in transcranial Doppler ultrasound. INTERPRETATION: A majority of symptomatic high-grade intracranial plaques had regressed or remained quiescent by 12 months under intensive medical therapy. Artery-to-artery thromboembolism with impaired washout at border zones was a common mechanism in stroke recurrence.

Telephone and Teleradiology-Guided Thrombolysis Can Achieve Similar Outcome as Thrombolysis by Neurologist On-site.

BACKGROUND: Because of the limitation of on-site neurology workforce, telestroke was implemented to overcome this barrier. We explored the efficacy and safety of intravenous (IV) stroke thrombolysis service by telestroke when neurologist was not available on-site. METHODS: From January 2009 to December 2012, we compared patients treated with IV stroke thrombolysis by telestroke in the form of telephone consultation with teleradiology, to patients treated after in-person assessment by the same team of neurologists in a regional hospital. Door-to-needle time, symptomatic intracranial hemorrhage, and functional outcome at 3 months were prospectively collected and compared between the groups. RESULTS: In all, 152 patients were treated with IV thrombolysis; 102 patients were treated with neurologist on-site; whereas 50 patients were treated by internists with telestroke. Fifty-two percent of the telemedical group achieved excellent outcome compared to 43% of the neurologist on-site group (P = .30). Symptomatic intracranial hemorrhage rate (4.0% versus 4.9%, P = 1.0) and mortality (8.3% versus 11.9%, P = .49) were comparable. Using the multiple logistic regression analysis, age, baseline stroke severity, and extent of early ischemic change on brain computed tomography scan, are independent predictors for excellent outcome, whereas the presence of neurologist on-site is not correlated with the outcome. CONCLUSIONS: Patients treated without neurologist on-site achieved similar outcome. Telephone consultation and teleradiology-guided IV stroke thrombolysis, with the support of on-site internist appeared safe and efficacious.

Development and validation of the Chinese oral anticoagulants knowledge tool (C-OAKT): A pilot study.

Objective: To develop and validate an oral anticoagulant knowledge tool for Chinese-speaking patients treated with warfarin or direct oral anticoagulants (DOACs) in Hong Kong. Method: This pilot validation study consisted of the following three phases: (1) the development of a knowledge tool and content validity assessment; (2) a pilot study of 200 participants, consisting of 100 patients taking warfarin or DOACs, 50 pharmacists, and 50 members of the general public; and (3) known-group validity and reliability assessments. Results: A 19-item "Chinese Oral Anticoagulants Knowledge Tool (C-OAKT)" was developed with a scale content validity index of 0.95. The mean score for known-group validity was significantly higher in the pharmacist group than the patient groups, and the patient groups scored significantly higher than the general public (mean ± standard deviation [SD] = 90.00 ± 7.11 vs. 51.55 ± 17.49 vs. 19.0 ± 15.42, respectively; p < 0.001). The mean score was higher for patients who attended a pharmacist-managed anticoagulant therapy management clinic (PAC) than for non-PAC patients (mean ± SD = 56.80 ± 13.60 vs. 46.30 ± 9.43; p = 0.004). An analysis of internal consistency showed a Cronbach's alpha value of 0.86. Conclusion: The results of the pilot validation study suggested that the C-OAKT is a valid and reliable instrument for assessing patients' knowledge of oral anticoagulants in ambulatory care settings. Innovations: This is the first validated Chinese version of an anticoagulant knowledge assessment tool. This tool will be utilized in public hospitals in Hong Kong, and will facilitate future research exploring the relationship between anticoagulant knowledge and patient-related outcomes.

Bell's palsy following vaccination with mRNA (BNT162b2) and inactivated (CoronaVac) SARS-CoV-2 vaccines: a case series and nested case-control study.

