Doctors are now hopeful that, thanks to HIV treatment, many people with HIV will live a near-normal lifespan.
To get the most benefit from your HIV treatment, you need to take it properly.
If you don’t do this, your viral load may increase and this can lead to the development of drug-resistant strains of HIV.
HIV treatment is a lifelong commitment, so it is unsurprising that many people will experience problems taking it from time to time.
It's therefore good to know that there's a lot of help and support available. A good place to start is NAM's information booklet Adherence and Resistance.
Resistance tests
With over 20 anti-HIV drugs now available, it’s possible for virtually every patient with HIV to suppress their HIV to undetectable levels.
Resistance can mean that an anti-HIV drug doesn’t work properly. Therefore, you should have a blood test to check for resistance to anti-HIV drugs before you start, or change HIV treatment.
The results of this test will help you and your doctor decide which drugs have the best chance of working against your HIV.
The resistance tests in routine use were developed to detect resistance when viral load was 1000 copies/ml or above.
But these tests have been improved so that they can detect resistance at much lower levels.
Now UK researchers have found that these tests can correctly identify resistant virus when a person’s viral load is as low as 300 copies/ml.
Even with viral load at these low levels, the tests accurately identified strains of the virus that had resistance to each of the major classes of anti-HIV drugs.
The researchers believe that doing resistance tests for patients with low viral loads may help doctors recommend switching to a more effective treatment as soon as there's a sign of resistance developing.
Resistance common in UK patients
Researchers monitored the viral load of almost 8000 patients taking HIV treatment for up to eight years.
There have been some big advances in HIV treatment in recent years. So to make sure that the study was of relevance to the kind of treatment being used today, it only included people taking a non-nucleoside reverse transcriptase inhibitor (NNRTI), or a ritonavir-boosted protease inhibitor.
After first being suppressed, viral load increased to detectable levels in 28% of these patients.
Tests showed that resistance to certain anti-HIV drugs developed in 17% of patients.
Resistance was more likely to develop in people taking NNRTIs than in patients being treated with a protease inhibitor.
A low CD4 cell count (below 200) at the time HIV treatment was started was also found to be associated with a higher risk of resistance.