Does HIV raise the risk of sudden cardiac death?

Sudden cardiac death refers to an abrupt loss of heart function and is different from a heart attack.

Dave Yasvinski 4 minute read September 8, 2021
HIV heart health

Among people with HIV, those who have a compromised immune system, appear to have a higher risk of cardiovascular disease. Getty

A new study has found that people with HIV may be more likely to suffer sudden cardiac death, particularly those who do not have the condition under control or who have other risk factors for heart disease.

The work, which appears in the Journal of the American Heart Association, builds on previous research that discovered people with HIV faced four times the risk of sudden cardiac death— expanding the scope of study to a national level and factoring in viral load and other potential risk factors. “People living with HIV are already known to have a higher risk of heart attack, stroke, heart failure, blood clots in the lungs and peripheral artery disease,” said Matthew S. Freiberg, lead author of the study and a professor of medicine at Vanderbilt University School of Medicine in Nashville.

“We know that among people with HIV, those who have a compromised immune system, for example a low total CD4+ T cell count, they seem to have a higher risk of cardiovascular disease than those who have high CD4+ T cell counts. It is unclear if a compromised immune system is a risk factor for sudden cardiac death.”

Sudden cardiac death refers to an abrupt loss of heart function — usually caused by a problem in the heart’s electrical system — that prevents the vital organ from circulating blood throughout the body. It is not the same thing as a heart attack, which is generally caused by a blockage in the flow of blood to the heart, although heart attacks have been known to trigger sudden cardiac arrest. Roughly 35,000 cardiac arrests occur every year in Canada, most in public places or in residences, with few patients surviving the experience.

For the study, researchers analyzed data from the Veterans Aging Cohort Study (VACS), a long-term, ongoing project that follows veterans with and without HIV (at a ratio of two uninfected patients for every HIV-positive patient), matching participants by age, sex, race/ethnicity and the medical facility they receive care. The 144,000 veterans included in VACS had an average age of 50 at enrollment, 97 per cent were male and 47 per cent were African American. All participants — 30 per cent of which had an HIV diagnosis — were followed from April 2003 to December 2014. By the median follow-up at the nine-year mark, 3,035 patients had suffered sudden cardiac death; 777 (or 26 per cent) were HIV positive.

After accounting for risk factors, including the presence of heart or kidney disease and cocaine or alcohol dependence, researchers found the risk of sudden cardiac arrest was 14 per cent higher in people with HIV. However, it was not any higher in HIV patients who had healthy levels of infection-fighting CD4+ T cells or low levels of the HIV virus in their blood. Risk of sudden death increased with the presence of each additional risk factor, including existing cardiovascular disease, hypertension, smoking, hepatitis C infection, alcohol dependence, COPD and amenia — regardless of HIV status.

HIV positive participants with low levels of CD4+ T cells over time — a sign of a progressing condition and a compromised immune system — faced a 57 per cent higher risk of sudden cardiac arrest. This number jumped to 70 per cent in participants whose blood tests showed antiretroviral therapy was not successful at reducing their HIV viral load.

“Addressing risk factors related to both cardiovascular disease and HIV is essential to prevent the higher rates of sudden cardiac death in people with HIV,” said Zian H. Tseng, senior author of the study and a professor of medicine in residence, Murray Davis Endowed Professor at the University of California, San Francisco.

“Clinicians should consider screening for specific warning signs of sudden cardiac death such as fainting or heart palpitations. And, if indicated, clinicians should request additional testing such as echocardiograms or continuous rhythm monitoring.”

The study had several limitations, including the usage of a large proportion of male participants, which may make findings less generalizable across genders. Also, autopsies — the definitive way of diagnosing death by sudden cardiac arrest — were not often available to researchers, presenting the possibility that some participants may actually have died from non-cardiac causes, such as a drug overdose, blood clot or stroke. The HIV positive participants also had more scar tissue in the heart muscle, a factor that may make fatal arrhythmias more likely.

Still, the findings highlight the need for heightened attention among HIV positive patients, with regards to heart health and other concerns. Tseng said. “In addition to HIV and cardiovascular risk factors, it is important for health care professionals to screen for and treat substance use disorders especially in people with HIV because they have a three times higher rate of overdose deaths presenting as cardiac arrest in our previous research.”

For more information on HIV and AIDS, support or to connect with other patients, visit CATIE or the Canadian AIDS Society.

Dave Yasvinski is a writer with