In a groundbreaking study that merges cardiovascular research with cognitive neuroscience, scientists have uncovered compelling evidence linking long-term fluctuations in resting heart rate variability (RHRV) to cognitive decline. Published in BMC Psychiatry in 2025, this research draws from two extensive, nationally representative cohorts—the Health and Retirement Study (HRS) from the United States and the China Health and Retirement Longitudinal Study (CHARLS). By analyzing visit-to-visit variations in heart rate over prolonged periods, the researchers reveal novel insights into how subtle physiological changes in heart rhythm may predict deteriorations in cognitive functions such as memory, attention, and orientation.
Resting heart rate variability refers to the natural variations in the time intervals between heartbeats, reflecting the dynamic interplay of the autonomic nervous system’s sympathetic and parasympathetic branches. Traditionally, RHRV has been associated with cardiovascular health, with reduced variability often signaling increased risk for heart disease. However, the present study extends this concept to neurocognitive domains, proposing that long-term visit-to-visit variability in resting heart rate carries significant implications for brain health and cognitive aging.
The research team utilized variation independent of mean (VIM) as the principal metric for assessing RHRV, a refined measure that accounts for average heart rate levels and focuses more precisely on the variability component. Pooling data from a combined total of 11,667 participants—7,582 from HRS and 4,085 from CHARLS—enabled the study to achieve a remarkable statistical power and cross-cultural relevance. Participants were required to have multiple resting heart rate measurements across different visits, ensuring the robustness of the visit-to-visit variability assessment.
Cognitive function was evaluated using a battery of neuropsychological tests standardized across both cohorts. These tests probed multiple domains, including memory retention, selective attention, and temporal-spatial orientation. To synthesize these scores, the researchers computed a standardized Z-score reflecting global cognitive ability. The longitudinal design allowed for tracking changes in cognitive function over time, critical for understanding the dynamics between RHRV and cognitive trajectories rather than static snapshots.
Using linear mixed models, which accommodate both fixed effects and individual variability over time, the researchers identified consistent, statistically significant negative associations between higher VIM of RHRV and cognitive performance. Specifically, each standard deviation increase in VIM corresponded to a decline in global cognitive functioning—β values of −0.022 in the HRS cohort and −0.023 in CHARLS—pointing to a robust, replicable relationship across diverse populations.
Further reinforcing their findings, the study implemented several sensitivity analyses. Alternative measures of RHRV, such as average real variability and coefficient of variation, yielded consistent results, indicating that the association is not circumscribed to a single metric but reflects a genuine physiological phenomenon. Moreover, adjustments for lifestyle factors such as physical activity, as well as health confounders including pre-existing cardiovascular conditions and systemic inflammation markers like C-reactive protein, did not substantially alter the observed relationships. This implies that RHRV’s link to cognitive decline operates independently of these common confounds.
These results add a crucial layer of understanding to the complex interrelationship between cardiovascular dynamics and neurodegeneration. Previous studies have often focused on episodic or short-term heart rate variability, but this investigation highlights the importance of long-term visit-to-visit fluctuations. Such variability may be indicative of underlying autonomic dysregulation or vascular instability, which in turn could affect cerebral blood flow and neural network function, gradually impairing cognition.
The implications are profound for early detection and prevention strategies aimed at cognitive decline and dementia. Monitoring long-term RHRV patterns could serve as a non-invasive biomarker, allowing healthcare providers to identify at-risk individuals well before overt symptoms of cognitive impairment emerge. This approach aligns with the growing field of precision medicine, leveraging longitudinal physiological data to tailor interventions and possibly slow down the progression of cognitive illnesses.
Furthermore, the study bridges a critical gap by incorporating data from two national cohorts with differing genetic backgrounds, environmental exposures, and healthcare systems. The consistency across the U.S.-based HRS and China’s CHARLS underscores the potential universality of RHRV’s predictive capacity, suggesting similar biological mechanisms may be at play globally, transcending cultural and ethnic differences.
While the study presents compelling epidemiological evidence, the authors call for further mechanistic investigations to unravel the precise biological pathways linking heart rate variability fluctuations to neural decline. Possible candidates include chronic stress responses mediated by the autonomic nervous system, endothelial dysfunction affecting cerebral microvasculature, or systemic inflammation that impairs neuroplasticity. Understanding these mechanistic underpinnings will be crucial for developing targeted therapeutics.
In summary, this pioneering research illuminates the promising frontier where cardiology intersects with cognitive aging. By leveraging long-term visit-to-visit RHRV as a dynamic physiological marker, clinicians and scientists gain a novel tool for early identification of cognitive vulnerability. Coupled with traditional risk assessments, RHRV monitoring could revolutionize how we approach brain health maintenance in aging populations, offering hope for mitigating the burdens of dementia and cognitive impairment worldwide.
Given the rapidly aging global population and the escalating public health challenge posed by cognitive disorders, such integrative biomarker approaches are both timely and essential. This study not only expands the landscape of cardiovascular biomarkers but also heralds a new paradigm in understanding and managing cognitive decline through longitudinal physiological data.
As the field advances, integrating wearable technologies and continuous monitoring devices capable of capturing heart rate variability outside clinical settings will enhance the feasibility and scalability of RHRV-based cognitive risk assessments. Such innovations promise to democratize access to precision cognitive diagnostics, enabling proactive brain health interventions at the population level.
Finally, the confluence of cardiovascular and cognitive research embodied in this study sets the stage for interdisciplinary collaborations. Neuroscientists, cardiologists, epidemiologists, and data scientists stand to benefit from these findings, synergizing their expertise to decode the complex biological narratives connecting heart rhythms and mind function over the human lifespan.
Subject of Research: The association between long-term visit-to-visit resting heart rate variability (RHRV) and cognitive decline in aging populations.
Article Title: Association between long-term visit-to-visit resting heart rate variability and cognitive decline: evidence from two national cohorts.
Article References:
Zheng, G., Zhou, B., Fang, Z. et al. Association between long-term visit-to-visit resting heart rate variability and cognitive decline: evidence from two national cohorts. BMC Psychiatry 25, 751 (2025). https://doi.org/10.1186/s12888-025-07208-1
Image Credits: AI Generated
