This post was updated May 21 at 10:29 p.m.

Researchers from UCLA and Northwestern University found that sibling support can act as an external motivator for Latino sexual minority men to take HIV prevention measures.

The National Institutes of Health-funded study – titled “Entre Herman@s,” or Between Siblings – was initiated in 2020 by Homero del Pino, an adjunct associate professor in the Department of Psychiatry and Biobehavioral Sciences at the UCLA David Geffen School of Medicine. Del Pino said he was inspired by research on how family rejection impacted LGBTQ+ individuals, which made him realize there was little research on the impact of family reconciliation, especially among the Latino LGBTQ+ population.

“Pick any disease – I bet you there will be a Latino, family-based intervention for it, like mammogram-seeking behaviors, diabetes management, substance use reduction, physical abuse and HIV prevention,” del Pino said. “But when you look at Latino gay men, it’s as if we crawl out of a rock. The number of family-based HIV prevention for Latinos is almost zero.”

As a gay Latino man himself, del Pino said the support he received from his siblings encouraged him to examine the role of sibling dynamics in HIV prevention. The study focused specifically on the use of preexposure prophylaxis, or PrEP, because the researchers were initially interested in the limits to which heterosexual siblings could discuss using the medication, del Pino added.

PrEP prevents HIV from replicating in the body after exposure, said Dr. Raul Macias Gil, an infectious diseases specialist at Harbor-UCLA Medical Center. He added that PrEP can be taken as a daily oral pill or a monthly injection.

However, del Pino said misunderstandings about PrEP’s side effects, coupled with the perception that taking PrEP implies promiscuity, could decrease people’s willingness to use the medication.

Another barrier relating to the Latino population was immigration status, Macias Gil said. He added that he previously had a patient without legal status who was diagnosed with syphilis and at risk for other sexually transmitted infections such as HIV.

“He thought that he was not eligible for PrEP because he doesn’t have a legal status in the U.S.,” Macias Gil said. “That’s something that a lot of our patients face. This is really sad to see, that patients still are afraid of requesting treatment for health care.”

​​To counter these barriers, siblings can be a trusted resource to reduce a patient’s worries about getting treatment, said Juan Zapata, one of the study’s co-authors and a research assistant professor of medical social sciences at Northwestern University. The more familiar a group is with a treatment, the more likely they are to engage in it, he said.

Del Pino said in the formative stage of the study, the researchers wanted to first observe communication dynamics among 31 pairs of siblings. According to the paper, participants discussed their experiences coming out to their siblings, attitudes toward PrEP and how they have supported each other in the past to change a behavior.

The researchers found that although the majority of the men they interviewed were aware of PrEP, only 32% were confident about accessing it, and 55% were undecided about taking the treatment.

Del Pino said other participants reported that their general practitioners, who did not specialize in infectious diseases or HIV, dissuaded them from going on PrEP. Health professionals not being up to date on PrEP acts as yet another barrier to access, he said.

Nonetheless, when the participants were asked if they would go on PrEP to alleviate their siblings’ worries about their health, over 70% said they would, del Pino said.

Six months later, out of 20 siblings who participated in focus groups, eight of them said their brothers had started using PrEP – even though the researchers had not actively promoted PrEP during the study’s initial conversations, del Pino said. He added that the trend of sibling support for PrEP continued, as 19 out of 20 siblings who participated in the focus groups said they would take PrEP if it would encourage their brothers to do so.

These results guided the researchers to develop an intervention model in which PrEP would be intentionally promoted, in contrast to the study’s initial interviewing phase, del Pino said.

The researchers also trained siblings in motivational interviewing, a method that involves open-ended questions, affirmations and summaries to encourage behavioral changes. For instance, if a sibling were to ask their brother if they would consider PrEP and the brother responds that they are fine without it, the sibling would follow up with another open-ended question, del Pino said.

“The brother might say, ‘I’m fine because I use condoms almost all the time,’” del Pino said. “Then I might say, ‘I see that you are taking positive steps towards taking care of your sexual health. Do you think you can do more?’”

Del Pino said the research group is currently working on further proving the efficacy of this intervention in a more formal scientific study.

The researchers are also looking into other family relationships, such as with cousins and mothers, and are making a control group in which subjects will have discussions about vaccines to see if there are differences from the PrEP group’s communication, he said.

“This is, in my opinion, one of the first studies to try to explore the dynamics between siblings and LMSM (Latino men who have sex with men),” Zapata said. “PrEP is this wonderful resource that so many people could benefit from.”