BACKGROUND: Bell's palsy is a rare adverse event reported in clinical trials of COVID-19 vaccines. However, to our knowledge no population-based study has assessed the association between the inactivated SARS-CoV-2 vaccines and Bell's palsy. The aim of this study was to evaluate the risk of Bell's palsy after BNT162b2 and CoronaVac vaccination. METHODS: In this case series and nested case-control study done in Hong Kong, we assessed the risk of Bell's palsy within 42 days following vaccination with BNT162b2 (Fosun-BioNTech [equivalent to Pfizer-BioNTech]) or CoronaVac (from Sinovac Biotech, Hong Kong) using data from voluntary surveillance reporting with the Hospital Authority, the COVID-19 Vaccine Adverse Event Online Reporting system for all health-care professionals, and the Hospital Authority's territory-wide electronic health records from the Clinical Data Analysis and Reporting System. We described reported cases of Bell's palsy among vaccine recipients (aged 18-110 years for CoronaVac and aged 16-110 years for BNT162b2). We compared the estimated age-standardised incidence of clinically confirmed cases among individuals who had received the CoronaVac or BNT162b2 vaccination (up to 42 days before presentation) with the background incidence in the population. A nested case-control study was also done using conditional logistic regression to estimate the odds ratio (OR) for risk of Bell's palsy and vaccination. Cases and controls were matched (1:4) by age, sex, admission setting, and admission date. FINDINGS: Between February 23 and May 4, 2021, 451 939 individuals received the first dose of CoronaVac and 537 205 individuals received the first dose of BNT162b2. 28 clinically confirmed cases of Bell's palsy were reported following CoronaVac and 16 cases were reported following BNT162b2. The age-standardised incidence of clinically confirmed Bell's palsy was 66·9 cases per 100 000 person-years (95% CI 37·2 to 96·6) following CoronaVac vaccination and 42·8 per 100 000 person-years (19·4 to 66·1) for BNT162b2 vaccination. The age-standardised difference for the incidence compared with the background population was 41·5 (95% CI 11·7 to 71·4) for CoronaVac and 17·0 (-6·6 to 40·6) for BNT162b2, equivalent to an additional 4·8 cases per 100 000 people vaccinated for CoronaVac and 2·0 cases per 100 000 people vaccinated for BNT162b2. In the nested case-control analysis, 298 cases were matched to 1181 controls, and the adjusted ORs were 2·385 (95% CI 1·415 to 4·022) for CoronaVac and 1·755 (0·886 to 3·477) for BNT162b2. INTERPRETATION: Our findings suggest an overall increased risk of Bell's palsy after CoronaVac vaccination. However, the beneficial and protective effects of the inactivated COVID-19 vaccine far outweigh the risk of this generally self-limiting adverse event. Additional studies are needed in other regions to confirm our findings. FUNDING: The Food and Health Bureau of the Government of the Hong Kong Special Administrative Region, China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Low-molecular-weight heparin compared with aspirin for the treatment of acute ischaemic stroke in Asian patients with large artery occlusive disease: a randomised study.

BACKGROUND: Acute stroke patients with large artery occlusive disease (LAOD) have a distinct pathophysiology and may respond differently to anticoagulation treatments. We compared the efficacy of a low-molecular-weight heparin (LMWH), nadroparin calcium, with aspirin in Asian acute stroke patients with LAOD. METHODS: Acute ischaemic stroke patients with onset of symptoms less than 48 h and LAOD (diagnosed by transcranial doppler imaging, carotid duplex scan, or magnetic resonance angiography) were recruited. Patients were randomly assigned to receive either subcutaneous nadroparin calcium 3800 anti-factor Xa IU/0.4 mL twice daily or oral aspirin 160 mg daily for 10 days, and then all received aspirin 80-300 mg once daily for 6 months. This study is registered at www.strokecenter.org/trials (number 493). FINDINGS: Among 603 patients recruited, 353 (180 LMWH, 173 aspirin) had LAOD (300 had intracranial LAOD only, 42 had both intracranial and extracranial disease, and 11 had extracranial disease only). The proportion of patients with good outcomes at 6 months (Barthel index >or=85) was 73% in the LMWH group and 69% in the aspirin group (absolute risk reduction 4%; 95% CI -5 to 13). Analysis of prespecified secondary outcome measures showed a benefit in outcome for LMWH versus aspirin on the modified Rankin scale dichotomised at 0-1 (odds ratio 1.55, 95% CI 1.02-2.35). Haemorrhagic transformation of infarct and severe adverse events were similar in both groups. Post-hoc analyses of patients without LAOD, and all treated patients, showed similar proportions with a good outcome in aspirin and LMWH groups (78%vs 79% and 73%vs 75%, respectively). INTERPRETATION: Overall, the results do not support a significant benefit of LMWH over aspirin in patients with LAOD. The benefits indicated in most outcome measures warrant further investigation into the use of anticoagulation for acute stroke in patients with large artery atherosclerosis, particularly in intracranial atherosclerosis.

