Symmetric Ambulatory Arterial Stiffness Index and 24-h Pulse Pressure in HIV Infection: Results of a Nationwide Cross-sectional Study

Objective: HIV infection has been associated with increased cardiovascular risk. Twenty-four-hour ambulatory blood pressure (BP) is a more accurate and prognostically relevant measure of an individual's BP load than office BP, and the ambulatory BP-derived ambulatory arterial stiffness index (AASI) and symmetric AASI (s-AASI) are established cardiovascular risk factors.

Methods: In the setting of the HIV and HYpertension (HIV-HY) study, an Italian nationwide survey on high BP in HIV infection, 100 HIV-infected patients with high-normal BP or untreated hypertension (72% men, age 48 ± 10 years, BP 142/91 ± 12/7 mmHg) and 325 HIV-negative individuals with comparable age, sex distribution, and office BP (68% men, age 48 ± 10 years, BP 141/90 ± 11/8 mmHg) underwent 24-h ambulatory BP monitoring.

Results: Despite having similar office BP, HIV-infected individuals had higher 24-h SBP (130.6 ± 14 vs. 126.4 ± 10 mmHg) and pulse pressure (49.1 ± 9 vs. 45.9 ± 7 mmHg, both P < 0.001), and a lower day-night reduction of mean arterial pressure (14.3 ± 9 vs. 16.3 ± 7%, P = 0.025). Both s-AASI and AASI were significantly higher in HIV patients (s-AASI, 0.22 ± 0.18 vs. 0.11 ± 0.15; AASI, 0.46 ± 0.22 vs. 0.29 ± 0.17; both P <0.001). In a multivariate regression, s-AASI was independently predicted by HIV infection (β = 0.252, P <0.001), age, female sex, and 24-h SBP. In HIV patients, s-AASI had an inverse relation with CD4 cell count (Spearman's ρ -0.24, P = 0.027).

Conclusion: Individuals with HIV infection and borderline or definite hypertension have higher symmetric AASI and 24-h systolic and pulse pressures than HIV-uninfected controls matched by office BP. High ambulatory BP may play a role in the HIV-related increase in cardiovascular risk.