Vascular age calculation and equivalent risk factors in HIV-infected patients obtained from the D:A:D risk equation

Abstract

Background: Vascular age is a concept that represents the hypothetical age of the cardiovascular system and might be an alternative way of expressing the cardiovascular risk of a patient. The Data Collection on Adverse Effects of Anti-HIV Drugs Study (D:A:D) developed a cardiovascular risk equation from a population of HIV-infected patients, incorporating exposure to individual antiretroviral therapy drugs and traditional classic cardiovascular risk factors.

Objectives: The aim of this study was to determine the vascular age calculated from the D:A:D equation, for HIV infected patients.

Methods: Vascular age was calculated according to its definition by using the D:A:D equation. The Poisson regression model used in the D:A:D equation is an exponential model to calculate the vascular age to match the exponent of the equation with the factors of a patient with the exponent of a subject with controlled risk factors.

Results: We obtained an equation that allows calculating the vascular age of a patient considering cardiovascular risk factors listed in the same D:A:D equation. From the equation, we have built a table for easy calculation of the vascular age and a table of cardiovascular risk equivalents.

Conclusions: Vascular age is a new concept derived from Framingham risk tables that can be calculated with other risk scales, such as D:A:D for HIV patients. The calculation of vascular age in HIV patients could be a useful tool for communicating cardiovascular risk and to improve the control of modifiable risk factors.

Keywords: D:A:D equation; HIV; vascular age.