A recent study uses results of advanced coronary vessel imaging to compare the presence and extent of subclinical atherosclerosis in HIV-infected and non-infected men.
The extended life span now afforded patients with HIV infection that is controlled by antiretroviral therapy (ART)1 creates a population with its own set of emerging health issues. As these patients age, the incidence of chronic noninfectious-related complications is projected to increase. Coronary artery disease (CAD) is a primary example.
It has been approximately a decade since initial reports of an increased risk of atherosclerosis among patients being treated for HIV infection.1 Until recently, however, the data on this risk have been conflicting. Advances in imaging such as CT scan measurements of coronary artery calcium (CAC) levels and ultrasound measurement of carotid intima-media thickness now make it possible for researchers to objectively assess subclinical atherosclerosis in HIV-infected patients.
In a study published this month in the Annals of Internal Medicine, Post and colleagues2 examined the Multicenter AIDS Cohort Study (MACS), an established study that includes a demographically matched control group. In HIV-infected and non-infected men they examined the presence and extent of CAC on noncontrast cardiac CT and using coronary CT angiography examined the presence of any plaque; noncalcified, mixed, or calcified plaque; or stenosis.
In the study, a total of 1001 men had non-contrast CT scan results available, and 759 of those also had had coronary CT angiography results.
Interestingly, the investigators found a greater prevalence and extent of coronary atherosclerosis on CT angiography in HIV-infected men than in uninfected men. The difference in the prevalence and extent of noncalcified plaque persisted after adjustment for other atherosclerosis risk factors.
The investigators also found a correlation between the presence of coronary artery stenosis greater than 50% and low nadir CD4 T-cell count and the length of time they were receiving highly active ART. These findings suggest an increased risk of cardiovascular events in HIV-infected patients. This is consistent with the results of previous studies suggesting an association between innate immune activation and noncalcified plaques, which may contribute to higher rates of myocardial infarction in HIV-infected patients.3
The important take-home message here is that all physicians caring for HIV-infected patients should be vigilant in addressing well-established risk factors for CAD such as smoking, hypertension, dyslipidemia, and diabetes mellitus in HIV-infected patients.3
1. May MT, Sterne JA, Costagliola D, et al; Antiretroviral Therapy (ART) Cohort Collaboration. HIV treatment response and prognosis in Europe and North America in the first decade of highly active antiretroviral therapy: a collaborative analysis. Lancet. 2006;368:451-458. http://www.ncbi.nlm.nih.gov/pubmed/16890831
2. Post WS, Budoff M, Kingsley L, et al. Associations between HIV infection and subclinical coronary atherosclerosis. Ann Intern Med. 2014;160:458-467. http://www.ncbi.nlm.nih.gov/pubmed/?term=Ann+Intern+Med.+2014%3B+160%3A458.-67
3. Currier JS, Stein JH. HIV and atherosclerosis: moving from associations to mechanisms and interventions. Ann Intern Med. 2014;160:509-510. http://annals.org/article.aspx?articleid=1852877