Tenofovir and kidney health

Treatment with the anti-HIV drug tenofovir has an impact on kidney function, new research shows.

However, this is rarely serious enough to cause illness.

Tenofovir (Viread, also in the combination pills Truvada and Atripla) is a very widely used anti-HIV drug.

It is considered a very safe drug, but there have been case reports of it causing kidney problems.

Researchers wanted to find out how many patients were experiencing kidney side-effects caused by tenofovir and how serious these were. They therefore looked at the results of 17 studies involving 11,000 patients. All the studies compared HIV treatment combinations containing tenofovir to combinations that included an alternative drug.

Results showed that there was a greater loss of kidney function amongst patients treated with tenofovir than in patients taking an alternative drug.

Patients taking tenofovir were also more likely to develop kidney disease in the short term. But treatment with tenofovir was not associated with any increase in the risk of chronic kidney disease, or of end-stage kidney failure requiring long-term dialysis. Nor were patients taking tenofovir more likely to have protein in their urine.

Tenofovir has also been linked in some research to loss of bone mineral density. But there was no evidence of this in the 17 studies that the researchers analysed.

In the UK, kidney function and bone health is monitored as part of routine HIV care. It’s therefore possible to spot any potential problems early and offer appropriate treatment.

Stopping prophylaxis for PCP

Patients who are taking HIV treatment and who have an undetectable viral load can safely stop PCP prophylaxis when their CD4 cell count is as low as 101.

PCP (also known as Pneumocystis jiroveci pneumonia) is an AIDS-defining illness.

The risk of this infection is greatest when a patient’s CD4 cell count is below 200.

All patients whose CD4 cell count is below this level are recommended to take HIV treatment. They are also recommended to take an antibiotic called cotrimoxazole (also known as trimethoprim-sulfamethoxazole, or Septrin) to stop them developing PCP. This kind of treatment is called PCP prophylaxis and current guidelines recommend that patients should take this treatment until their CD4 cell count increases to above 200.

But researchers have found that PCP was extremely rare in European patients taking HIV treatment whose CD4 cell count was above 101 and whose viral load was undetectable.

They therefore believe that guidelines on the use of PCP prophylaxis in Europe should be revised.

However, these results shouldn’t be applied to resource-limited settings. Here prophylaxis with cotrimoxazole has a number of benefits. For example, it has been shown to reduce the risk of bacterial infections and malaria.

The ageing HIV epidemic

There has been a big increase in the number of HIV-positive patients aged over 50 in England, Wales and Northern Ireland. The over-50s now account for 16% of all those receiving HIV care.

Between 2000 and 2007, the over-50s constituted 8% of all new HIV diagnoses in the countries.

Almost half of all older patients were diagnosed late, and diagnosis with a CD4 cell count below 200 significantly increased the risk of death.

Some of the issues that older HIV-positive patients have to face include:

• Stigma related to both HIV and older age.

• The diseases of ageing, such as cardiovascular disease. HIV can increase the risk of such illnesses.

• Lack of targeted prevention resources.

If you would like more information following an HIV diagnosis, or to know more about HIV and ageing, there is plenty of help available. There are lots of organisations offering support to people living with HIV. THT Direct (0845 122 1200 or info@tht.org.uk) can provide information on HIV and is staffed by trained advisers who can help you talk through some of your feelings and help to put you in touch with local support.