HIV Weekly - 25th August 2010

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

HIV and heart problems

Research has shown that cardiovascular disease (CVD) - heart problems and stroke - seems to be more common in people with HIV.

Reasons suggested for this include the effects of HIV itself, side-effects of anti-HIV drugs and the fact that people with HIV also have high levels of the traditional risk factors for CVD, such as smoking and high blood pressure.

Now some research in the US has confirmed that some of these traditional risk factors are the main cause of the thickening of the carotid artery, a key early sign of CVD.

Researchers found that age, blood pressure, HDL cholesterol levels and being of African American or Hispanic origin were all associated with thickening of the artery.

There was no association between HIV disease progression and arterial thickening, nor between most classes of anti-HIV drugs and increased carotid artery thickness. In fact, one drug - tenofovir (Viread) - was found to be associated with lower arterial thickness.

Your lifestyle can have a big impact on your risk of heart disease and there’s a lot you can do to reduce the risk. It makes good sense not to smoke, to eat a healthy diet and to get some exercise.  Help is available for all these things, so ask your HIV clinic or GP.

HIV treatment

A newer anti-HIV drug, maraviroc (Celsentri), is potentially a useful treatment for people who are diagnosed late (with a CD4 count of under 200) with HIV, researchers in Austria have found.

People whose CD4 count is under 200 when they are diagnosed are at greater risk of developing a number of serious illnesses.

Maraviroc has been used for some time to treat people who have been on other sorts of anti-HIV drugs. It works by preventing HIV from interacting with CCR5 and therefore infecting other cells and replicating. It is now available as a first-line treatment and the researchers wanted to see how well it could work in people diagnosed with a low CD4 count.

Almost all types of HIV use 'co-receptors' called CXCR4 or CCR5 to allow HIV to attach to other cells. CCR5 inhibitors block infection by viruses that use CCR5. In later stages of HIV disease the virus mainly uses CXCR4, so a CCR5 inhibitor wouldn’t work against these viruses.

However, this study found that a high proportion of patients with low CD4 counts and advanced HIV disease would respond to a CCR5 inhibitor.

The study suggests that maraviroc could be a useful drug to include in a treatment combination for people diagnosed late - it shouldn’t be assumed that this drug won’t work in patients with low CD4 counts without doing a test, called a tropism test, first.

HIV, treatment and risk behaviour

Sexual risk behaviour by injecting drug users doesn’t increase once they have started HIV treatment, a study from Canada has found.

HIV treatment can both dramatically increase people’s life expectancy and reduce the chances that they will pass on the virus through sexual transmission.

But there have been some concerns that injecting drug users may have difficulty taking their treatment properly (‘adherence’), and also that people might take more risks in their sexual behaviour once they are on treatment - perhaps having more sex, more unprotected sex or a higher number of partners.

This study showed no evidence that starting HIV treatment increased any of these risk factors. The researchers recommended that different ways of encouraging and enabling injecting drug users to start HIV treatment should be put in place.

When used properly and consistently, condoms can prevent HIV and many other sexually transmitted infections.

HIV and bone health

Bone loss is an issue that affects people more as they age, and the number of older people with HIV is increasing, especially as effective HIV treatment means people are living longer.

HIV, and some HIV treatments, have also been associated with lower bone mineral density, which may possibly lead to an increased risk of fracture.

And people with HIV have high levels of other risk factors for bone loss, such as low testosterone levels, low body weight, smoking, heavy drinking and poor nutrition.

Recent research has looked at bone loss in older men, who were either HIV-positive or at high risk of becoming so because of injecting drug use or high-risk sexual behaviour.

It was found that the HIV-positive men had lower bone density then those without HIV, and that they were more likely to develop osteopenia, the precursor to osteoporosis.

Having had an AIDS diagnosis or having used heroin was also associated with greater bone loss.

There is a lot you can do to protect the health of your bones. Eating a balanced diet, with plenty of calcium and vitamin D (and taking supplements if necessary), not smoking, and taking weight-bearing exercise, will all help to reduce bone loss. Ask your clinic or GP if you’d like more information on any of these.