HIV treatment as prevention
Clinical studies have shown that HIV treatment can reduce the risk of passing on the virus to sexual partners by up to 96%.
Now researchers in KwaZulu Natal have found ‘real-world’ evidence of the impact of increased access to HIV treatment on the incidence of new infections.
Since 2004, there has been a large increase in the proportion of HIV-positive people who are taking HIV therapy in this area of South Africa. Moreover, people are accessing treatment earlier in the course of their infection.
This roll-out of treatment has been accompanied a steady fall in HIV incidence.
The researchers calculated that each 10% increase in the proportion of HIV-positive people taking treatment reduced the incidence of new HIV infections by 17%.
For more information on HIV treatment as prevention, see our factsheet, or our Preventing HIV resource.
Interactions between HIV therapy and new anti-hepatitis C drugs
Many people with HIV also have hepatitis C, often referred to as co-infection. Liver disease caused by hepatitis C is now a significant cause of illness and death in co-infected people.
Two protease inhibitors have recently been approved for the treatment of hepatitis C infection. However, there are concerns that they may interact with drugs used to treat HIV.
But new research suggests the problem may not be as serious as was feared and may be managed with dose adjustments, or by choosing HIV drugs which have less serious interactions with hepatitis C protease inhibitors. Nevertheless, more research is needed.
Investigators found that boceprevir (Victrelis) reduces blood levels of some ritonavir-boosted protease inhibitors by between 25 and 60%. The use of this drug with HIV therapy is not recommended.
However, results of another study showed that when boceprevir was combined with standard hepatitis C therapy (pegylated interferon and ribavirin), it appeared to be safe and effective for people taking HIV therapy based on a boosted protease inhibitor.
A separate study examined interactions between boceprevir and HIV therapy that included raltegravir (Isentress). The researchers found that this hepatitis C protease inhibitor had no meaningful impact on levels of raltegravir.
Other research looked at interactions between several anti-HIV drugs and an experimental hepatitis C protease inhibitor called TMC435. This drug did not have any significant impact on blood levels of the anti-HIV drugs. However, efavirenz reduced levels of TMC435 by approximately 70%.
They found that daclatasvir had no meaningful impact on levels of the anti-HIV drugs. But blood levels of daclatasvir were increased. The researchers think this could be managed by adjusting the daclatasvir dose.
Statins reduce risk of disease progression for people with HIV
Statins are used to reduce levels of LDL-cholesterol. The drugs also have an anti-inflammatory effect. Studies conducted in HIV-negative people have shown that their use reduces the risk of cardiovascular disease, even in people who do not have elevated cholesterol.
Researchers wanted to see if they had a similar benefit for people with HIV. They therefore compared rates of serious non-HIV-related illnesses and deaths between people treated with statins and those who were not taking this therapy.
Overall, taking statins reduced the risk of non-AIDS-related illness or death during the study period by 19%.
Statin use reduced the risk of cardiovascular-related illness or death by 11% and there was a 15% reduction in the risk of serious illness or death caused by other diseases. Because the study group was quite small, the statin-related reductions were not big enough to be statistically significant in relation to the overall numbers of people who experienced these health problems.
However, statins also reduced the risk of cancer by 57%.
Preventing cardiovascular disease
The development of plaque (calcium build-up) on the walls of the arteries can increase the risk of cardiovascular disease.
Researchers in the US wanted to see if therapy with metformin had any benefits.
In a randomised study, they found that HIV-positive people who took metformin had significantly less progression of coronary artery plaque than people in the control group who were not taking metformin.
The study also showed that improvements in diet and exercising more also had benefits, leading to improvements in cholesterol profile, reductions in markers of inflammation and better cardiovascular fitness.
HIV and lung disease
Doctors wanted to find out what factors were associated with lung function in patients with HIV.
They found that a viral load above 75,000 copies/ml was associated with a significant decline in lung function.
The decline in lung function associated with a high viral load was greater than that associated with cigarette smoking.
The researchers felt this showed that effective HIV treatment, which enabled people to achieve an undetectable viral load, might also slow the decline in lung function.