Search

The risk of seizure following BNT162b2 and CoronaVac vaccinations has been sparsely investigated. This study aimed to evaluate this association.Patients who had their first seizure-related hospitalization between February 23, 2021 and January 31, 2022, were identified in Hong Kong. All seizure episodes happening on the day of vaccination (day 0) were excluded, since clinicians validated that most of the cases on day 0 were syncopal episodes. Within-individual comparison using a modified self-controlled case series analysis was applied to estimate the incidence rate ratio (IRR) with 95% confidence intervals (CIs) of seizure using conditional Poisson regression.We identified 1656 individuals who had their first seizure-related hospitalization (BNT162b2: 426; CoronaVac: 263; unvaccinated: 967) within the observation period. The incidence of seizure was 1.04 (95% CI .80-1.33) and 1.11 (95% CI .80-1.50) per 100 000 doses of BNT162b2 and CoronaVac administered, respectively. Sixteen and 17 individuals, respectively, received a second dose after having a first seizure within 28 days after the first dose of BNT162b2 and CoronaVac vaccinations. None had recurrent seizures after the second dose. There was no increased risk during day 1-6 after the first (BNT162b2: IRR = 1.39, 95% CI = .75-2.58; CoronaVac: IRR = 1.19, 95% CI = .50-2.83) and second doses (BNT162b2: IRR = 1.36, 95% CI = .72-2.57; CoronaVac: IRR = .71, 95% CI = .22-2.30) of vaccinations. During 7-13, 14-20, and 21-27 days post-vaccination, no association was observed for either vaccine.The findings demonstrated no increased risk of seizure following BNT162b2 and CoronaVac vaccinations. Future studies will be warranted to evaluate the risk of seizure following COVID-19 vaccinations in different populations, with subsequent doses to ensure the generalizability.

This study proposed a semisupervised loss function named level-set loss (LSLoss) for cerebral white matter hyperintensities (WMHs) segmentation on fluid-attenuated inversion recovery images. The training procedure did not require manually labeled WMH masks. Our image preprocessing steps included biased field correction, skull stripping, and white matter segmentation. With the proposed LSLoss, we trained a V-Net using the MRI images from both local and public databases. Local databases were the small vessel disease cohort (HKU-SVD, n = 360) and the multiple sclerosis cohort (HKU-MS, n = 20) from our institutional imaging center. Public databases were the Medical Image Computing Computer-assisted Intervention (MICCAI) WMH challenge database (MICCAI-WMH, n = 60) and the normal control cohort of the Alzheimer's Disease Neuroimaging Initiative database (ADNI-CN, n = 15). We achieved an overall dice similarity coefficient (DSC) of 0.81 on the HKU-SVD testing set (n = 20), DSC = 0.77 on the HKU-MS testing set (n = 5), and DSC = 0.78 on MICCAI-WMH testing set (n = 30). The segmentation results obtained by our semisupervised V-Net were comparable with the supervised methods and outperformed the unsupervised methods in the literature.

Direct-to-consumer genetic testing (DTCGT) is gaining popularity in Hong Kong (HK). As DTCGT forgoes specialist medical involvement, healthcare professionals have raised concerns regarding its validity, utility, and the public's ability to interpret DTCGT results. Thus, genetic counseling (GC) is recommended to facilitate understanding of DTCGT. This study aimed to investigate HK public's perception toward DTCGT and the importance of GC in DTCGT. A total of 304 HK adults were invited to complete a 37-item survey online. Participants' genomic literacy, understanding and attitude toward DTCGT and GC, and responses to a mock DTCGT scenario were assessed. 48% of participants were aware of DTCGT while 82% indicated an interest. 30% of participants were aware of GC services in HK; 49% were interested in GC services for understanding DTCGT results. Participants scored on average 7.6/11 in the genomic sequencing knowledge scale and were weak in limitations of genomic testing. In the mock DTCGT scenario, 73% of participants expressed concern with the positive results initially. After being explained limitations of DTCGT, 40% of participants reported decreased concern. Reduced perceived helpfulness in medical management and lifestyle modification were also reported by 35% and 27%, respectively. This HK population demonstrated a high level of awareness and interest in DTCGT. As potential DTCGT users, they might experience excess concern and overestimate the usefulness of positive DTCGT results, particularly in medical management. The importance of GC to educate and guide interpretation of DTCGT results is supported; yet the awareness and access of GC services is inadequate in HK.

BACKGROUND: Underlying mechanisms of PR‐interval prolongation leading to increased risk of adverse cardiovascular outcomes, including atrial fibrillation, are unclear. This study aims to investigate the relation between PR interval and changes in vascular function. HYPOTHESIS: We hypothesize that there exists an intermediate pathological stage between electrocardiographic PR prolongation and adverse cardiovascular outcomes, which could be reflected by changes in surrogate measurements of vascular function. METHODS: We recruited 88 healthy subjects (mean age 57.5 ± 9.8 y, 46% male) from a community‐based health screening program who had no history of cardiovascular disease or diabetes mellitus. PR interval was determined from a resting 12‐lead electrocardiogram. Vascular function was noninvasively assessed by flow‐mediated dilation (FMD) using high‐resolution ultrasound and brachial‐ankle pulse wave velocity (PWV) using a vascular profiling system. RESULTS: Only 3 subjects had a PR‐interval length longer than the conventional cutoff of 200 ms. The PR‐interval length was associated inversely with FMD (Pearson r = −0.30, P = 0.004) and positively with PWV (r = 0.40, P < 0.001). Adjusting for potential confounders, increased PR‐interval length by each 25 ms was independently associated with reduced FMD by −1 unit (absolute %, B = −0.04 [95% confidence interval: −0.080 to −0.002, P = 0.040)] and increased PWV by +103 cm/second (B = +4.1 [95% confidence interval: 0.6–7.6, P = 0.023]). CONCLUSIONS: This study shows that PR‐interval length, even in the conventionally normal range, is independently associated with endothelial dysfunction and increased arterial stiffness in healthy subjects free of atherosclerotic disease. This suggests the presence of a systemic, intermediate pathologic stage of the vasculature in PR prolongation before clinically manifest cardiovascular events, and could represent a mediating mechanism. © 2011 Wiley Periodicals, Inc. This study was supported by the CRCG Small Project Funding of the University of Hong Kong (Project No. 200907176063) and the Sun ChiehYeh Heart Foundation, Hong Kong, China. Yap‐Hang received a Best Paper Award at the Third Asian Preventive Cardiology and Cardiac Rehabilitation Conference, Hong Kong, China, December 11–12, 2010. The authors have no other funding, financial relationships, or conflicts of interest to disclose.