February 11, 2009
There's nothing like hearing the results of studies directly from those who actually conducted the research. In this interview, you'll meet one of these impressive HIV researchers and read her explanation of a study she presented at CROI 2009.
My name is Alexandra Oster. I work in the Division of HIV/AIDS Prevention at the U.S. Centers for Disease Control and Prevention. I'm going to summarize the study that we [are presenting at CROI 2009], which looked at the prevalence of cervical cancer screening among HIV-infected women in the United States.1
Let me start with a little bit of background. HIV-infected women are at increased risk of cervical disease. Cervical cancer and cervical disease are caused by human papillomavirus [HPV], and HIV-infected women are more likely to be infected with human papillomavirus. They're [also] more likely to have abnormalities in their cervix from that. These things can all progress to invasive cervical cancer.
Alexandra Oster, M.D.
We did this study to look at whether HIV-infected women were getting Pap smears as they're supposed to. We also wanted to understand what factors were associated with not getting screened for those women who said that they hadn't received a Pap smear in the past year.
We looked at data from a project called the Supplement to HIV/AIDS Surveillance. Those data were collected during 2000 to 2004, and there were a little over 2,400 women in the project during that time.
We found that [about] a quarter of the women reported that they hadn't had a Pap smear in the past year. That's probably an underestimate, because a lot of women think that they've had a Pap smear, when they've had a pelvic exam for some other reason. Or a lot of women may have thought that their Pap smear was in the past year, when actually it was longer ago than that. Nonetheless, we found that 23% did not report a Pap test in the year before they were interviewed.
We found that there were three main things that made women more likely to have not had a Pap smear. One was: They reported that their last pelvic exam was somewhere other than where they normally get HIV care. For these women, they may have gone to a gynecologist, or maybe they went to the emergency department for something, and had a pelvic exam at that time. We found that they had an increased risk of not having had their Pap smear. This could be for a couple of different reasons: When women go somewhere else for their Pap smear, it requires additional coordination. They need to get a referral from their doctor sometimes; they need to actually make another appointment and make it to that appointment -- maybe transportation is an issue. All of those things make it harder for women to get their Pap smear than if they got it at their normal HIV provider.
A second factor that was associated with not having received a Pap smear was increasing age. We found that as women got older, they were less likely to have had a Pap smear in the past year.
When you say older, what do you mean? Are these women who have reached menopause?
Actually, we saw it all along the continuum. Women who were 30 to 39 years old were less likely to have a Pap smear than those who were 18 to 29. Those who were 40 to 49 are even less likely, and those who were 50 or older were even less likely [than that]. So we're not talking about women who are 65 or 70 or 75; we're talking about all along the spectrum.
It's very important that women of all ages get Pap smears. We think there are some reasons for [why women are less likely to get a Pap smear as they age]: As you get older, you have other health issues, and your physician has to prioritize between different things. Women who are HIV infected have to prioritize between different things. But it is very important to continue to get that preventive health care screening.
The [third] factor that was associated with not having received a Pap smear was having a CD4 count less than 200. This is likely true because these women are sicker; they have other issues going on, and it's hard to prioritize.
What is the exact increased risk for HIV-infected women of developing a cervical abnormality? On your poster, I think you say 13% to 60% of HIV-infected women have cervical abnormalities.
It is far higher [than it is among HIV-uninfected women]. I don't have the number right offhand. Definitely, 13% to 60% have abnormalities when they have their Pap smear. Those abnormalities are more likely to persist, they're less likely to go away, and they're more likely to advance than in women who don't have HIV.
Of course, if women don't get Pap smears, they could get cervical cancer. Are we seeing a greater incidence of cervical cancer in HIV-infected women?
It's a bit hard to say; things have changed over the many years that we've been looking at the epidemic. But I would say that invasive cervical cancer is an AIDS-defining illness, so it's one of those things that's in the criteria for the definition of AIDS.
Could you tell me about the characteristics of the people that were included in the study? Tell me a little bit about their history of other sexually transmitted diseases (STDs).
Women who had reported that they had an STD in the past year were more likely to have received a Pap smear than women who reported that they didn't.
What are your guesses about that? Is it that those women might be more sexually active, and thus were more proactive about taking care of themselves, because they know that they put themselves at risk for other diseases?
I think it may be a combination of factors. Certainly, from the physician's point of view, [one factor] is that many sexually transmitted diseases are diagnosed by doing a pelvic exam. While you're doing a pelvic exam, it's easy to do a Pap smear at the same time. I think [that among] women who have sexually transmitted diseases, that raises awareness of the need to be alert to other women's health issues.
In terms of looking at the United States, were there any regions where women were less likely to get a Pap smear?
We didn't look at regional differences. We didn't have a random sample from the entire United States; we had women from 18 different states, but it wasn't random, so we can't draw generalizations about different regions of the country.
Did you look at data about anal Pap smears?
We didn't, unfortunately. But that's an important area to continue doing research in.
Coming out of this study, do you have any recommendations regarding cervical cancer screening?
We came out with a few recommendations as a result of this study. I think there are two big areas where we can try to improve the rates of cervical cancer screening among HIV-infected women. One of those is through education, and one of those is through system change.
Let me start with education. First of all, educating HIV care providers about the importance of providing annual Pap smears to every HIV-infected women [is key]. But it's especially [true among] those three groups that I mentioned that aren't getting their annual Paps as well: those who are getting a pelvic exam elsewhere, those who are [older] and those who have a CD4 less than 200.
Second of all, I think we need to educate primary care providers, as well as gynecologists, who may not do HIV care about the differences in recommendations for women who are infected with HIV. As I mentioned, HIV-infected women need to continue getting an annual Pap smear every year, forever. Whereas in HIV-uninfected women, primary care providers may be able to reduce the frequency of screening or stop screening at a certain age. So it's important that primary care providers understand the differences.
Isn't the current recommendation for HIV-uninfected women to be screened for cervical cancer every two years?
Actually, it's a little bit more complicated than that. For HIV-negative women, they may be able to cut to every three years, if they're low risk and they've had three negative Paps in a row. But that is not the case for HIV-infected women.
The last recommendation, in terms of education, would be educating HIV-infected women, so that they know that it's very important to get an annual Pap smear, and they can be on top of it as well. Everyone really needs to be in the loop and working towards this.
The second thing that I mentioned was system change. I mentioned that one of our findings was that women who were getting their pelvic exams [from someone other than their HIV health care provider] are less likely to get cervical cancer screenings. That suggests that if you incorporate gynecologic care into the HIV care, those things will run more smoothly, and women will be more likely to get screened. At the system level, trying to integrate HIV and gynecologic care may help to improve cervical cancer screening.
Any next steps? Are you going to continue looking at this population?
I think the next step is to publish these results, and try to get them out there so HIV care providers, gynecologists and policy makers can all see the important issues that go into improving cervical cancer screening -- and act on that.
Thank you very much.
This transcript has been lightly edited for clarity.