Jungwon Min, Jeremy Rouanet, Alessandra Cadete Martini, Kaoru Nashiro, Hyun Joo Yoo, Shai Porat, Christine Cho, Junxiang Wan, Steve W. Cole, Elizabeth Head, Daniel A. Nation, Julian F. Thayer & Mara Mather
Slow paced breathing via heart rate variability (HRV) biofeedback stimulates vagus-nerve pathways that counter noradrenergic stress and arousal pathways that can influence production and clearance of Alzheimer’s disease (AD)-related proteins. Thus, we examined whether HRV biofeedback intervention affects plasma Αβ40, Αβ42, total tau (tTau), and phosphorylated tau-181 (pTau-181) levels. We randomized healthy adults (N = 108) to use slow-paced breathing with HRV biofeedback to increase heart rate oscillations (Osc+) or to use personalized strategies with HRV biofeedback to decrease heart rate oscillations (Osc−). They practiced 20–40 min daily. Four weeks of practicing the Osc+ and Osc− conditions produced large effect size differences in change in plasma Aβ40 and Aβ42 levels. The Osc+ condition decreased plasma Αβ while the Osc− condition increased Αβ. Decreases in Αβ were associated with decreases in gene transcription indicators of β-adrenergic signaling, linking effects to the noradrenergic system. There were also opposing effects of the Osc+ and Osc− interventions on tTau for younger adults and pTau-181 for older adults. These results provide novel data supporting a causal role of autonomic activity in modulating plasma AD-related biomarkers.