De novo status epilepticus is associated with adverse outcome: An 11-year retrospective study in Hong Kong.

PURPOSE: To identify predictors of poor clinical outcome in patients presenting to the intensive care units with status epilepticus (SE), in particular for patients presenting with de novo status epileptics. METHODS: A retrospective review was performed on patients admitted to the intensive care units with status epilepticus in two hospitals in Hong Kong over an 11-year period from 2003 to 2013. RESULTS: A total of 87 SE cases were analyzed. The mean age of patients was 49.3 years (SD 14.9 years). Eighteen subjects (20.7%) had breakthrough seizure, which was the most common etiology for the status epilepticus episodes. Seventy-eight subjects (89.7%) had convulsive status epilepticus (CSE) and 9 subjects (10.3%) had non-convulsive status epilepticus (NCSE) on presentation. The 30-day mortality rate of all subjects was 18.4%. Non-convulsive status epilepticus was more common in patients with de novo status epilepticus when compared to those with existing history of epilepsy (15.5% Vs. 0%, p=0.03). Patients with de novo status epilepticus were older (52 Vs 43, p=0.009). De novo status epilepticus was associated with longer status duration (median 2.5 days, IQR 5 days), longer ICU stay (median 7.5 days, IQR 9 days) and poorer outcome (OR 4.15, 95% CI 1.53-11.2). CONCLUSIONS: For patients presenting to intensive care units with status epilepticus, those with de novo status epileptics were older and were more likely to develop non-convulsive status epilepticus. De novo status epilepticus was associated with poorer outcome. Continuous EEG monitoring would help identifying NCSE and potentially help improving clinical outcomes.

Insular cortex infarction in acute middle cerebral artery territory stroke: predictor of stroke severity and vascular lesion.

BACKGROUND: Insula infarction is an early computed tomographic sign of middle cerebral artery (MCA) territory stroke and may affect cardiovascular autonomic function. OBJECTIVE: To determine insula involvement in MCA territory infarction and its relationship with infarcts in the remainder of the MCA territory, stroke severity, and clinically relevant cardiovascular conditions. DESIGN: Case series (August 1, 1997, to June 30, 2000). SETTING: Academic stroke center. PATIENTS: A total of 150 consecutive patients with nonlacunar MCA territory stroke who underwent magnetic resonance imaging within 48 hours of stroke onset. MAIN OUTCOME MEASURES: Association of insula infarction with the National Institutes of Health Stroke Scale (NIHSS) score, location of vascular occlusion, and cardiovascular events. RESULTS: Insular lesions were present in 72 patients (48%); 34 (23%) had major insular lesions and 38 (25%) had minor lesions. Insula infarction was associated with lenticulostriate territory infarction (46% vs 14%; P<.001), more than one third of MCA territory infarction (35% vs 3%; P<.001), higher NIHSS score (13.5 vs 6; P<.001), and proximal vascular occlusion detected on magnetic resonance angiography. These associations were strongest for patients with major insular lesions. Clinically significant new arrhythmia was present in 15 of 72 with insula infarction (13 atrial fibrillations) and 4 of 78 without (P = .06). Insula infarction was associated with lower diastolic blood pressure at admission but was not associated with pulse rate, QTc interval, myocardial infarction, or sudden death. CONCLUSIONS: The insular cortex is involved in almost half of patients with nonlacunar ischemic MCA territory strokes. Major insula involvement is associated with large MCA territory infarcts, proximal MCA occlusions, and greater stroke severity. Insula infarction was not a predictor of clinically significant acute cardiovascular events during hospital stay in our patients.

