Heart rate variability analysis using electrocardiograms during cardio-ankle vascular index measurement shows good agreement with resting electrocardiogram-based analysis in patients with diabetes: a retrospective cross-sectional study

Background Cardiovascular autonomic neuropathy (CAN) is a common but underrecognized diabetic complication. Although heart rate variability (HRV) analysis is a less invasive alternative to cardiovascular autonomic reflex tests, it is not routinely performed due to time and equipment constraints. This study aimed to assess whether HRV analysis using electrocardiograms (ECG) recorded during cardio-ankle vascular index (CAVI) measurement can serve as a practical substitute for conventional resting ECG-based HRV assessment. Methods and results This cross-sectional study enrolled 48 patients with diabetes and 20 healthy controls. HRV spectral indices were calculated from ECG recorded during both resting (3-min HRV) and CAVI measurement (CAVI-HRV). Agreement between HRV indices obtained under different conditions was evaluated by intraclass correlation coefficients and Bland–Altman analyses. Correlations between HRV parameters and clinical indices were examined. Participants with diabetes showed significantly lower HRV (especially high-frequency power), and reduced coefficient of variation of RR intervals. HF power of CAVI-HRV showed good agreement with 3-min HRV, whereas LF power showed only moderate concordance. HRV spectral parameters did not significantly correlate with severity of sensorimotor polyneuropathy. Conclusions HRV analysis performed during CAVI measurement reliably assesses parasympathetic function in diabetes. This approach may provide a convenient, accessible strategy for early CAN screening.