Correlation of Cardio–Ankle Vascular Index With Accelerated Photoplethysmography and Risk Factors: A Retrospective Chart Review

The cardio-ankle vascular index (CAVI) and accelerated photoplethysmography (APG) are noninvasive methods for assessing arteriosclerosis, but differences in measurement principles and anatomical targets may lead to discrepancies in reported values. This study evaluated the correlation between CAVI and APG and identified factors contributing to inconsistent results. A retrospective chart review was conducted for patients who underwent both examinations between 2021 and 2023. Right and left CAVI and APG wave types were classified as normal, borderline, or abnormal, and participants were grouped (G0-G3) based on combined results. Clinical data including demographics and medical history were analyzed. Pearson correlation analysis showed statistically significant but modest positive correlations between CAVI and APG in all participants (Right: r = 0.261; Left: r = 0.235; both p < 0.001). In males, correlations were slightly stronger (Right: r = 0.298; Left: r = 0.280; both p < 0.001). Receiver operating characteristic (ROC) analysis demonstrated only modest discriminatory ability of APG for identifying high arterial stiffness defined as CAVI ≥ 9 (AUC 0.59-0.66). Subgroup analysis revealed that age was the only significant factor associated with abnormal results in males. In females, age and diabetes were associated with abnormal findings in both CAVI and APG, while age and hypertension (HTN) were associated with abnormal CAVI despite normal APG. Although CAVI and APG reflect different aspects of vascular health, they provide complementary information in clinical evaluation. Sex-specific risk factors, particularly age, diabetes, and HTN in females, should be considered when interpreting these vascular assessments.