Patients with HIV infections are 4 1/2 times more likely to die suddenly from cardiac arrest than people without HIV, even if the virus is under control and they appear relatively healthy, according to a UCSF study.
The report, published Monday in the Journal of the American College of Cardiology, found that sudden cardiac death - which occurs when the heart unexpectedly stops beating - was the second-most common killer among HIV-positive patients. AIDS was the most common cause of death.
Researchers involved in the 10-year study believe no single cause is involved but say HIV patients and their doctors need to be more vigilant about being screened and treated for heart disease risks like high blood pressure and high cholesterol as their lives are being extended by antiretroviral drugs.
"Cardiac disease is a big issue as these people are living longer," said Dr. Zian Tseng, a UCSF electrophysiologist and lead author of the study. "HIV providers need to be aware of the risk of these patients dying suddenly."
Over the past two decades, the treatment of HIV has changed dramatically with the success of antiretroviral drugs. The medications can, in many people, suppress the virus to the point where it's undetectable in a patient's blood, and doctors have begun to see HIV infection as a chronic condition and not a death sentence.
Possible causesBut the trade-off is that the virus does damage over time, and perhaps so do the drugs used to treat it. Add to that the fact that HIV patients were slow to adjust to the idea that they could live much longer on the drugs, said Dr. Priscilla Hsue, director of the HIV Cardiology Clinic at San Francisco General Hospital and an author of the UCSF study.
They were reluctant to stop lifestyle choices that contributed to heart disease, such as smoking or heavy drinking, she said. But patients, and their doctors, are beginning to understand, and their thinking is changing, Hsue said.
"Now they're thinking, 'I could live another 25 years if I take care of myself,' " Hsue said. "And I'm really hammering on stop smoking, take blood pressure medication, watch your cholesterol."
The study looked at 2,860 HIV-positive patients who were treated in San Francisco General Hospital's HIV/AIDS ward from 2000 to 2009. In that period, 230 died - 57 percent of them from AIDS, 13 percent from sudden cardiac death, 11 percent from other natural diseases, and 19 percent from suicides, overdoses or unknown causes.
Notably, 86 percent of all cardiac deaths among those patients were sudden. In the general population, the number of sudden deaths is about half of those who have heart-related deaths.
High-risk patientsMore than half of the patients in the study who suffered sudden cardiac deaths had a history of smoking, heavy drinking or using drugs, and 80 percent of the patients who died suddenly had already been diagnosed with heart disease or had one or more risk factors. A third of the patients who died had reported chest pain, shortness of breath, heart palpitations or fainting at their final clinic visit.
Those are the types of patients that doctors should be on the alert for, researchers said.
Those patients didn't seem to have much worse symptoms of HIV disease than others with the virus. Their T-cell counts, a measure of the strength of the immune system, were only slightly below the average for all patients included in the study. And in half of the patients for whom laboratory results were available, the virus was undetectable in their blood at the time of death.
That suggests that it isn't the virus alone that's causing the heart problems, researchers said. Hsue and Tseng noted that HIV causes inflammation, even in mild cases, and that could affect the heart. Plus, some of the drugs used to treat HIV are known to interrupt the electrical activity of the heart, which could be a factor in sudden-death cases.
Focus for doctorsAnd there are the behavioral factors. "Smoking, obesity, exercise, substance abuse - we need to start making real good interventions for these," said Dr. Michael Horberg, director of HIV/AIDS at Kaiser Permanente. "As our patients are living longer and they're not dying from HIV, it means we need to pay close attention to these other very important risk factors for other illnesses."
Stu Smith, who has been treated for years at San Francisco General Hospital's HIV/AIDS clinic, said he and many other patients are coming to that conclusion on their own. He has been infected with HIV since 1988 and has had two blockages in his heart that were treated with stents.
He considers himself very lucky - for surviving so long with HIV, and for getting treatment for his heart condition.
"There's a tremendous amount of mortality right now (among HIV-infected people), starting in the late 40s and early 50s," said Smith, who is 71. "We're seeing a new kind of disease."