Aspirin in the 21st century

Aspirin use in individuals with HIV

Dr Andrew Freedman – Cardiff University, Cardiff, UK

What brings you here to the meeting?

I’m going to be giving a talk on HIV and aspirin which is a relatively underdeveloped area but one with increasing interest. We know that aspirin is relatively underused in people with HIV infection but there is increasing interest in using it in addition to antiretroviral therapy.

Why is there interest in using aspirin in patients with HIV?

We have very good antiretroviral therapy now and prognosis in HIV infection is extremely good and most patients will have a near normal life expectancy. But we do know that patients, even well controlled on antiretroviral treatment, have an increased incidence of non-infective comorbidities, particularly vascular disease but also malignancies, liver disease, renal disease and also neurological complications. There has been a lot of work done looking into the mechanisms of vascular disease and these other complications. It does seem although they’re almost certainly multifactorial that part of the problem is a chronic inflammatory state with heightened immune inactivation. There have been some preliminary studies done looking at the role of aspirin in perhaps reducing that chronic inflammation.

What about using other anti-inflammatory agents other than aspirin?

There have really been no trials in HIV of other agents and there have been very few, in fact, in aspirin. There has been one short-term study, just a week long course of aspirin in patients with HIV and HIV negative controls which have shown some laboratory measures that suggest that it might have a role to reduce platelet activation and also reduction in a soluble CD14 which is a marker of monocyte macrophage activation. Those studies, those short-term studies, suggest that aspirin may have a role alongside antiretroviral therapy.

Can you give a short overview of some of the research you discussed?

I’ve mentioned the short-term study that was done. There are now in progress, actually, some longer term studies and we’re still waiting for data. So there isn’t very much more at the moment but there has been a study by that same group in New York who gave aspirin for a week, they’ve done a three month study looking at different doses of aspirin and they’ve looked at the primary endpoint again being soluble CD14, this marker of monocyte activation. They’ve done all the studies but the data analysis has yet to be completed so we’re waiting for that. There’s another trial which is ongoing as well in the States comparing aspirin and also a statin in patients, so one or the other but not both, in patients with HIV and that’s a slightly longer study, a nine month study. Again the trial is underway but we don’t have the data yet. So there is no firm proof yet that aspirin is beneficial but there’s certainly some good preliminary indications that it may well have a role. What we do know is that aspirin is relatively underused in patients with HIV infection. There have been two studies, again both from the States, which have shown that compared to HIV negative subjects these are patients with vascular risk factors who, according to guidelines, should be taking aspirin. A smaller proportion of patients with HIV are taking aspirin than actually the general population and there are probably a number of reasons for that. But certainly aspirin does not currently appear in any HIV specific guidelines for treatment.

Should all patients with HIV be prescribed low-dose aspirin?

I don’t think we can say that yet, I think we have to wait for more data but certainly it may well have an important role to play.

Do you have anything further you would like to add?

I mentioned that malignancy, there is an increased incidence of malignancy in patients with well controlled HIV infection. Of course the data that is emerging about the role of aspirin in prevention of malignancy may well be relevant to HIV patients as well.

Are there particular types of cancer that patients with HIV get and that aspirin might help allay?

There was a slight increase in a number of different cancers. The classic AIDS associated cancers, lymphoma and Karposi’s sarcoma, the incidence of those goes down when patients take antiretroviral treatment but nevertheless there’s a small but significant increase in the incidence of a wide range of cancers and the mechanism isn’t fully understood.

What is your take-home message?

I think the take-home message is at the moment that aspirin is relatively under-prescribed for patients with HIV infection, particularly for the vascular risk factors that we know they have. But the emerging data suggests that there may be a role of aspirin in addition to antiretroviral therapy to reduce the chronic inflammatory state which in turn may reduce some of the other non-infectious complications of HIV.