Thrombolysis in chinese ischemic stroke patients with renal dysfunction.

BACKGROUND: Current data concerning the relationship between renal function and clinical outcome among stroke patients treated with intravenous thrombolytic therapy are conflicting. Our aim is to analyze whether the clinical outcome of Chinese ischemic stroke patients treated with thrombolytic therapy is affected by the presence of renal dysfunction. METHODS: Chinese patients who received intravenous thrombolytic therapy for acute ischemic stroke were recruited. Renal dysfunction was defined as an estimated glomerular filtration rate (eGFR) <90 ml/min/1.73 m(2). The primary outcome was independent function (modified Rankin Scale, mRS, 0-2) at 3 months, while secondary outcomes included early improvement of the National Institute of Health Stroke Scale (NIHSS) score of ≥4 points at 24 h, symptomatic intracerebral hemorrhage (ICH) within 36 h of treatment and 30-day mortality. RESULTS: A total of 199 patients were recruited, of whom 51.3% had renal dysfunction. There were no significant differences in functional independence at 3 months, NIHSS improvement at 24 h post-thrombolysis and 30-day mortality between patients with or without renal dysfunction. Multivariate analysis showed that eGFR as a continuous variable was not an independent risk factor for symptomatic ICH. CONCLUSION: Chinese ischemic stroke patients with renal dysfunction who received thrombolytic therapy had clinical outcomes similar to those without renal dysfunction.

Short-Term Prognosis of Transient Ischemic Attack and Predictive Value of the ABCD(2) Score in Hong Kong Chinese.

BACKGROUND: Literature on prognosis of transient ischemic attack (TIA) in Chinese is scarce. The short-term prognosis of TIA and the predictive value of the ABCD(2) score in Hong Kong Chinese patients attending the emergency department (ED) were studied to provide reference for TIA patient management in our ED. METHODS: A cohort of TIA patients admitted through the ED to 13 acute public hospitals in 2006 was recruited through the centralized electronic database by the Hong Kong Hospital Authority (HA). All inpatients were e-coded by the HA according to the International Classification of Diseases, Ninth Revision (ICD9). Electronic records and hard copies were studied up to 90 days after a TIA. The stroke risk of a separate TIA cohort diagnosed by the ED was compared. RESULTS: In the 1,000 recruited patients, the stroke risk after a TIA at days 2, 7, 30, and 90 was 0.2, 1.4, 2.9, and 4.4%, respectively. Antiplatelet agents were prescribed in 89%, warfarin in 6.9%, statin in 28.6%, antihypertensives in 39.3%, and antidiabetics in 11.9% of patients after hospitalization. Before the index TIA, the prescribed medications were 27.6, 3.7, 11.3, 27.1, and 9.7%, respectively. The accuracy of the ABCD(2) score in predicting stroke risk was 0.607 at 7 days, 0.607 at 30 days, and 0.574 at 90 days. At 30 days, the p for trend across ABCD(2) score levels was 0.038 (OR for every score point = 1.36, p = 0.040). Diabetes mellitus, previous stroke and carotid bruit were associated with stroke within 90 days (p = 0.038, 0.045, 0.030, respectively). A total of 45.4% of CTs of the brain showed lacunar infarcts or small vessel disease. There was an increased stroke risk at 90 days in patients with old or new infarcts on CT or MRI. Patients with carotid stenosis ≥70% had an increased stroke risk within 30 (OR = 6.335, p = 0.013) and 90 days (OR = 3.623, p = 0.050). Stroke risks at days 2, 7, 30, and 90 in the 289 TIA patients diagnosed by the ED were 0.35, 2.4, 5.2, and 6.2%, respectively. CONCLUSION: The short-term stroke risk in Hong Kong Chinese TIA patients is low. The administered nonurgent treatment cannot solely explain the favorable outcome, the lower risk can be due to the different pathophysiological mechanisms of stroke between Caucasians and Chinese. The predictive value of the ABCD(2) score is low in our population.