HIV Weekly - 3rd February 2010

There’s a lot of debate about the best time to start HIV treatment.

Taking HIV treatment reduces the risk of becoming ill with HIV. Treatment with anti-HIV drugs also means that the risk of developing other serious illnesses – for example heart, kidney, or liver disease – is reduced.

Research summarised in this edition of HIV Weekly shows that these diseases can be related, and that HIV-positive patients with kidney problems are more likely to develop cardiovascular disease. 

In addition, separate research showed that HIV-positive patients co-infected with hepatitis C were more likely to develop kidney problems.

It’s currently recommended that you should start HIV treatment when your CD4 cell count is around 350 cells/mm³. Treatment at this time is especially recommended if you have heart, kidney, or liver disease (or a risk of them), or are co-infected with hepatitis B or C.

ddI and liver disease

A rare, but serious, liver problem is now thought to be a possible side-effect of the nucleoside reverse transcriptase inhibitor (NRTI) ddI (didanosine, Videx).

In the US, non-cirrhotic portal hypertension is now listed as a potential side-effect of the drug.

This can be a very serious condition and involves the build-up of pressure in the portal vein in the liver. This can lead to serious bleeding and even death.

Swiss research showed that the sole risk factor for non-cirrhotic portal hypertension in patients with HIV was treatment with ddI.

The drug can also cause other long-term side-effects and this is one of the reasons why it isn’t used very much.

But it remains an important option for some patients. Authorities in the US are recommending that doctors and patients decide if the benefits of taking ddI outweigh any possible risks.

For more information on side-effects you may find the NAM Side-effects booklet helpful. It is available free to people with HIV , as well as on our website and through clinics and organisations in the UK.

Kidney disease

People with HIV have an increased risk of kidney disease.

A number of factors contribute to this. HIV itself can damage the kidneys, as can hepatitis C virus. In addition, kidney problems may be a side-effect of some anti-HIV drugs.

Now US researchers have found that kidney dysfunction is associated with an increased risk of cardiovascular disease in patients with HIV.

The researchers compared a key measure of kidney function (estimated glomerular filtration rate, or GFR) between 63 HIV-positive patients who had had a heart attack or stroke and 252 HIV-positive patients without cardiovascular disease.

They found that poorer kidney function was associated with an increased risk of cardiovascular disease.

Separate research has shown that HIV-positive patients who are co-infected with hepatitis C have an increased risk of kidney problems.

The research also showed that poorer kidney function increased the risk of death.

Abacavir and heart disease

Danish researchers have found further evidence that treatment with the NRTI abacavir (Ziagen, also in the combination pills Kivexa  and Trizivir ) increases the risk of heart attack.

The large D:A:D side-effects study and the SMART treatment interruption study showed that taking abacavir increased the risk of heart attack.

The Danish research showed that taking abacavir doubled the relative risk (i.e. compared to people not taking the drug) of heart attack. 

The risk, reduced after treatment with abacavir was stopped, was still higher than before this treatment started.

The association between treatment with abacavir and heart attack was still present even after the researchers took into account both traditional and HIV-related risk factors for heart attack.

It’s important to put this risk into some perspective.

Smoking and other traditional risk factors for heart disease, such as high cholesterol, diabetes and a family history of heart problems, are associated with much bigger increases in the risk of heart disease than taking abacavir.

So too is leaving HIV untreated.

Indeed, the study looking at the relationship between kidney function and heart disease noted above found that both a CD4 cell count below 200 and diabetes increased the risk of cardiovascular disease.

Nevertheless, current British HIV treatment guidelines say that abacavir should be avoided by people with other risk factors for heart disease.

The next edition of HIV Treatment Update will include features on giving up smoking and on taking up exercise, as well as an interview with Prof. Brian Gazzard and Prof. Jens Lundgren on the British and European treatment guidelines.

Visit our online bookshop to subscribe or contact us for more information at   info@nam.org.uk  or on 020 7837 6988.  HIV Treatment Update is available free to people living with HIV .

Contraception and metabolic problems

Progestogen-only contraception is the type of hormonal contraception preferred for women with risk factors for cardiovascular disease such as high blood pressure and smoking. It’s also used by women who suffer from migraines. And it's the type of contraception often given to women with HIV because it does not interact with anti-HIV drugs.

However, this type of contraception has now been found to be associated with cholesterol increases and other metabolic problems in women with HIV.

US researchers have found use of this type of contraception by women with HIV is associated with lower levels of ‘good’, HDL cholesterol, and increased levels of ‘bad’ LDL cholesterol. It also increased the risk of insulin resistance which can lead to diabetes.