Chronic vagus nerve stimulation for drug-resistant epilepsy may influence fasting blood glucose concentration

Navigating the waves: A systematic review of telemedicine interventions and health service access challenges in epilepsy during COVID-19

INTRODUCTION

The COVID-19 pandemic has dramatically reshaped the landscape of healthcare delivery, prompting a surge in the adoption of telemedicine as a means to ensure continuity of care. During the pandemic, patients with epilepsy experienced difficulties accessing healthcare and obtaining necessary medications, with a substantial percentage facing obstacles in acquiring anti-seizure medication and reaching healthcare professionals. Disruptions in the supply and distribution of medication, due to COVID-19-related actions, further caused more problems for people with epilepsy and their caregivers like increasing seizure frequency. The pandemic has also accelerated the adoption of telemedicine, with evidence suggesting its potential benefits in various medical fields. In this systematic review and meta-analysis, we aim to investigate the challenges faced by patients with epilepsy during the COVID-19 pandemic, including healthcare access and medication acquisition, as well as evaluate changes in seizure frequency. Additionally, we will synthesize existing evidence on the use of telemedicine to address the healthcare needs of these patients, exploring its advantages and limitations.

METHODS

This systematic review was prepared using PRISMA reporting guidelines. The databases searched were PubMed, Scopus, Web of Science, and Cochrane. Risk of Bias was assessed using Joanna Briggs Institute (JBI). Following rigorous application of eligibility criteria, relevant data, covering both telemedicine-related and health service access information, were methodically extracted and organized using Microsoft Excel spreadsheets. The analytical procedures were executed through the utilization of Comprehensive Meta-Analysis (CMA) software.

RESULTS

A total of 70 articles included in this review. Regarding difficulties in accessing healthcare, 34% of PWE and 41% of caregivers experienced cancelled, changed or postponed appointments. Following issues with obtaining medicine, 13% of patients and 16% of caregivers had difficulties in medicine availability and 11% of patients and 10% of caregivers in medicine accessibility. A very high rate of 90% satisfaction with telemedicine was reported by PWE. 17.6% of PWE experienced an escalation, 9% a decrease and 67% no changes in seizure frequency.

CONCLUSION

This review and meta-analysis revealed that telemedicine and virtual communications have been helpful but not sufficient for meeting healthcare needs for PWE during the COVID-19 pandemic. Additionally, there was a significant increase in seizure frequency among PWE who had difficulty obtaining medicine and access to healthcare.

The Vagus Nerve Regulates Immunometabolic Homeostasis in the Ovine Fetus near Term: The Impact on Terminal Ileum

BACKGROUND

Glucosensing elements are widely distributed throughout the body and relay information about circulating glucose levels to the brain via the vagus nerve. However, while anatomical wiring has been established, little is known about the physiological role of the vagus nerve in glucosensing. The contribution of the vagus nerve to inflammation in the fetus is poorly understood. Increased glucose levels and inflammation act synergistically when causing organ injury, but their interplay remains incompletely understood. We hypothesized that vagotomy (Vx) will trigger a rise in systemic glucose levels and this will be enhanced during systemic and organ-specific inflammation. Efferent vagus nerve stimulation (VNS) should reverse this phenotype.

METHODS

Near-term fetal sheep (n = 57) were surgically prepared using vascular catheters and ECG electrodes as the control and treatment groups (lipopolysaccharide (LPS), Vx + LPS, Vx + LPS + selective efferent VNS). The experiment was started 72 h postoperatively to allow for post-surgical recovery. Inflammation was induced with LPS bolus intravenously (LPS group, 400 ng/fetus/day for 2 days; n = 23). For the Vx + LPS group (n = 11), a bilateral cervical vagotomy was performed during surgery; of these n = 5 received double the LPS dose, LPS800. The Vx + LPS + efferent VNS group (n = 8) received cervical VNS probes bilaterally distal from Vx in eight animals. Efferent VNS was administered for 20 min on days 1 and 2 +/10 min around the LPS bolus. Fetal arterial blood samples were drawn on each postoperative day of recovery (-72 h, -48 h, and -24 h) as well as at the baseline and seven selected time points (3-54 h) to profile inflammation (ELISA IL-6, pg/mL), insulin (ELISA), blood gas, and metabolism (glucose). At 54 h post-LPS, a necropsy was performed, and the terminal ileum macrophages' CD11c (M1 phenotype) immunofluorescence was quantified to detect inflammation. The results are reported for p < 0.05 and for Spearman R2 > 0.1. The results are presented as the median (IQR).

RESULTS

Across the treatment groups, blood gas and cardiovascular changes indicated mild septicemia. At 3 h in the LPS group, IL-6 peaked. That peak was decreased in the Vx + LPS400 group and doubled in the Vx + LPS800 group. The efferent VNS sped up the reduction in the inflammatory response profile over 54 h. The M1 macrophage activity was increased in the LPS and Vx + LPS800 groups only. The glucose and insulin concentrations in the Vx + LPS group were, respectively, 1.3-fold (throughout the experiment) and 2.3-fold higher vs. control (at 3 h). The efferent VNS normalized the glucose concentrations.

