Background: Obesity blunts the association of cfPWV with BP, at least in youth. We assessed the impact of BMI in the relationship between carotid artery function (CAF) and central BP.

Methods: Stiffness index (β), Elastic modulus (Ep), Arterial Compliance (AC) and local PWV (PWVβ) were measured at the common carotid arteries by echo-tracking (Aloka prosound alpha 10), and central BP was assessed with the SphygmoCor device. Patients were classified into 3 groups according to BMI (<25 normal weight; ≥25-<30 overweight; ≥30 obesity). Linear regression models, Pearson’s correlation coefficient and ANCOVA models (age, gender, heart rate and central PP as covariates) were performed.

Results: 222 patients (mean age 42.8 ± 14.2 years; 93 (42%) women; mean BMI 26.6 ± 4.4; 139 (62.6%) hypertensives, 104 (74.8%) under treatment). BMI categories: 85 (38.3%) normal weight, 88 (39.6) overweight, 49 (22.1%) obesity.

Age, HR,central PP showed significant positive association with CAF parameters. BMI categories and gender were not significantly associated with CAF parameters, except for overweight with PWVβ (p-value 0.02). There was no significant difference in β, Ep, AC and PWVβ between BMI groups after adjusting by covariates. Pearson’s correlation coefficient between central SBP and CAF parameters was significantly lower if BMI≥25 (â: 0.46, 0.19, 0.13; Ep: 0.69, 0.43, 0.3; AC: −0.48, −0.37, −0.31; PWVâ: 0.66, 0.48, 0.36 for normal weight, overweight and obesity, respectively; p-value for overweight<0.001, p-value for obesity<0.05).

Conclusions: BMI categories are not closely related to CAF. BMI might blunt the increment of CAF parameters with rising central BP.