A thirteen year prospective cohort study published online December 30, 2025 in the Journal of Alzheimer's Disease found that heart rate variability, a measure derived from the spacing between heartbeats, was not associated with later cognitive performance or with brain imaging markers in 269 cognitively unimpaired Dutch adults, once the analysis accounted for how much calcium had built up in their coronary arteries. The finding complicates a research line this section has followed as a candidate low-cost signal of autonomic nervous system and brain coupling.
The study drew its participants from the Netherlands based Lifelines cohort and two of its sub-studies, Imalife and Memolife. Researchers measured heart rate variability (specifically, the root mean square of successive differences between heartbeats) at two points, 2007 to 2013 and 2014 to 2017, then tracked cognition, blood based Alzheimer's biomarkers, and brain scans in the same people from 2022 to 2023, roughly thirteen years after the first heart rate reading. Participants were split into two groups by coronary artery calcification score measured on cardiac CT: those with none, and those with a high score of 300 or above.
Across the full sample, the researchers reported no consistent link between heart rate variability and any cognitive, imaging, or blood biomarker outcome. One narrow exception emerged: among adults with high coronary calcification, higher heart rate variability measured thirteen years earlier was associated with a lower serum amyloid-beta 42/40 ratio at follow-up, a pattern typically linked to Alzheimer's pathology, even though higher heart rate variability is usually read as a marker of a healthier cardiovascular state. The authors called the direction of that association unexpected and said it warrants cautious interpretation rather than clinical use.
The result lands alongside a UK Biobank analysis this newspaper reported that linked weaker heart rate variability signals to a higher later diagnosis of Parkinson's disease, part of a broader push to test whether heart rhythm patterns can serve as an early, inexpensive window into neurodegenerative disease risk across conditions. Taken together, the two studies suggest that any signal in heart rate variability may depend heavily on which disease, which subgroup, and which confounding factors, such as coronary calcification, are accounted for, rather than functioning as a general purpose biomarker.