Risk for heart disease in young adults with HIV – HIV update, 9 May 2024

A round-up of the latest HIV news, for people living with HIV in the UK and beyond.

9 May 2024

Risk for heart disease in young adults with HIV

We already know that people with HIV are at higher risk of coronary heart disease than the general population. Taking effective HIV treatment is an important way of keeping your risk of heart disease as low as possible but it doesn’t reduce it to the same level as someone without HIV.

A study in the US has now found that young people who’ve had HIV since birth have a high prevalence of metabolic conditions, like diabetes and raised cholesterol. Usually these conditions are most common in middle-aged or older people. They affect how our body produces energy – having any metabolic condition increases your risk for heart disease, like a heart attack or stroke.

The researchers looked at 375 young people aged 18 to 30 who’ve had HIV since birth. They found that by the age of 30, 19% had developed diabetes, 40% had elevated cholesterol, 50% had elevated triglycerides (a type of blood fat), 22% had high blood pressure and 25% had chronic kidney disease.

Type 2 diabetes was between three and six times higher than in young adults without HIV and in older people with HIV. The incidence of high blood pressure was 50% higher than in young adults without HIV. The prevalence of chronic kidney disease in young people with HIV was four times higher than in older people with HIV.

The researchers haven’t yet seen higher rates of cardiovascular events (like heart attacks and strokes) in young people who’ve had HIV since birth. However, the high rates of metabolic conditions are warning signs that they are at higher risk for these cardiovascular events.

Experts are now discussing how HIV doctors should monitor and respond to these warning signs. In addition to measuring cholesterol and triglyceride levels in the blood, doctors may also look at the thickness of the inner two layers of the carotid arteries or use MRI scans to detect fibrosis (scarring) of the heart. This can help detect warning signs even if you don’t have any symptoms.

A recent study also showed that preventive treatment with medications known as statins reduced cardiovascular events in people with HIV. However, only people over the age of 40 took part in the study. That means current guidelines don’t yet recommend preventive statins for people with HIV under the age of 40. More research is needed to see if statins are useful for younger people with HIV.

If you’re worried about metabolic conditions or your risk for heart disease, or you want advice on how to best manage these conditions, we recommend you speak to a member of your health care team.

PrEP for women

Pre-exposure prophylaxis (PrEP) is a form of HIV prevention that uses anti-HIV drugs to protect HIV-negative people from acquiring HIV. PrEP can either be taken as a daily pill or as event-based dosing. Event-based dosing means taking pills before and after having sex. Event-based dosing is not yet recommended for those at risk of acquiring HIV through vaginal sex.

We already know that taking four out of seven PrEP pills per week was enough to provide protection for men who have sex with men. However, we didn’t know if taking only four out of seven doses is also enough to provide protection for women. That’s because the belief was that women needed near perfect adherence (taking a daily dose exactly as prescribed) to make sure the drug levels in the vagina would be high enough to provide protection.

Now a new research paper has analysed 11 studies of PrEP that included women. The results show that taking four to six pills a week was almost as effective at preventing HIV infection as taking the pills every day.

In total, the 11 studies included 6296 cisgender women. The researchers assigned each participant into one of four groups depending on how consistently they took their PrEP medication:

Consistent daily or near-daily adherence (close to 7 pills a week)
Consistently high adherence (meaning 4 to 6 pills a week)
Consistently low adherence (0 to 2 pills a week)
Adherence started off relatively high but then declined.

Among the 6296 participants in the 11 studies, 32 acquired HIV. On average, 0.72% acquired HIV each year. But many more women under the age of 25 acquired HIV (1.33%) than women over the age of 25 (0.24%). This is probably because older women took PrEP more consistently.

There were no new HIV diagnoses in the 498 women who took PrEP daily or near-daily. There was only one HIV diagnosis in 658 women in the 4-6 pills a week group. This equates to an incidence rate per 100 person-years of 0.13. It means 0.13 people out of 100 people in this group would get a new HIV diagnosis each year. Incidence in the high-but-declining group was 0.49, and in the women who took little or no PrEP, it was 1.27.

