Asymptomatic IHD is characterized by reduced blood supply to the heart muscle that hasn’t yet caused symptoms like chest pain (angina) or decreased exercise tolerance. Its usual underlying cause is arteriosclerosis and typical risks include older age, smoking, high cholesterol levels, diabetes and high blood pressure. Some studies have suggested that HIV and/or antiretroviral therapy may further increase the risk.  

ECG evidence of asymptomatic IHD was documented in 536 (10.9 percent) of 4,831 HIV-positive volunteers participating in SMART, a clinical trial comparing immediate and deferred antiretroviral therapy. According to report author Andrew Carr, MD, of the University of New South Wales in Sydney and his colleagues, the prevalence usually ranges from 1 to 9 percent in other cohorts involving HIV-negative volunteers.

Asymptomatic IHD was most frequently found in older HIV-positive patients and in those with a long-standing history of high blood pressure. Study participants in Europe and possibly Asia also appeared to be at a higher risk for IHD than their North American counterparts. Compared with other studies, such as the D:A:D cohort, SMART did not find an association between IHD and smoking history, cholesterol levels or antiretroviral therapy.

Due to a major limitation of the study—it required ECGs only at the start of the study—firm conclusions were not possible. The authors note, however, that IHD greatly increases the risk of a heart attack and sudden death and should therefore be studied more extensively in HIV-positive patients, including a closer look at possible risk factors and causes.