Cerebral venous thrombosis (CVT), a rare thrombotic event that can cause serious neurologic deficits, has been reported after some ChAdOx1 nCoV-19 vaccinations against coronavirus disease 2019 (COVID-19). However, there are few reports of associations between COVID-19 mRNA vaccination and CVT. We retrospectively analyzed CVT occurrence, time of onset after vaccination, outcomes (recovered/not recovered), and death after COVID-19 vaccination from adverse drug reactions (ADR) reports in VigiBase. A disproportionality analysis was performed regarding COVID-19 mRNA vaccines (BNT162b2 and mRNA-1273) and the ChAdOx1 nCoV-19 vaccine. We identified 756 (0.07%) CVT cases (620 (0.05%) after BNT162b2 and 136 (0.01%) after mRNA-1273) of 1,154,023 mRNA vaccine-related ADRs. Significant positive safety signals were noted for COVID-19 mRNA vaccines (95% lower end of information component = 1.56; reporting odds ratio with 95% confidence interval (CI) = 3.27). The median days to CVT onset differed significantly between the BNT162b2 and ChAdOx1 nCoV-19 vaccines (12 (interquartile range, 3–22) and 11 (interquartile range, 7–16), respectively; p = 0.02). Fewer CVT patients died after receiving mRNA vaccines than after receiving the ChAdOx1 nCoV-19 vaccine (odds ratio, 0.32; 95% CI, 0.22–0.45; p < 0.001). We noted a potential safety signal for CVT occurrence after COVID-19 mRNA vaccination. Therefore, awareness about the risk of CVT, even after COVID-19 mRNA vaccination, is necessary.

Park H, et al. J Clin Neurol. 2025 Nov;21(6):514-526. https://doi.org/10.3988/jcn.2025.0317

Background: There is inadequate information on the validation of diabetic microvascular complications in the Korean National Health Insurance Service data set. We aimed to validate the diagnostic algorithms regarding the nephropathy, neuropathy, and retinopathy of diabetes.Methods: From various secondary and tertiary medical centers, we selected 6,493 patients aged ≥ 40 years who were diagnosed with diabetic microvascular complications more than once based on codes in the 10th version of the International Classification of Diseases (ICD-10). During 2019 and 2020, we randomly selected the diagnoses of 200 patients, 100 from each of two hospitals. The positive predictive value (PPV), negative predictive value, error rate, sensitivity, and specificity were determined for each diabetic microvascular complication according to the ICD-10 codes, laboratory findings, diagnostic studies, and treatment procedure codes.Results: Among the 200 patients who visited the hospital more than once and had the diagnostic codes of diabetic microvascular complications, 142, 110, and 154 patients were confirmed to have the gold standard of diabetic nephropathy (PPV, 71.0%), diabetic neuropathy (PPV, 55.0%), and diabetic retinopathy (PPV, 77.0%), respectively. The PPV and specificity of diabetic nephropathy (PPV, 71.0–81.4%; specificity, 10.3–53.4%), diabetic neuropathy (PPV, 55.0–81.3%; specificity, 66.7–76.7%) and diabetic retinopathy (PPV, 77.0–96.6%; specificity, 2.2–89.1%) increased after combining them with the laboratory findings, diagnostic studies, and treatment procedures codes. These change trends were observed similarly for both hospitals.Conclusions: Defining diabetic microvascular complications using ICD-10 codes and their related examination codes may be a feasible method for studying diabetic complications.

