Advisory Committee Chair
David E Vance
Advisory Committee Members
John J Shacka
Mirjam Colette-Kempf
Linda D Moneyham
Pariya L Fazeli-Wheeler
Olivio Clay
Document Type
Dissertation
Date of Award
2019
Degree Name by School
Doctor of Philosophy (PhD) School of Nursing
Abstract
Regardless of sufficient viral suppression, HIV exerts an ongoing inflammatory process that promotes chronic autonomic nervous system (ANS) dysfunction, accelerates physiological aging, and increases the risk of developing a spectrum of cognitive disorders (known as HIV-associated neurocognitive disorders [HAND]). Given this, identifying pathological mediators of this inflammatory response could provide insight into the mechanisms driving HAND. The vagus nerve (indexed by vagal-mediated heart rate variability [vmHRV]) could provide such a mediator as it regulates ANS activity via reciprocal cardio-neural pathways, which regulate inflammation and homeostasis. Vagal dysfunction is associated with persistent inflammatory signaling (e.g., stress or inflammatory-based disorders [such as HIV]), emotional dysregulation, and cognitive impairments. Chronically reduced vmHRV indices are observed in HIV-seropositive (SP) persons; however, cognitive studies examining vagal-HIV associations are lacking. In this dissertation, three articles were presented which focused on the vagal-HIV relationship to cognitive impairments. Article 1, a review of literature published in the journal of Neuropsychiatric Disease and Treatment, focused on vagal-mediated inflammatory processes relative to shared cognitive-behavioral symptomology (i.e., “sickness behavior”) in HIV infection and depression alike. This article identified vagal-HIV associations by utilizing a firmly established inflammatory-based disorder that primarily affects cognitive function (i.e., depression). It concluded with an appeal to conduct cognitive research in HIV utilizing vagal-mediated measures, which leads to Article 2. Article 2, submitted to the Journal of Affective Disorders, examined the concept of self-regulation in HAND. This article operationalizes self-regulation (emotional and cognitive domains) as an interrelated, adaptive, vagal-mediated process (i.e., cardio-neural continuum between cortical and sub-cortical systems) influenced by inflammatory activity. While unexplored in HIV literature, self-regulatory function (indexed by vmHRV) provides an indicator of cognitive impairment that is sensitive to emotional stressors (e.g., early mal-adaptive experiences) that are known to predispose HIV-SP persons (particularly women) to worse outcomes. Therefore, using vmHRV as a measure of ANS activity, Article 3 examined HIV’s effect on cognitive function in HIV-SP women. Article 3 was the primary research study for this dissertation, which integrates assumed inflammatory effects of HIV and compounding stressors on vagal-mediated measures relative to cognitive function. From this, earlier detection and interventions for cognitive impairments could result.
Recommended Citation
Nicholson, William C., "Vagal Mediated Heart Rate Variability And Cognitive Impairments In Hiv-Seropositive Women" (2019). All ETDs from UAB. 2589.
https://digitalcommons.library.uab.edu/etd-collection/2589