This evidence shows us that four or more doses of PrEP a week offer high protection – a very reassuring number. It shows that women don’t need perfect adherence to PrEP (taking it every single day) for it to work. And it shows that event-based PrEP may also be an option for women, but we need more research to confirm this.

Weight loss when switching from TAF to TDF

Tenofovir disoproxil (TDF) is a drug commonly found in older HIV medications, including Truvada, Atripla, Stribild, Eviplera and Delstrigo. The use of TDF, however, is associated with a slightly increased risk of kidney and bone issues. Due to these effects, a newer formulation of TDF has been created with the name of tenofovir alafenamide (TAF). TAF is found in commonly used HIV medications such as Descovy, Biktarvy, Symtuza and Odefsey.

However, people taking TAF appear to gain more weight than people taking TDF. This is important to take into consideration, as weight gain associated with HIV treatment may increase the risks of diabetes and cardiovascular disease. To better understand whether switching from TAF to TDF could help with weight loss, researchers studied the changes in metabolism and body weight in people enrolled in the Swiss HIV Cohort.

In this cohort, 6555 people were initially on a TAF-containing regimen. While 83% remained on this medication between 2016 and 2023, 16% switched to another medication during that time. Some of these people swapped TAF for TDF and had modest reductions in body weight, cholesterol, and triglyceride levels. On the other hand, weight remained stable in people who switched to other drug regimens that did not contain TDF.

Overall, it is worth considering the pros and cons of taking TAF- vs TDF-containing medications. TDF can reduce body weight, but it is also important to consider whether this benefit outweighs the potential benefits of TAF in terms of improved kidney and bone health.

Hidden hepatitis B and two-drug treatment

Hepatitis B is an infection that can cause severe liver damage if it’s not treated. Hepatitis B is most common in Africa, the Indian sub-continent and throughout the rest of Asia. Around 7% of people with HIV in the UK also have hepatitis B. This is known as co-infection.

A common two-drug treatment regimen is dolutegravir / lamivudine (Dovato). It doesn’t include tenofovir, which is a component of many other HIV regimens and is also active against hepatitis B. Because of this, switching from a regimen that contains tenofovir to a regimen that doesn’t (like dolutegravir / lamivudine) is not recommended for people who have an active hepatitis B infection. However, a study has now found that people with HIV who have a hidden infection with hepatitis B (also called occult infection) may also have reduced viral suppression after a switch to dolutegravir / lamivudine.

Having a hidden hepatitis B infection means that hepatitis B DNA and hepatitis B core antibodies (a sign of past hepatitis B infection) can be detected in your liver tissue or blood. But in contrast to an active hepatitis B infection, no hepatitis B surface antigen or surface antibodies can be found when you have a hidden infection. These are two markers we would expect to see in an active infection.

The researchers looked at 267 people with HIV in Italian and French clinics who had switched from three-drug treatment to dolutegravir / lamivudine. All participants had a viral load below 50 at the time of switching.

Before switching to dolutegravir / lamivudine treatment, there was no difference in viral suppression (having very little HIV in the body) between people who had signs of a hidden hepatitis B infection and those who did not. But 12 months after switching, fewer of those with signs of a hidden infection had viral load below 20 copies with a result of “target not detected” (which means there was no detectable virus whatsoever). They were more likely to have viral loads between 20 and 50 copies. People with signs of a hidden hepatitis B were also three times more likely to have detectable HIV 36 months after switching treatments.

The results show that people who switch from three-drug treatment to dolutegravir / lamivudine may be at higher risk of increased viral load if they have a hidden hepatitis B infection. That why it’s important that doctors monitor levels of hepatitis B activity and HIV in your blood if test results show that you may have a hidden hepatitis B infection. This is in alignment with current European guidelines that say that people with signs of hidden hepatitis B infection should be monitored after switching to dolutegravir / lamivudine. The guidelines do not advise against the use of the combination if you have hidden hepatitis B – as long as your doctor carefully monitors your blood levels.

If you’re concerned about having hepatitis B infection or worried about switching treatments, we recommend you speak to member of your healthcare team.

Risk for heart disease in young adults with HIV – HIV update, 9 May 2024