CONCLUSIONS

The complete withdrawal of vagal innervation resulted in a 72-h delayed onset of a sustained increase in glucose for at least 54 h and intermittent hyperinsulinemia. Under the conditions of moderate fetal inflammation, this was related to higher levels of gut inflammation. The efferent VNS reduced the systemic inflammatory response as well as restored both the concentrations of glucose and the degree of terminal ileum inflammation, but not the insulin concentrations. Supporting our hypothesis, these findings revealed a novel regulatory, hormetic, role of the vagus nerve in the immunometabolic response to endotoxin in near-term fetuses.

[Research advances in neuromodulation techniques for blood glucose regulation and diabetes intervention]

Diabetes and its complications that seriously threaten the health and life of human, has become a public health problem of global concern. Glycemic control remains a major focus in the treatment and management of patients with diabetes. The traditional lifestyle interventions, drug therapies, and surgeries have benefited many patients with diabetes. However, due to problems such as poor patient compliance, drug side effects, and limited surgical indications, there are still patients who fail to effectively control their blood glucose levels. With the development of bioelectronic medicine, neuromodulation techniques have shown great potential in the field of glycemic control and diabetes intervention with its unique advantages. This paper mainly reviewed the research advances and latest achievements of neuromodulation technologies such as peripheral nerve electrical stimulation, ultrasound neuromodulation, and optogenetics in blood glucose regulation and diabetes intervention, analyzed the existing problems and presented prospects for the future development trend to promote clinical research and application of neuromodulation technologies in the treatment of diabetes.

Transcutaneous auricular vagus nerve stimulation augments postprandial inhibition of ghrelin

Vagus nerve stimulation (VNS) facilitates weight loss in animals and patients treated with VNS for depression or epilepsy. Likewise, chronic transcutaneous auricular VNS (taVNS) reduces weight gain and improves glucose tolerance in Zucker diabetic fatty rats. If these metabolic effects of taVNS observed in rats translate to humans is unknown. Therefore, the hypothesis of this study was that acute application of taVNS affects glucotropic and orexigenic hormones which could potentially facilitate weight loss and improve glucose tolerance if taVNS were applied chronically. In two single-blinded randomized cross-over protocols, blood glucose levels, plasma concentrations of insulin, C-peptide, glucagon, leptin, and ghrelin, together with heart rate variability and baroreceptor-heart rate reflex sensitivity were determined before and after taVNS (left ear, 10 Hz, 300 µs, 2.0-2.5 mA, 30 min) or sham-taVNS (electrode attached to ear with the stimulator turned off). In a first protocol, subjects (n = 16) were fasted throughout the protocol and in a second protocol, subjects (n = 10) received a high-calorie beverage (220 kCal) after the first blood sample, just before initiation of taVNS or sham-taVNS. No significant effects of taVNS on heart rate variability and baroreceptor-heart rate reflex sensitivity and only minor effects on glucotropic hormones were observed. However, in the second protocol taVNS significantly lowered postprandial plasma ghrelin levels (taVNS: -115.5 ± 28.3 pg/ml vs. sham-taVNS: -51.2 ± 30.6 pg/ml, p < 0.05). This finding provides a rationale for follow-up studies testing the hypothesis that chronic application of taVNS may reduce food intake through inhibition of ghrelin and, therefore, may indirectly improve glucose tolerance through weight loss.

The effects of coronavirus disease 2019 (COVID-19) pandemic on people with epilepsy (PwE): an online survey-based study

During the unprecedented COVID-19 pandemic in 2020, the whole world faced an unusual health emergency. Medical care of chronic neurological diseases, such as Epilepsy, is being neglected. In this survey, we aimed to evaluate the impact of the COVID-19 pandemic on the care of people with Epilepsy (PwE) and to identify their risk factors for seizure worsening to direct better future medical care. We administered a web-based survey (submitted on August 5, 2020). It included socio-demographic, Epilepsy-related, and psychometric data (The Depression, Anxiety, and Stress Scale—21 Items(DASS21) and The Pittsburgh Sleep Quality Index (PSQI). Regression analysis identified predictors of seizure worsening. We collected responses from an online survey of PwE during the pandemic. Out of 151 responders, 71 patients complained of issues related to Epilepsy management and all of whom reached the treating physician and solved their problems. Sleep quality was compromised in 84 patients (55.6%). Two-thirds of the patients in our cohort (66.2%) reported depression, 72.2% reported anxiety, and 75.5% reported stress. Eight patients (5.3%) got COVID-19 infection, and only one patient suffered from mild worsening of the seizure. The main concerns were shortage of medications for 46 (30.5%) patients, getting Coronavirus infection for 67 (44.4%) patients, and seizure worsening for 32 (21.3%) patients. Thirty-five patients (23.2%) reported seizure worsening, which was best explained by retirement or jobless state, having moderate or severe stress, poor sleep quality, vagus nerve stimulation (VNS), fear of getting COVID-19 infection, fear of worsening of seizures, or shortage of medication. During the current COVID-19 pandemic, a significant percentage of PwE experienced worsening of their seizures. This unusual, challenging experience clarifies the urgent need to establish telemedicine services and home-based management of Epilepsy, including ambulatory EEG, home video, and medication delivery to patients’ homes to provide continuous medical care.