Day‐to‐day blood pressure variability in COVID‐19: A biomarker of disrupted central autonomic network

Abstract

He and coworkers 1 provides several new insights into the significant relationships of day-to-day systolic blood pressure (SBP) variability, that is, standard derivation (SD), coefficient of variation (CV), and variability independent of mean (VIM)-with acute respiratory distress syndrome (ARDS) and mortality in 702 COVID-19 patients with hypertension. In addition, increased blood pressure (BP) variability was associated with severe inflammation and myocardial injury. 1 In COVID-19, systemic inflammation, 2 endothelial dysfunction, 3 breakdown of blood-brain-barrier (BBB), 4 and endocardial endothelial barrier, respectively, and alterations in cardiac response 5 have been considered to play pivotal roles in the pathophysiology of BP dysregulation leading to increased BP variability that could precede ARDS and critically ill in COVID-19 patients with hypertension. 1 In COVID-19, an excessive inflammation phase, so called a "cytokine storm", leads to end tissue damage and organ failure. 6 A fatal cytokine storm involves the release of considerable amounts of proinflammatory cytokines including IL-6 and TNF-α. 6 Under the influence of these proinflammatory cytokines, BBB integrity is locally impaired, enabling the influx of potentially neurotoxic endo-and xenobiotics into the brain parenchyma. This ultimately, via dysregulation of the central autonomic network (CAN) comprising the insular cortex (Ic), cingulate cortex, amygdala, hypothalamus, periaqueductal gray, parabrachial nucleus, nucleus of the tractus solitarius, and rostral ventrolateral medulla can lead to pathological activation of the sympathetic nervous system (SNS) predominance (Figure 1). 2,7,8 The carotid bodies, the principal peripheral chemoreceptors, are suggested to be a site of SARS-CoV-2 invasion because they are the site of the local expression of the receptor of angiotensin-converting enzyme. 9 On the other hand, COVID-19 enters through nasal infectionThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Perspectives of (/memorandum for) systems thinking on COVID‐19 pandemic and pathology

“…It is, however, well understood that elevated sympathetic activity (and parasympathetic hypoactivity), hyperglycaemia and immune-dysregulation are markers of a poor outcome; and potential pathophysiological mechanisms underlying this relationship have been identified. [79][80][81][82][83][84] If confirmed by carefully-planned prospective studies, these insights may help to prevent an unfavourable outcome of the disease; and they may also explain the conundrum of bio-social disparities in the prognosis of COVID-19. [85][86][87] F I G U R E 2 Physiological macroscopic multi-compartment and multi-level model of the organismic response to respiratory virus infection, along with stages of the viral invasion process, with conditions and reactions associated with affected compartments (modified from Tretter et al).…”

“…The potential relationship between chronic distress or type 2 allostasis and the severity of COVID‐19 is still understudied, and methodological problems hamper scientific progress in this intersection. It is, however, well understood that elevated sympathetic activity (and parasympathetic hypoactivity), hyperglycaemia and immune‐dysregulation are markers of a poor outcome; and potential pathophysiological mechanisms underlying this relationship have been identified 79–84 . If confirmed by carefully‐planned prospective studies, these insights may help to prevent an unfavourable outcome of the disease; and they may also explain the conundrum of bio‐social disparities in the prognosis of COVID‐19 85–87 …”

Investigating Autonomic Nervous System Dysfunction among Patients with Post- Covid Condition and Prolonged Cardiovascular Symptoms

“…Nevertheless, an imbalance of the autonomic nervous system has been suggested to determine the severity of Covid-19 20,27 . What is more, the data from the study of He et al 28 provided an important contribution to this notion; since they are considered within the context of the precise pathophysiology underlying the relationship between Covid-19 infection and day-to-day BP variability 7 . In line with this understanding, Li et al 6 observed greater variability of systolic arterial pressure in critically ill patients, when compared with their severe and discharged counterparts.…”

Investigating autonomic nervous system dysfunction among patients with post-COVID condition and prolonged cardiovascular symptoms

“…Nevertheless, an autonomic nervous system imbalance has been suggested to determine the severity of COVID-19 (32,42). Moreover, the data from the study of He et al (43) provided an essential contribution to this notion; they are considered within the context of the precise pathophysiology underlying the relationship between COVID-19 infection and day-to-day BP variability (19). In line with this understanding, Li et al (17) observed more significant systolic arterial pressure variability in critically ill patients when compared with their severe and discharged counterparts.…”

“…Until now, few reports have assessed the relationship between day-to-day blood pressure variability and mortality in COVID-19 (4,16). In addition to strict blood pressure control, it might be important to minimize day-to-day blood pressure variability to reduce mortality in COVID-19 patients (19).…”