Outcomes improving for HIV patients in the UK
They also established that the proportion of patients with a dangerously low CD4 cell count was halved in this period.
A model projecting outcomes until 2012 predicted that they would continue to improve.
The number of deaths amongst people with HIV in the UK fell dramatically after the introduction of effective HIV treatment in the late 1990s.
Researchers wanted to see if this drop in mortality was being sustained, and what proportion of patients had a CD4 cell count above 200 and an undetectable viral load.
They found that increasing numbers of patients had experience of HIV treatment. This translated into a fall in the proportion of patients with a CD4 cell count below 200 from 19% in 2000 to 8% in 2007.
The annual number of deaths remained stable throughout this period, and no increase was projected through to 2012. But as the number of people living with HIV in the UK has increased substantially, this stable mortality rate meant that there was a fall in real terms.
HIV treatment has improved significantly in recent years. The drugs available now are more powerful, cause fewer side-effects and are easier to take than those used ten years ago.
The benefits of these improvements in HIV treatment were suggested by a substantial increase in the proportion of patients taking therapy who had an undetectable viral load – from 62% in 2000 to 83% in 2007.
The number of patients with resistance to the three original classes of anti-HIV drugs (NRTIs, NNRTIs and protease inhibitors) was projected to increase. But the development of anti-HIV drugs that work against resistant virus meant that most of these individuals were able to achieve an undetectable viral load.
When to start treatment
A new study has added information to the debate on the best time to start taking HIV treatment.
Current UK guidance (which will be updated later this year) recommends starting treatment when your CD4 cell count is around 350. Starting treatment at this time, compared to waiting until your CD4 count is lower, reduces the risk of HIV-related illnesses and some other serious diseases.
But some doctors think that there would be advantages to starting treatment sooner. This is partly because of evidence that even low viral loads cause inflammation, and that this can increase the risk of illnesses such as cardiovascular disease.
To explore whether HIV-positive people who have CD4 counts above 350 and are not on treatment are still more at risk of dying than people who do not have HIV, researchers looked at mortality rates in 40,000 patients who were diagnosed soon after their infection with HIV.
The researchers found that death rates amongst patients with HIV were still higher than those seen in the general population. But this varied according to risk group – the mortality rate was only slightly increased amongst gay men. The researchers therefore believe that lifestyle and socioeconomic factors are contributing to the higher mortality rates seen in HIV-positive injecting drug users and heterosexuals.
The researchers also found clear evidence that people with a CD4 cell count above 500 had a lower twelve-month mortality rate than people with a CD4 count between 350 and 499. This provides further support for trials looking into the benefits of starting treatment earlier than currently recommended.
Predicting outcomes for patients
Researchers from an international study have shown that measuring total lymphocyte count and haemoglobin levels (anaemia) can help predict the prognosis of patients starting treatment.
The study looked at two models used to predict the likelihood of death in the first year of treatment for patients in Africa. But one model relied on CD4 cell counts and these are often not available in poorer settings.
The second model replaced CD4 counts with measurements of total lymphocyte count and anaemia.
Both models were equally accurate at predicting the mortality risk of patients during their first year of antiretroviral treatment.
Researchers suggest that lymphocyte and haemoglobin levels are a reliable way of predicting which patients will benefit from treatment.
HIV and the criminal law
In many countries people with HIV have been prosecuted because they didn’t tell their sexual partner they had the virus.
In England, a person with HIV can only be prosecuted if they don’t disclose their HIV status to their sexual partner and transmission occurs. However, in some countries you can be charged for just having sex without disclosing your HIV status, even if there is no transmission.
For example, in the Netherlands constitutional arguments were used to stop prosecutions.
In England, the defence was able to show the limitations of the scientific evidence that the prosecution was relying on to secure convictions.
In Switzerland, the Geneva Court of Justice ruled that a person was not guilty of unlawfully exposing a sexual partner to HIV because the accused had an undetectable viral load and was fully adherent to treatment. In these circumstances, the objective risk of transmission was judged to be so low that it was hypothetical. In this decision, the court was aided by the Swiss Federal AIDS Commission’s statement on transmission risks and by expert testimony from one of its authors. This tactic is relevant in exposure (rather than transmission) cases.
NAM has recently published a new resource HIV and the criminal law. It is currently available in full online and a print version is in production.
A satellite meeting, 'Criminalisation of HIV exposure and transmission: global extent, impact and the way forward', was held in Vienna and you can view a video of the meeting on our website.