Hsue and her colleagues compared 68 HIV-infected individuals hospitalized with ACS between 1993 and 2003 with 68 randomly selected control patients with ACS but without HIV.

As well as being more than a decade younger than controls, the HIV patients were more likely to be male and current smokers and have low HDL cholesterol. They were less likely than controls, however, to have diabetes or hyperlipidemia, and their TIMI risk scores on admission were significantly lower. At angiography, the number of vessels with >50% restenosis was an average of 1.3 among HIV patients and 1.9 among controls; nevertheless, 53% of HIV sufferers undergoing PCI developed restenosis (15 of 29) compared with only 14% of controls (3 of 21; p=0.006).

"That's how we first realized that these patients were different," she says, "when they started coming back with higher rates of restenosis."

That's how we first realized that these patients were different, when they started coming back with higher rates of restenosis.

She believes that the increased rate of coronary events seen in HIV patients is likely due to side effects of HAART and inflammation as a result of HIV infection. "The drug treatments definitely play a role. Some HIV treatments can increase cholesterol and cause hypertension and glucose intolerance," she notes.

She says she does treat HIV patients with statins when necessary, and sometimes it is then necessary to change their HIV drug regimens, something done in conjunction with their HIV specialists. "For example, we might swap the older protease inhibitor lopinavir/ritonavir (Kaletra^®, Abbott), for a new one, atazanavir sulfate (Reyataz^TM, Bristol-Myers Squibb)," which appears to have minimal impact on lipids.

In the current study, 36 of the 68 HIV infected patients were receiving HAART at the time of onset of their ACS. Of these, 33 were receiving protease inhibitors and, compared with the 35 not receiving protease inhibitors, these patients were more likely to have a history of hyperlipidemia (13 vs 4, p=0.008) and to be taking cholesterol-lowering drugs (11 vs 2, p=0.004).

HIV patients are one group for whom we have high hopes for the drug-eluting stent.

But Hsue also thinks that chronic low-level inflammation in HIV patients may contribute to the high rate of restenosis seen. Her team has measured CRP levels in HIV patients and found higher levels than in noninfected individualsthese results are also due to be published in Circulation. She adds that high CRP levels in turn are predictive of higher restenosis rates. "HIV patients are one group for whom we have high hopes for the drug-eluting stent," she notes. She says drug-eluting stents are now routinely being used for PCI in her hospital, but that they have not yet placed one in an HIV-infected patient.

Hsue adds that HIV-infected patients "also have a high number of other risk factors, which physicians need to be aware of and address." For example, they are much more likely to smoke, and they are often taking testosterone and steroids, "and we don't know what the effects of these are."