Improved assessment of arterial stiffness using corrected cardio-ankle vascular index (CAVI₀) in overweight adolescents with white-coat and essential hypertension

Arterial stiffness is a marker of vascular damage. Although adiposity increases cardiovascular risk, the relationship between paediatric overweight and arterial stiffness is unclear. The study aimed to evaluate the simultaneous effect of hypertension and overweight on arterial stiffness using cardio-ankle vascular index (CAVI) and related novel, theoretically blood pressure (BP)-independent, index CAVI₀. CAVI and CAVI₀ were measured in 140 adolescent boys (16.0 ± 1.9 years) divided into age-matched groups: normal-weight normotensives, overweight normotensives, overweight white-coat hypertensives, and overweight essential hypertensives. Overweight normotensives had significantly lower CAVI and CAVI₀ compared to normal-weight normotensives (4.81 ± 0.64 vs. 5.33 ± 0.66, p < .01; 7.10 ± 0.99 vs. 7.81 ± 1.00, p < .01, respectively). CAVI and CAVI₀ in overweight essential hypertensives showed no significant difference compared to normal-weight normotensives and were significantly higher compared to overweight normotensives (5.32 ± 0.77 vs. 4.81 ± 0.64, p < .01; 7.77 ± 1.19 vs. 7.10 ± 0.99, p < .01, respectively). CAVI, but not CAVI₀, was associated positively with diastolic pressure (0.022 mmHg^-1, p = .002) and negatively with pulse pressure (-0.022 mmHg^-1, p = .001), and it was significantly higher in overweight white-coat hypertensives compared to overweight normotensives (5.20 ± 0.63 vs. 4.81 ± 0.64, p < .05). The lowering effect of overweight on arterial stiffness indexed by CAVI and CAVI₀ in hypertensive adolescents seems to counterbalance the early arteriosclerotic effect of essential hypertension. The increase in CAVI, but not CAVI₀, in overweight white-coat hypertensives could be attributable to residual BP dependence of CAVI, which is not present in CAVI₀. Under certain conditions, CAVI₀ may offer a clinically relevant improved assessment of arterial stiffness superior to CAVI.