||Should heart rate variability be “corrected” for heart rate?
Biological, quantitative, and interpretive considerations
, , , and |
||Department of Biological
Psychology, Vrije Universiteit, Amsterdam,
||autonomic, behavioral medicine, heart rate, heart rate variability
||Metrics of heart period variability are widely used in the behavioral and biomedical
sciences, although somewhat confusingly labeled as heart rate variability (HRV).
Despite their wide use, HRV metrics are usually analyzed and interpreted without
reference to prevailing levels of cardiac chronotropic state (i.e., mean heart rate or
mean heart period). This isolated treatment of HRV metrics is nontrivial. All HRV
metrics routinely used in the literature exhibit a known and positive relationship with
the mean duration of the interval between two beats (heart period): as the heart period
increases, so does its variability. This raises the question of whether HRV metrics
should be “corrected” for the mean heart period (or its inverse, the heart rate). Here,
we outline biological, quantitative, and interpretive issues engendered by this question.
We provide arguments that HRV is neither uniformly nor simply a surrogate for
heart period. We also identify knowledge gaps that remain to be satisfactorily addressed
with respect to assumptions underlying existing HRV correction approaches.
In doing so, we aim to stimulate further progress toward the rigorous use and disciplined
interpretation of HRV. We close with provisional guidance on HRV reporting