August 12, 2010

Studies Find High Risk Of Heart Problems In HIV-Positive Adults (AIDS 2010)


By Caitlin McHugh and Courtney McQueen
Published: Aug 11, 2010 6:21 pm

Researchers presented several studies at the 2010 International AIDS Conference in Vienna, Austria that evaluated heart function and heart disease in HIV-positive adults. Two studies found that even young, healthy people with HIV may show signs of heart problems; two additional studies showed that kidney disease and heart disease in people with HIV may be linked.

People with HIV can be particularly prone to heart disease and heart problems, with some studies estimating that heart disease causes a fifth of all deaths in people with HIV.

As a result, researchers are conducting studies to identify risk factors and how heart disease develops in HIV-positive adults.

Adults With HIV May Have High Rates Of Coronary Artery Narrowing

This pilot study examined 52 HIV-positive adults with a low risk for heart disease to determine the rate of coronary artery stenosis – narrowing of the arteries that bring blood to the heart muscle. Results showed that even in this low-risk group half of study participants had coronary artery narrowing.

Narrowing of the arteries restricts blood flow to the heart, which increases the risk for a heart attack. Since people with HIV are already at higher risk of heart problems, the researchers wanted to determine the rate of coronary artery narrowing in otherwise healthy people with HIV.

All the study participants were classified as low risk for heart disease based on their age, cholesterol levels, weight, and other factors. None had previously shown any signs or symptoms of heart problems.

In addition, the majority of participants (73 percent) had a low viral load (amount of virus in the blood) of 50 copies per milliliter or less.

Testing revealed that half of the participants in the study had coronary artery narrowing. Of these, half were mild cases and the rest were moderate or severe. A total of five study participants (10 percent) were diagnosed with severe artery stenosis.

The researchers could find no differences between participants in immune system functioning, or other medical tests, to explain who developed artery narrowing and who did not.

They concluded that all HIV-positive adults should be screened for heart disease regardless of risk factors or symptoms.

Fatty Liver Disease Is Associated With Heart Disease In People With HIV

This study was aimed at discovering whether fatty liver disease indicates heart disease in people with HIV.

Fatty liver disease is reversible and results from abnormal fat accumulation in liver cells. It can be caused by excessive drinking or obesity, but can also be caused by lipodystrophy, an abnormal change in the body’s fat distribution that is a common side effect of some antiretroviral medications.

Most of the 204 HIV-positive adults, with an average age of 44 years, did not have other HIV-related diseases.

Despite the age and relative health of the participants in the study, researchers found that over a third (36 percent) had heart disease. They also found that fatty liver disease was associated with heart disease.

Older age, high blood pressure, and possibly Ziagen (abacavir) use were also linked to heart disease.

The researchers concluded that fatty liver disease may indicate heart disease in people with HIV. They recommend that HIV-positive adults with fatty liver disease be tested for heart disease and consider discontinuing the use of Ziagen to prevent further heart problems.

Abnormal Heart Blood Flow Linked To Poor Kidney Function And Low CD4 Count

Another study examined patients in the HIV Clinic Database who had undergone a stress test, which determines the amount of blood flowing to the heart, between 2004 and 2009. Results showed that abnormal heart blood flow is linked to poor kidney function and low CD4 counts.

When heart blood flow is abnormal not enough oxygen reaches the heart, which increases a person’s risk of heart disease and heart attack. Abnormal heart blood flow often manifests as chest pain.

For the study, researchers compared 20 HIV-positive patients who had stress tests revealing abnormal blood flow to 20 HIV-positive patients of the same age and sex with normal tests.

The comparison showed that there were no significant differences in age, sex, body mass, heart disease risk factors, or antiretroviral therapy between the two groups.

However, the results did show that patients with poor kidney function and low CD4 counts (350 cells per microliter or less) were more likely to have abnormal blood flow as measured in the stress tests.

As a result of their findings, the researchers advise people with HIV who have kidney disease and a low CD4 count to work to reduce their risk of heart disease.

This includes avoiding cigarettes and alcohol, reducing blood pressure and cholesterol, exercising, and losing excess body fat.

Kidney Disease Linked To Recurrent Hospitalization In HIV-Positive Patients With Heart Failure

A study at St. Luke’s-Roosevelt Hospital Center in New York examined factors contributing to frequent hospitalization in HIV-positive patients with heart failure.

A total of 77 patients were followed over the course of one year. Researchers recorded factors such as viral load, CD4 count, heart and kidney function, blood pressure, and number of hospitalizations.

The results revealed that chronic kidney disease was the only factor that was significantly associated with frequent hospitalization.

Researchers determined that 61 percent of the patients had chronic kidney disease and that kidney disease nearly doubled the number of yearly hospital visits necessary.

They concluded that kidney disease is the primary factor responsible for recurrent hospitalizations in HIV-positive adults with heart failure.

For more information, please see the AIDS 2010 conference website.

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