The interplay of Heart Rate Variability, Stress, and Bio-functional Aging

Purpose

Heart rate variability (HRV) is a sensitive, non-invasive biomarker of autonomic regulation and psychophysiological adaptability. Reduced HRV has been linked to chronic stress, aging, and menopause-related hormonal changes. This study examined associations between HRV, chronic stress, and bio-functional health metrics within the Bern Cohort Study.

Methods

In this monocenter, cross-sectional subgroup analysis of the Bern Cohort Study 2014, 77 adults (81.8% female; mean age 37.6 ± 14.3 years; mean BMI 22.6 ± 3.1 kg/m²) with available HRV, bio-functional status (BFS), and and Trier Inventory for Chronic Stress (TICS) data were included. For analyses involving bio-functional age (BFA), only subjects aged ≥35 years were eligible (N = 36; mean age 51.8 ± 6.3 years). HRV was assessed using time-, frequency, and non-linear parameters. Chronic stress was measured with the TICS, and BFA was determined by standardized, validated procedures. Correlation and subgroup analyses explored associations between HRV, stress domains, chronological age, and BFS subcomponents.

Results

Chronological age was strongly negatively associated with HRV metrics (e.g., RMSSD: r = –0.595, p < 0.001), while BFA showed no significant relationship. Specific stress dimensions, such as social overload and tension, were inversely correlated with vagal markers, suggesting domain-specific autonomic reactivity. Selected BFS subparameters—particularly tapping frequency and reaction time—were significantly associated with HRV metrics, highlighting its relevance for physical and psychomotor vitality. Nonlinear HRV metrics further indicated reduced complexity under chronic stress.

Conclusion

HRV correlates meaningfully with selected physical and psychomotor components of functional health, offering physiological insight into individual vitality. While HRV alone does not reflect the full complexity of bio-functional aging, it can enrich multidimensional assessments such as the BFS. These findings support the integration of HRV into comprehensive models for evaluating and promoting healthy aging in midlife women.