This Week in HIV Research: I Screen, You Screen, We All Screen for HPV-Related Cancers
As HIV care providers, are we screening our patients for anal or cervical cancer at the optimal time -- and using the most effective methods? This week, we investigate these questions as part of our brief tour of select recently published journal articles on HIV-related topics, which includes:
- Findings that associate anal cancer risk most strongly with certain CD4 count variables over time.
- A suggestion that anal pap smears be considered for women who have health risks associated with prevalent human papillomavirus (HPV) infection.
- Initial results from a switch study comparing E/C/F/TAF to ABC/3TC.
- Underwhelming findings from a study on the potential benefits of marijuana use among people living with HIV.
Read onward for more information regarding each of these research findings. To beat HIV, you have to follow the science!
Anal Cancer Risk Related to Nadir, Cumulative Time With Low CD4 Cell Count
Nadir and cumulative CD4 cell counts could be used to screen people living with HIV for a heightened risk of anal cancer, a model published in Clinical Infectious Diseases concluded.
Researchers analyzed data on 102,777 people from 21 cohorts in the parent North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) study. Most participants (85%) were men; likewise, 96% of the 492 people who were diagnosed with anal cancer were male. Study authors constructed lagged-time models to explore the extent to which changes in a person's CD4 or HIV RNA levels over time were predictive of anal cancer risk.
Of the models they explored, researchers found two that were most closely associated with anal cancer risk:
- A person's nadir CD4 count stretching as far back as 8.5 years.
- The proportion of time a person spent with a CD4 count below 200 between 4.5 and 8.5 years ago.
A low CD4 nadir and a long time with low CD4 count indicate severe, prolonged immunosuppression, which may contribute to the development of high-grade squamous intraepithelial lesions, study authors hypothesized. They suggested monitoring nadir and cumulative CD4 counts to target anal cancer prevention in people living with HIV.
Women With High-Risk Cervical HPV May Benefit From Anal Pap Smears
An anal pap smear should be considered for women who have high-risk human papillomavirus or cervical high-grade intraepithelial lesions, Susan E. Bennett, M.D., an associate professor of medicine at Harvard Medical School, recommended in a commentary in Clinical Infectious Diseases.
Her comments were based on a pilot study published in the same issue involving 75 women, 69% of whom were living with HIV. The study found a correlation between anal high-grade squamous intraepithelial lesions and high-risk cervical HPV, likely because the virus infects the entire perineum. It also showed that 85% of study participants with anal dysplasia had HPV types that are included in the Gardasil-9 vaccine. Study authors found that hypermethylation of cervical DNA markers, a non-invasive technique, may identify women at risk for anal dysplasia, although they called for more research into methylation in this context.
Bennett, a primary care physician practicing at Massachusetts General Hospital, proposed more wide-spread HPV vaccination and better coordination of screenings between primary care providers and gynecologists, possibly using a universal medical record. "In order to accomplish that, we need universal access to health care that includes immunization against HPV through age 45 or beyond, regular screening cervical pap and/or HPV tests and for some anal pap testing," she advocated.
E/C/F/TAF Non-Inferior to ABC/3TC-Based Treatment in 24-Week Switch Study
Switching to elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF, Genvoya) single-tablet therapy was found to be non-inferior to remaining on an abacavir/lamivudine (ABC/3TC, Epzicom)-based regimen in a phase 3b study funded by Gilead Sciences, Inc., the manufacturer of E/C/F/TAF, that was published in AIDS.
All 274 participants were virally suppressed on an ABC/3TC-based regimen at baseline. They were randomized 2:1 to switch to E/C/F/TAF immediately (183 people) or after 24 weeks (91 people) for a total study period of 48 weeks. The current results are from week 24.
Virologic response was maintained by 93% in the new drug group and 98% in the prior regimen group. No study drug-related adverse events were reported in the ABC/3TC arm, but 18% of participants in the E/C/F/TAF arm experienced such events and 4% discontinued as a result. Participants on the single-tablet regimen reported higher treatment satisfaction (mean 23.7 on a 30-point scale) than those on the older regimen (mean 17.7). Eighteen participants discontinued before week 24 (15 in the immediate-switch arm and 3 in the delayed-switch arm).
Results show E/C/F/TAF to be efficacious and well tolerated with greater treatment satisfaction, study authors concluded.
Marijuana May Not Reduce Pain or Opioid Use, But Study May Be Underpowered
Among people living with HIV and chronic pain, marijuana use did not appear to improve pain levels or reduce opioid prescriptions, a small study published in Journal of Acquired Immune Deficiency Syndrome found.
Prior studies have shown that 20%-60% of people living with HIV use marijuana, compared to 8% of the general population. All 433 participants in this study -- 28% of whom reported using "nonmedical" marijuana during the three months preceding the index visit -- were in HIV clinical care in the U.S.
Both marijuana use and pain level were self-reported, with a median pain severity of 6.3 (on a scale of 1-10, where a higher number indicates worse pain) at the index visit and no median change during follow-up. Opioid prescription was defined as starting (8% of participants) or stopping (10%) that medication during the study period.
Study authors acknowledged the small sample size, noting "It is not possible to definitively determine whether we were underpowered to detect associations between marijuana use and pain/opioid outcomes, or whether these associations do not exist." They called for further research into the impact of marijuana use on pain in people living with HIV.