How Marijuana Use Affects HIV Testing and Care

Ethan Morgan
Ethan Morgan

One of the key goals for any provider of HIV care is getting patients from diagnosis to being virally suppressed on treatment. However, we tend to see a drop off of patients along the HIV care continuum. A recent study set out to examine whether marijuana use affected a patient's progress toward viral suppression. Terri Wilder spoke with Ethan Morgan, who presented a poster on marijuana use and the HIV care continuum, at CROI 2015 in Seattle, Washington.

Tell us a little bit about your study.

We're initially interested in looking at how marijuana affects the HIV care continuum cascade, especially given that there's a decriminalization of marijuana in many states in the U.S. right now. HIV continuum of care is a measure of -- once you're diagnosed HIV positive -- several stages, which go through: linked to care; retention in care; adherent in care; and suppressed in care; to virally suppressed, which is the end goal for anyone who is HIV positive.

We have a sample of 623 young black men who have sex with men [MSM], from the South Side of Chicago. From there, we performed several metrics. We had a very long survey. We got blood spotting. We performed in-house HIV testing and counseling. So our outcomes of interest, what we were interested in measuring, is how marijuana affects the continuum of care.

The model we used here: We have all those continuum measures as our outcome. And then the predictor of interests in this case is, of course, marijuana use. Our baseline is never users -- people in the past 12 months who have never used marijuana -- and then intermittent users, which is any use of marijuana, up to and including at least once a week. Our heavy users are defined as using at least once per day.

In that, we looked at the outcome of marijuana use on each of those cascade variables. What we find is that the use of marijuana actually does not affect being linked to care, retained in care, adherent or suppressed.

"Once you're in the continuum of care it doesn't actually matter how much you use marijuana. The issue is entering the cascade in the first place."

In other words, once you're in the continuum of care it doesn't actually matter how much you use marijuana. The issue is entering the cascade in the first place.

Heavy marijuana users are about 430% more likely to not know they are HIV positive in the first place. Intermittent users are slightly less; they're about 270% more likely to have no idea they're HIV positive in the first place.

What we find is that the issue in the intervention that we want to target toward is, those that use marijuana, either intermittently or heavily, we want to get them into more HIV testing, and more regular HIV testing, to determine whether or not they're positive in the first place.

We can get them in the continuum of care. And once they're in the continuum of care, it appears as though intermittent or heavy use doesn't actually affect whether or not you are adherent and then, at the end, virally suppressed -- which is good, because we want everyone to be virally suppressed. It's just that we need to target more individuals, especially in our cohort, the young black MSM; we need to get more of them testing on a regular basis.

Is there information that says that young black MSM are more likely to use marijuana?

Yes, there's a lot of research. A lot of recent research shows that, especially with men under 30, in general -- not even just black MSM -- it shows that they tend to use marijuana more than any other drugs. Men over 30 tend to use the more classic HIV-related drugs: intravenous drugs, poppers, methamphetamines.

We did a pilot study of this in which, initially, with a much smaller sample, about 200 guys, we found a really high percentage of marijuana use. So when we designed this study, we found about 32% of our guys in this study use marijuana heavily, using it at least once per day. Almost no one in this study uses methamphetamines or psychedelics, or prescription drugs. That's why, because of the pilot, we targeted specifically toward that in this study.

You also noted that you found a roughly equal percentage of depression and anxiety among intermittent marijuana users. And among heavy marijuana users, you found a greater proportion of anxiety. Is that something that needs to be on providers' radars when their patients disclose to them, "I use marijuana"?

Right, it's something that should definitely be on the radar. In this case, we have a young cohort of men and they're pretty highly educated, compared to a lot of black MSM on the South Side of Chicago. In this case, we don't find a significant difference in depression and anxiety among our cohort. Something we didn't look at, which would be nice to look at in future waves, is whether or not any of these men are using marijuana for alleviation of HIV symptoms -- which may play a big role in this, and why we don't actually see a difference.

But you're right. In this case, we absolutely need to be paying attention to depression and anxiety to see how that affects it. Because if you're using marijuana because of depression and anxiety, it may affect the cascade more than if you're actually using it to alleviate symptoms. But that's not something we looked at here. So we need to look at that further in the future.

So if we know individuals are smoking marijuana, we should get them to test for HIV?

Yeah, if you know they're smoking marijuana, absolutely, get them to test. In states where it's decriminalized, like Washington and Colorado, that's easier because people are more willing to tell you if they're smoking marijuana.

We recruited specifically from clinics, community venues, online venues, schools, treatment programs and LGBT venues. So, in that case, it can be more of a general message. Like, you don't need to tell us what you're doing; but if you're smoking marijuana, just be aware and communicate more that you need to get tested regularly. Because the more you tell someone about it, the more they're just going to understand that and get it in their head to just get tested.

"There's a stigma around \[HIV testing\], in the first place. Then, if you add in the marijuana part of it, it's clearly causing, for some reason, less testing."

I think, in a lot of cases, it's just talking about testing more, especially with this cohort of men. There's a stigma around it, in the first place. Then, if you add in the marijuana part of it, it's clearly causing, for some reason, less testing.

Does Illinois have an HIV testing law? For example, in New York state, there is an HIV testing law that was implemented in 2010 that says all medical providers must offer people between the ages of 13 and 64 an HIV test. Now, that doesn't mean they have to accept it; it just means the medical provider has to offer it. Is there a similar mandate in Illinois?

No. As far as I know, there's no mandate. So this could be a very important piece, where it may be something that needs to be mandated and offered.

It's pretty widely available in Chicago, even given that this sample is from the South Side and there's not as much testing as, say, on the north side, which is a big issue. I think it's something that definitely can play a role in whether or not it should be mandated -- which it probably should.

This transcript has been edited for clarity.

Terri L. Wilder, M.S.W., is a director of HIV/AIDS education and training in New York City.