Study of cognitive functions and heart rate variability in reproductive-age group and post-menopausal women

Background The menopausal transition is associated with hormonal, cognitive, and autonomic changes, yet the interplay between cognitive function and autonomic regulation-measured via heart rate variability (HRV) remains underexplored in Indian women.

Aims The study aimed to compare cognitive performance and HRV parameters between reproductive-age and post-menopausal women, and to assess the relationship between cognitive domains and HRV indices.

Methods A cross-sectional study was conducted at a tertiary care center of Northern India, enrolling 240 healthy women (120 reproductive-age, 20-40 years; 120 post-menopausal, 45-60 years). Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA), while HRV was evaluated via 5-min resting ECG. Time-domain [standard deviation of NN interval (SDNN), root mean square of successive differences (RMSSD), proportion of NN50 (pNN50), mean RR] and frequency-domain [low-frequency (LF) and high-frequency (HF), LF/HF ratio] HRV metrics were analyzed.

Results Post-menopausal women showed significantly lower MoCA scores than reproductive-age women (22.35 ± 3.17 vs. 25.54 ± 2.34, P < 0.001), with pronounced deficits in executive function, memory, and abstraction. Interestingly, the language domain score was significantly higher in the post-menopausal group. HRV analysis revealed significantly longer RR intervals and higher parasympathetic indices (RMSSD, pNN50, HF power) in post-menopausal women, while LF-power was lower; however, LF/HF ratio remained unchanged between groups (P = 0.96). Positive correlations were observed between MoCA scores and SDNN, mean RR; LF/HF ratio correlated negatively with cognitive scores in both groups.

Conclusion Post-menopausal women exhibited cognitive deficits-particularly in executive and memory domains-alongside distinct alterations in autonomic function. Contrary to expectations, HRV parameters indicated preserved or enhanced parasympathetic modulation in the older group. These findings underscore the relevance of autonomic-cognitive coupling in aging women and support HRV can be a potential biomarker of cognitive health.