This Week in HIV Research: Links in a Chain

Starting antiretroviral therapy while a person living with HIV (PLWH) and substance use disorder is hospitalized is associated with faster linkage to care, but not with long-term retention in care, a study published in Clinical Infectious Diseases showed.

HIV treatment was initiated in the hospital in 15% of 801 PLWH with substance use disorder (SUD); 65% of these initiations were among treatment-naive participants. Data came from across the U.S., with people in Southern U.S. hospitals less likely to start antiretroviral therapy in hospital than those elsewhere in the country.

Participants who began HIV treatment while hospitalized had their first outpatient HIV care visit after 29 days on average, compared to 54 days for those not starting treatment. However, 12 months later there was no difference in retention in care or viral suppression rates between the two groups.

Study authors theorized that provider concerns about treatment adherence among people with SUD may be to blame. Social determinants, such as lack of stable housing, may also play a role both in starting antiretroviral therapy and staying on it. “As we approach the ‘End of the HIV epidemic,’ it is critical to consider intensive, multifaceted, and integrated approaches addressing HIV and other co-morbidities including, mental health disorders, and social determinants of health to achieve optimal HIV outcomes among PLWH and SUD,” study authors concluded.

Recent crack cocaine use was significantly associated with higher HIV viral loads, but this was not true for other street drugs, an analysis published in AIDS showed. The findings for crack cocaine were independent of the level of exposure a person had to antiretroviral medications.

Researchers used data from 843 people who participated in 8,698 interviews between 2005 and 2018 as part of the ACCESS study. The other drugs considered were powder cocaine, opioids, methamphetamine, and cannabis. Substance use was self-reported, and researchers recorded antiretroviral “exposure” based on medication dispensation records, which they noted may not correspond to actual treatment adherence.

The association between crack cocaine use and viral load was dose dependent: more frequent substance use was associated with higher viral loads. Study authors hypothesized a biological mechanism between that particular drug and HIV disease progression. Such a potential interaction has been shown in ex-vivo studies.

Social determinants, such as housing instability, were also associated with unsuppressed viral loads. Study authors hypothesized that homelessness could be related to food insecurity, which in turn could cause a poor virologic response despite HIV treatment.

A cross-disciplinary coordinated HIV care program in Los Angeles County increased the probability that clinic patients would achieve viral suppression, but housing instability and other comorbidities dampened that success, researchers reported in Journal of Acquired Immune Deficiency Syndromes.

All 6,408 PLWH in the study were enrolled in the program because they met any of a range of criteria that suggested they were not solidly in the HIV care continuum, including having an unsuppressed viral load, going seven months or more without seeing an HIV medical provider, or being newly diagnosed with HIV. The intervention, called a Medical Care Coordination Program, involves teams that include a registered nurse, case worker, and a social worker with at least a master’s degree.

Overall, the likelihood of being virally suppressed rose from 0.35 to 0.77 during the first six months of program enrollment and was maintained for up to 36 months.

Care plans were individually tailored to address each participant’s specific needs; housing instability, stimulant use, and high depressive symptoms were all considered. Having one of these needs lowered the probability of viral suppression. However, after three years in the program, those with depressive symptoms had similar odds of viral suppression as participants without any comorbidity. (The same was not true for stimulant use or homelessness, however.)

The findings are consistent with a similar study in New York City, the study authors noted. Coordinated care programs help people achieve viral suppression, but people experiencing homelessness or taking stimulants need additional support, they concluded. They called for additional research to identify specific program components needed, and for targeted Ending the HIV Epidemic funds to help local health jurisdictions set up their own medical care coordination programs.

HIV incidence was relatively low among women in King County, Washington, who were diagnosed with a sexually transmitted infection (STI) between 2008 and 2018, researchers reported in AIDS. The findings highlight the heterogeneity of U.S. HIV demographics from area to area—and the need to dive more deeply into potential HIV risk factors when deciding whether to recommend pre-exposure prophylaxis (PrEP) to particular patients.

HIV diagnoses were reported among 16 of the 5,524 women in the study who had gonorrhea; 31 of the 37,273 women with chlamydia; and none of the 397 women with syphilis. Based on partner notification interviews, most women who tested positive for HIV had additional risk factors for seroconversion, such as sex work or injection drug use.

This study’s HIV incidence rates are lower than those in similar studies in Florida and Tennessee, but comparable to those in Louisiana.

U.S. guidelines consider any STI to be an indication for offering PrEP to a woman. But these findings show that the risk of HIV acquisition may differ by location and the specific STI, study authors wrote. Thus, PrEP may not be warranted in all cases. “Overall, our study, as well as prior reports, highlight the need for better data to help medical providers and health departments identify, which women are at high risk for HIV acquisition and might benefit from PrEP,” they concluded.