Vagus nerve stimulation for treatment of drug-resistant epilepsy: a systematic review and meta-analysis.

To analyze the efficacy and safety of high-frequency VNS versus control (low-frequency VNS or no VNS) in patients with DRE using data from randomized controlled trials (RCTs). An electronic literature search was conducted on PubMed, EMBASE, and Cochrane Controlled Register of Trials (CENTRAL); 12 RCTs reporting seizure frequency or treatment response in studies containing a high-frequency VNS treatment arm (conventional VNS or transcutaneous VNS [tVNS]) compared to control (low-frequency VNS or no VNS) were included. Seizure frequency, treatment response (number of patients with ≥ 50% reduction in seizure frequency), quality of life (QOL), and adverse effects were analyzed. Seizure frequency was reported in 9 studies (718 patients). Meta-analysis with random-effects models favored high-frequency VNS over control (standardized mean difference = 0.82, 95%-CI = 0.39-1.24, p < .001). This remained significant for subgroup analyses of low-frequency VNS as the control, VNS modality, and after removing studies with moderate-to-high risk of bias. Treatment response was reported in 8 studies (758 patients). Random-effects models favored high-frequency VNS over control (risk ratio = 1.57, 95%-CI = 1.19-2.07, p < .001). QOL outcomes were reported descriptively in 4 studies (363 patients), and adverse events were reported in 11 studies (875 patients). Major side effects and death were not observed to be more common in high-frequency VNS compared to control. High-frequency VNS results in reduced seizure frequency and improved treatment response compared to control (low-frequency VNS or no VNS) in patients with drug-resistant epilepsy. Greater consideration for VNS in patients with DRE may be warranted to decrease seizure frequency in the management of these patients.

Effect of perioperative seizures on mortality and recurrence in patients with brain metastases.

Objective: To identify the independent risk factors for 30-day perioperative seizures, as well as to evaluate the effect of perioperative seizures on overall mortality and tumor recurrence among patients who underwent surgical resection of brain metastases. Methods: Patients who underwent surgical resection of brain metastases at our institution between 2011 and 2019 were included. 30-day perioperative seizures were defined as the presence of any preoperative or postoperative seizures diagnosed by a neurosurgeon or neurologist within 30 days of metastases resection. Independent risk factors for 30-day perioperative seizures were evaluated using multivariate logistic regression models. Kaplan-Meier plots and Cox regression models were constructed to evaluate the effects of 30-day perioperative seizures on overall mortality and tumor recurrence. Subgroup analyses were conducted for 30-day preoperative and 30-day postoperative seizures. Results: A total of 158 patients were included in the analysis. The mean (SD) age was 59.3 (12.0) years, and 20 (12.7%) patients had 30-day perioperative seizures. The presence of 30-day preoperative seizures (OR=41.4; 95% CI=4.76, 924; p=0.002) was an independent risk factor for 30-day postoperative seizures. Multivariate Cox regression revealed that any 30-day perioperative seizure (HR=3.25; 95% CI=1.60, 6.62; p=0.001) was independently and significantly associated with overall mortality but not tumor recurrence (HR=1.95; 95% CI=0.78, 4.91; p=0.154). Conclusions: Among patients with resected brain metastases, the presence of any 30-day perioperative seizure was independently associated with overall mortality. This suggests that 30-day perioperative seizures may be a prognostic marker of poor outcome. Further research evaluating this association as well as the effect of perioperative antiepileptic drugs in patients with resected brain metastases may be warranted.

Acute Ischemic Stroke During the Convalescent Phase of Asymptomatic COVID-2019 Infection in Men.

Importance: Acute ischemic stroke (AIS) is a known neurological complication in patients with respiratory symptoms of COVID-19 infection. However, AIS has not been described as a late sequelae in patients without respiratory symptoms of COVID-19. Objective: To assess AIS experienced by adults 50 years or younger in the convalescent phase of asymptomatic COVID-19 infection. Design, Setting, and Participants: This case series prospectively identified consecutive male patients who received care for AIS from public health hospitals in Singapore between May 21, 2020, and October 14, 2020. All of these patients had laboratory-confirmed asymptomatic COVID-19 infection based on a positive SARS-CoV-2 serological (antibodies) test result. These patients were individuals from South Asian countries (India and Bangladesh) who were working in Singapore and living in dormitories. The total number of COVID-19 cases (54 485) in the worker dormitory population was the population at risk. Patients with ongoing respiratory symptoms or positive SARS-CoV-2 serological test results confirmed through reverse transcriptase-polymerase chain reaction nasopharyngeal swabs were excluded. Main Outcomes and Measures: Clinical course, imaging, and laboratory findings were retrieved from the electronic medical records of each participating hospital. The incidence rate of AIS in the case series was compared with that of a historical age-, sex-, and ethnicity-matched national cohort. Results: A total of 18 male patients, with a median (range) age of 41 (35-50) years and South Asian ethnicity, were included. The median (range) time from a positive serological test result to AIS was 54.5 (0-130) days. The median (range) National Institutes of Health Stroke Scale score was 5 (1-25). Ten patients (56%) presented with a large vessel occlusion, of whom 6 patients underwent intravenous thrombolysis and/or endovascular therapy. Only 3 patients (17%) had a possible cardiac source of embolus. The estimated annual incidence rate of AIS was 82.6 cases per 100 000 people in this study compared with 38.2 cases per 100 000 people in the historical age-, sex-, and ethnicity-matched cohort (rate ratio, 2.16; 95% CI, 1.36-3.48; P < .001). Conclusions and Relevance: This case series suggests that the risk for AIS is higher in adults 50 years or younger during the convalescent period of a COVID-19 infection without respiratory symptoms. Acute ischemic stroke could be part of the next wave of complications of COVID-19, and stroke units should be on alert and use serological testing, especially in younger patients or in the absence of traditional risk factors.