Treatment as prevention success in Denmark

A new study from Denmark provides some of the clearest evidence yet that ‘treatment as prevention’ can really make a big difference at the population level. There’s already very good evidence that individuals living with HIV can avoid transmitting the virus by taking HIV treatment.

But there are questions about whether HIV treatment can really stop HIV transmission across a population. For example, in the United Kingdom, too many people have HIV without realising it, so HIV continues to be spread, even though most people with diagnosed HIV are receiving HIV treatment.

But in Denmark, people get tested for HIV more often and so individuals tend to be diagnosed quite quickly, with a high CD4 count. Denmark has an efficient system of universal, free healthcare and the uptake of HIV treatment is very high.

The researchers estimate that the rate of new HIV infections in gay men (the main group affected by HIV in the country) is 0.14% per year. In other words, one in 700 gay men acquire HIV each year.

In contrast, incidence in gay men in the UK is four times higher at around 0.6% per year.

The study shows that treatment as prevention can work but that very high rates of early diagnosis, treatment uptake and viral suppression are required.

High blood pressure

Dutch researchers have found that high blood pressure (hypertension) is extremely common in middle-aged and older people living with HIV. People who were overweight, who smoked or who drank alcohol were more likely to have high blood pressure. But the study also showed that people who had previously used the old anti-HIV drug stavudine (d4T, Zerit) had more problems with high blood pressure.

If blood pressure is high, it causes a strain on blood vessels and the heart. The higher the blood pressure is, the greater the risk of stroke, heart problems and kidney failure.

The researchers recruited just over 500 people living with HIV over the age of 45, comparing them with a closely matched group of HIV-negative people. Reflecting the HIV epidemic in the Netherlands, the vast majority of participants were gay men.

While 36% of the HIV-negative participants had high blood pressure, this rose to 48% of HIV-positive participants. Even after making statistical adjustment for age, gender, smoking, alcohol, exercise and weight, people living with HIV were more likely to have high blood pressure.

The researchers found that part of the explanation for increased rates of high blood pressure in this group of older HIV-positive people were changes in body composition associated with lipodystrophy, including excess stomach fat and loss of fat. While the people in this study were mostly doing well on modern anti-HIV drugs, many had been taking HIV treatment for decades. Over a third had previously taken stavudine (d4T, Zerit), a drug that we now know is associated with lipodystrophy. These individuals were more likely to have high blood pressure. 

There’s more information in NAM’s factsheet on high blood pressure.

Hepatitis C treatment

Does having HIV affect people's response to hepatitis C treatment?

We know that, without treatment, people who have HIV co-infection tend to have more liver damage and get sicker more quickly than people who have hepatitis C only. And people with HIV co-infection do not always have such good results with the older hepatitis C treatments (pegylated interferon injections + ribavirin tablets).

Concerning the newer hepatitis C drugs, results from clinical trials have shown identical results for people with HIV co-infection. 

Now, two different studies of the "real-world effectiveness" of these drugs have produced conflicting findings. In both, the results for several hundred people with HIV/hepatitis C co-infection were compared with those of people with hepatitis C mono-infection only. In both, most people had genotype 1 and around half had cirrhosis.  

An American study found that around 90% of people with co-infection had a sustained virological response 12 weeks after finishing treatment – identical results to people who had mono-infection. 

But a Spanish study found slightly poorer results for people with co-infection, with around 5% or 10% fewer people achieving a sustained virological response. This could be because those with HIV were sicker when beginning the treatment, because some did not adhere to treatment as well, or because of damage to the immune system in people with HIV. 

The conflicting results of the two studies show that the relationship between HIV and hepatitis C is still not fully understood. 

There’s more information in NAM’s booklet 'HIV & hepatitis’.