Background: The CHADS₂, CHA₂DS₂-VASc, ATRIA, and Essen scores have been developed for predicting vascular outcomes in stroke patients. We investigated the association between these stroke risk scores and unsuccessful recanalization after endovascular thrombectomy (EVT). Methods: From the nationwide multicenter registry (Selection Criteria in Endovascular Thrombectomy and Thrombolytic therapy (SECRET)) (Clinicaltrials.gov NCT02964052), we consecutively included 501 patients who underwent EVT. We identified pre-admission stroke risk scores in each included patient. Results: Among 501 patients who underwent EVT, 410 (81.8%) patients achieved successful recanalization (mTICI ≥ 2b). Adjusting for body mass index and p < 0.1 in univariable analysis revealed the association between all stroke risk scores and unsuccessful recanalization (CHADS₂ score: odds ratio (OR) 1.551, 95% confidence interval (CI) 1.198–2.009, p = 0.001; CHA₂DS₂VASc score: OR 1.269, 95% CI 1.080–1.492, p = 0.004; ATRIA score: OR 1.089, 95% CI 1.011–1.174, p = 0.024; and Essen score: OR 1.469, 95% CI 1.167–1.849, p = 0.001). The CHADS₂ score had the highest AUC value and differed significantly only from the Essen score (AUC of CHADS₂ score; 0.618, 95% CI 0.554–0.681). Conclusion: All stroke risk scores were associated with unsuccessful recanalization after EVT. Our study suggests that these stroke risk scores could be used to predict recanalization in stroke patients undergoing EVT.

Background and Objectives: Although reversible cerebral vasoconstriction syndrome (RCVS) is a rare disease, the condition may occur with COVID-19 infection. We aimed to investigate the clinical characteristics of RCVS through a systematic review of case reports and case series that reported on COVID-19-related RCVS. Methods: A literature search was performed in PubMed (MEDLINE), SCOPUS, and Web of Science. The search was confined to articles published between 17 November 2019 and 14 August 2024. The search terms were (“COVID-19” OR “SARS CoV-2”) AND (“RCVS” OR “Reversible cerebral vasoconstriction syndrome”). The search protocol was registered in PROSPERO (CRD42024491818). A total of twenty-four cases were included, nine case series consisting of nineteen cases and five cases from our hospital. Clinical characteristics were investigated, including risk factors, symptoms, brain and angiographic findings, treatment options, and prognoses. Results: The average age was 37.1 years, and females comprised 70.8% of the cohort. COVID-19 vaccination was administered in five cases. Vasoconstriction was most frequently noted in middle cerebral arteries (90.9%). Among the included patients, 12 (50.0%) experienced strokes as a complication of RCVS, and the mortality rate was 9.1%. Follow-up imaging findings were available for 14 of the 24 cases (58.3%). Among these, vasoconstriction was fully improved in 64.3%, partially improved in 28.6%, and aggravated in 7.1%. Conclusions: While the recovery rate of vasoconstriction on brain angiographic findings was not uncommon, our systematic review indicates a potential for a relatively poor neurological prognosis in COVID-19-related RCVS.

While varicose vein (VV) and dementia are frequent health problems, research investigating association between these conditions has been limited. We aimed to investigate the relationship between the presence of VV and the development of dementia, as well as to evaluate whether treatment for VV correlates with the occurrence of dementia in a longitudinal study involving the general population. Our study included 430,875 participants based on health screening results conducted from 2005 to 2010 in the South Korean health screening cohort database. Presence of VV was defined with at least two or more claims based on International Classification of Diseases, Tenth Revision (ICD-10) of I830-832, I839, or I868. Propensity score matching at a ratio of 1:5 was employed to categorize the participants into two groups based on the presence and treatment of VV, respectively. Primary outcome was the incidence of all-cause dementia with two or more claims based on ICD-10 code (F00-03, G30, and G31), and secondary outcomes considered occurrence of Alzheimer’s disease (AD; F00 or G30) and vascular dementia (VD; F01). Among included participants, presence of VV were noted in 5,096 (1.3%) participants. During a median follow-up of 13.33 (interquartile range 10.4–16.26) years, 55,329 (13.9%) cases of all-cause dementia have occurred. In multivariable analysis, VV group showed increased risk of all-cause dementia compared to non-VV group (hazard ratio [HR]: 1.235, 95% confidence interval [CI]: 1.147–1.329). Contrary to AD, treatment of VV group was significantly associated with decreased risk of VD (HR: 0.566, 95% CI: 0.382–0.841). Our study showed that presence of VV may be associated with an increased risk of future all-cause dementia, and treatment of VV was likely to reduce the incidence risk of VD.