Case Report of Improvement in Long-COVID Symptoms in an Air Force Medic Treated With Transcranial Magnetic Stimulation Using Electro-Magnetic Brain Pulse Technique

Non-invasive Brain Stimulation for Post-COVID-19 Conditions: A Systematic Review

BACKGROUND

Alongside the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, the number of patients with persistent symptoms following acute infection with SARS-CoV-2 is of concern. It is estimated that at least 65 million people worldwide meet criteria for what the World Health Organization (WHO) defines as "post-COVID-19 condition" - a multisystem disease comprising a wide range of symptoms. Effective treatments are lacking. In the present review, we aim to summarize the current evidence for the effectiveness of non-invasive or minimally invasive brain stimulation techniques in reducing symptoms of post-COVID-19.

METHODS

After pre-registration with PROSPERO, the review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA). The four electronic databases PubMed/MEDLINE, PsycINFO, Web of Science and Scopus were systematically searched for all relevant studies through April 2nd, 2024. Two independent investigators selected empirical papers that reported on the application of non- or minimally invasive brain stimulation in patients with post-COVID-19 conditions.

RESULTS

A total of 19 studies were identified, one using transcutaneous vagus nerve stimulation (tVNS), another using transorbital alternating current stimulation (toACS), 6 studies on transcranial magnetic stimulation (TMS) and 11 studies on transcranial direct current stimulation (tDCS) for the treatment of post-COVID-19 symptoms.

CONCLUSIONS

Existing studies report first promising results, illustrating improvement in clinical outcome parameters. Yet, the mechanistic understanding of post-COVID-19 and how brain stimulation techniques may be benefitial are limited. Directions for future research in the field are discussed.

Post-COVID-19 Condition in Military Personnel

INTRODUCTION

During the COVID-19 pandemic, a significant number of individuals experienced persistent symptoms, collectively termed post-COVID-19 condition (PCC) by the World Health Organization. While civilian prevalence has been extensively studied, little is known about PCC in military personnel. This article highlights the need for increased awareness, documentation, and research on PCC within the military context, utilizing the Defense Health Agency database.

MATERIALS AND METHODS

A keyword search of the PubMed, CINAHL, and Web of Science databases was performed utilizing the keywords: military, post-COVID conditions, long COVID-19, and post-COVID19 syndrome. A five-stage integrative review framework was used to analyze 40 reports and research articles published from 2019 to 2023 to assess the current state of PCC research, including epidemiology, severe acute respiratory syndrome coronavirus 2 variants, pathophysiology, and prevalence in military personnel.

RESULTS

Our review revealed a notable gap in research on PCC within the military population, with only a few mentions in the literature. A key finding was the association between immunization status, symptom severity, and ethnicity in PCC development.

CONCLUSION

To comprehensively address PCC in military personnel, it is imperative to foster both awareness and documentation. Creating a centralized Defense Health Agency-DoD repository for active duty service members with PCC diagnoses offers a valuable opportunity to conduct trend analysis, identify missed cases, and better understand the individual and military readiness implications of this condition. Additionally, to address the educational needs of clinicians, it is essential to develop continuing medical education and continuing nursing education programs focusing on PCC signs, symptoms, and their impact on readiness. Furthermore, randomized controlled trials and longitudinal experimental clinical trials are essential for monitoring service members over time, providing valuable insights into the course of PCC and potential interventions. These research endeavors collectively contribute to improving the health, readiness, and care of military personnel affected by PCC.

Decoding Post-Viral Fatigue: The Basal Ganglia's Complex Role in Long-COVID

Long-COVID afflicts millions with relentless fatigue, disrupting daily life. The objective of this narrative review is to synthesize current evidence on the role of the basal ganglia in long-COVID fatigue, discuss potential mechanisms, and highlight promising therapeutic interventions. A comprehensive literature search was conducted using PubMed, Scopus, and Web of Science databases. Mounting evidence from PET, MRI, and functional connectivity data reveals basal ganglia disturbances in long-COVID exhaustion, including inflammation, metabolic disruption, volume changes, and network alterations focused on striatal dopamine circuitry regulating motivation. Theories suggest inflammation-induced signaling disturbances could impede effort/reward valuation, disrupt cortical-subcortical motivational pathways, or diminish excitatory input to arousal centers, attenuating drive initiation. Recent therapeutic pilots targeting basal ganglia abnormalities show provisional efficacy. However, heterogeneous outcomes, inconsistent metrics, and perceived versus objective fatigue discrepancies temper insights. Despite the growing research, gaps remain in understanding the precise pathways linking basal ganglia dysfunction to fatigue and validating treatment efficacy. Further research is needed to advance understanding of the basal ganglia's contribution to long-COVID neurological sequelae and offer hope for improving function across the expanding affected population.

Neurovascular coupling impairment as a mechanism for cognitive deficits in COVID-19

Components that comprise our brain parenchymal and cerebrovascular structures provide a homeostatic environment for proper neuronal function to ensure normal cognition. Cerebral insults (e.g. ischaemia, microbleeds and infection) alter cellular structures and physiologic processes within the neurovascular unit and contribute to cognitive dysfunction. COVID-19 has posed significant complications during acute and convalescent stages in multiple organ systems, including the brain. Cognitive impairment is a prevalent complication in COVID-19 patients, irrespective of severity of acute SARS-CoV-2 infection. Moreover, overwhelming evidence from in vitro, preclinical and clinical studies has reported SARS-CoV-2-induced pathologies in components of the neurovascular unit that are associated with cognitive impairment. Neurovascular unit disruption alters the neurovascular coupling response, a critical mechanism that regulates cerebromicrovascular blood flow to meet the energetic demands of locally active neurons. Normal cognitive processing is achieved through the neurovascular coupling response and involves the coordinated action of brain parenchymal cells (i.e. neurons and glia) and cerebrovascular cell types (i.e. endothelia, smooth muscle cells and pericytes). However, current work on COVID-19-induced cognitive impairment has yet to investigate disruption of neurovascular coupling as a causal factor. Hence, in this review, we aim to describe SARS-CoV-2's effects on the neurovascular unit and how they can impact neurovascular coupling and contribute to cognitive decline in acute and convalescent stages of the disease. Additionally, we explore potential therapeutic interventions to mitigate COVID-19-induced cognitive impairment. Given the great impact of cognitive impairment associated with COVID-19 on both individuals and public health, the necessity for a coordinated effort from fundamental scientific research to clinical application becomes imperative. This integrated endeavour is crucial for mitigating the cognitive deficits induced by COVID-19 and its subsequent burden in this especially vulnerable population.