Cancer drugs Life expectancy of 20-year-olds starting treatment for HIV has increased by around a decade in the EU and North America since the introduction of antiretroviral therapy in the mid-1990s, according to a study published in The Lancet HIVTheir projections suggest that life expectancy of a 20-year-old who began treatment from 2008 onwards and had a low viral load after a year of treatment may approach that of the general population, which is around 78 years old.

These increases are among treated individuals, and are in addition to dramatic life expectancy improvements that occurred after the introduction of antiretroviral therapy compared with untreated individuals. The authors of the study propose that their findings could help to reduce stigmatisation and help people with HIV gain employment and obtain medical insurance, as well as encouraging those diagnosed to start treatment as soon as possible and continue it fully. However, life expectancy for people with HIV mostly remains lower than that of the general population.

"Our research illustrates a success story of how improved HIV treatments coupled with screening, prevention and treatment of health problems associated with HIV infection can extend the lifespan of people diagnosed with HIV. However, further efforts are needed if life expectancy is to match that of the general population," said lead author Adam Trickey, from the School of Social and Community Medicine at the University of Bristol. "Combination antiretroviral therapy has been used to treat HIV for 20 years, but newer drugs have fewer side effects, involve taking fewer pills, better prevent replication of the virus and are more difficult for the virus to become resistant to."

The improvements are likely to be a result of the transition to less toxic antiretroviral therapy with more drug options for people infected with a drug-resistant HIV strain, better adherence to treatment, improved treatment of co-occurring conditions and opportunistic infections, and increased use of screening and prevention programmes for conditions such as cardiovascular disease and cancer.

Antiretroviral therapy first became widely used in 1996. It involves a combination of three or more drugs that block the HIV virus from replicating, in order to prevent and repair damage to the immune system caused by HIV infection. It also prevents onward spread of the disease. The WHO now recommends antiretroviral therapy to be given as soon as possible after diagnosis to all people with HIV.

The study used data for 88,504 people with HIV who started antiretroviral treatment between 1996 and 2010 from 18 European and North American studies. In order to estimate life expectancy, it tracked how many people died during the first three years of their treatment, their cause of death, HIV viral load, immune cell (CD4 cell) count and whether they were infected through injecting drugs.

Fewer people who started treatment between 2008-2010 died during their first three years of treatment than those who started treatment between 1996-2007. When looking specifically at deaths due to AIDS, the number of deaths during treatment declined over time between 1996 and 2010, likely as a result of newer drugs being more effective in restoring the immune system.

During this time, measures of HIV improved – with the average immune cell count (of CD4 cells in the blood) after a year of treatment increasing from 370 cells per microlitre of blood in 1996-1999, to 430 cells per microlitre in 2008-2010, while the proportion of people with a low HIV viral load increased from 71 per cent to 93%.

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