Prognosis and outcomes
A new UK study suggests that with prompt treatment, the life expectancy of many HIV-positive people is near normal. People who started HIV treatment when their CD4 cell count was around 350 can expect to live to the age of 75, close to the average life expectancy for the UK population as a whole.
Researchers looked at the outcomes of 17,661 UK patients who started HIV treatment between 1996 and 2008.
Overall, 7% of patients died. But the mortality rate fell considerably during the twelve years of the study.
This fall in mortality rates was accompanied by an increase in life expectancy.
The investigators calculated that a 20-year-old receiving HIV therapy in 1996-99 would live on average a further 30 years. This life expectancy increased to 46 years in the period 2006-08.
CD4 cell count at the time HIV treatment was started had a big impact on life expectancy.
For example, people who started therapy when their CD4 cell count was in the region of 200 to 350 had a life expectancy of 75 years – just a few months shorter than the average life expectancy for the general UK population.
It’s especially noteworthy that current UK guidelines recommend people should start treatment when their CD4 cell count is around 350.
However, starting treatment at a lower CD4 cell count was associated with a reduction in life expectancy of up to 18 years.
But it should be emphasised that treatment still significantly extended the life expectancy of patients, even if they started therapy with a very low CD4 cell count.
The researchers stress that it’s important to start HIV treatment promptly. They also believe that future improvements in HIV treatment and care will result in improvements in life expectancy.
HIV treatment – raltegravir
Raltegravir belongs to a class of anti-HIV drugs called integrase inhibitors. These prevent HIV from integrating with CD4 cells.
All drugs have their safety and effectiveness monitored in clinical trials.
Results from a study involving people starting treatment showed that after 48 weeks raltegravir was as effective as efavirenz (Sustiva), but caused fewer side-effects when taken in combination with other anti-HIV drugs.
Participants involved in this study have now been monitored for 192 weeks – a little under four years.
At this time point, 76% of patients assigned to raltegravir had an undetectable viral load, compared to 67% of those in another arm of the study, assigned to take efavirenz.
But this was a very strict analysis that included patients who changed treatment for any reason. A further analysis that only looked at “treatment failure” showed that 91% of patients in the raltegravir arm and 85% of individuals in the efavirenz arm maintained a viral load below 50 copies/ml.
People taking raltegravir had an average increase in their CD4 cell count of 360 cells/mm3 compared to an increase of 300 cells/mm3 for those taking efavirenz.
Drug-related side-effects occurred in 50% of people taking raltegravir compared to 80% of people in the efavirenz arm of the study.
HIV treatment – new drug
An experimental integrase inhibitor called dolutegravir appears to be very potent.
The drug is in the early stages of development, but its safety and effectiveness has been examined in two studies. These have involved people with extensive experience of HIV treatment, including people with resistance to raltegravir – currently the only licensed integrase inhibitor.
Once- and twice-daily doses of dolutegravir were examined. After 24 weeks of treatment, 75% of patients who took the drug twice a day had an undetectable viral load compared to only 41% of those treated with a once-daily dose.
A twice-daily 50mg dose of dolutegravir will now be examined in a phase III clinical trial.
Neurocognitive impairment
There’s a lot of debate about the risks of neurocognitive impairment for patients with HIV.
Some research has found that even with effective HIV treatment, rates of mild brain impairment are much higher in people with HIV compared to the general population.
However, this impairment is often so mild that it has no impact on daily life, and other studies have found that prevalence of the condition is similar in HIV-positive and HIV-negative people.
New UK research shows that it is difficult to provide a definitive answer to this question.
It involved 560 HIV-positive people enrolled in a clinical trial.
There was no clear answer about the prevalence of neurocognitive impairment. In their first set of analysis the researchers found that overall, 17% of white patients had neurocognitive impairment (measured using five neurocognitive performance tests) – similar to the 16% prevalence in the general population. But there was a 66% prevalence of impairment in black patients.
The expected scores on the tests are based on studies in the United States and Canada, so the researchers adjusted the scores to try to reflect the ethnic balance of the UK group. When the researchers adjusted their figures, the proportion of people with impairment increased or fell according to which factors were taken into account.
Researcher Alan Winston of Imperial College, London said that studies were needed matching HIV-positive and HIV-negative people according to their sexuality, race, medical history, and use of drugs.
HIV and diabetes
The research compared rates of albuminuria between three groups of patients: those with HIV and diabetes; individuals who only had HIV; and patients who only had diabetes.
The condition was present in 34% of patients with HIV and diabetes, compared to 13% of those with HIV alone, and 16% of HIV-negative diabetic controls.
When analysis was restricted to the HIV-positive patients, the researchers found that albuminuria was more common in patients taking abacavir (Ziagen, also in the combination pill Kivexa) than those taking an alternative drug (37% vs. 19%).
“We found that the prevalence of albuminuria in individuals with HIV and diabetes was two fold greater than that of individuals with either disease alone,” conclude the investigators. They call for further studies “on the persistence, progression and management of albuminuria in this unique and at-risk population.”