Research presented at the Tenth Congress on Drug Therapy in HIV Infection in Glasgow earlier this month shows that HIV infection still significantly impairs life expectancy amongst patients in the UK.
HIV still cuts 13 years off the average person’s life expectancy, the conference heard, although ten of those years are due to people coming forward for testing late, with CD4 counts under 200 cells/mm3.
The impact of the virus is disproportionately suffered by men, whose loss of life expectancy due to HIV is twice that of women.
However, a great many of the excess deaths due to HIV observed in the cohort studies were a result of late diagnosis: people diagnosed with low CD4 counts who died in the first year after presenting for an HIV test. The life expectancy deficit for people who maintained a CD4 count over 200 was 6.5 years post-2000 and in the last two years has become near-normal, presenter Margaret May said.
UK CHIC is a cohort study which combines observations from 30 different HIV clinics in the UK. The study examined nearly 18,000 patients who started antiretroviral (ARV) treatment between 1996 and 2008. It excluded people who started ARVs with a CD4 count of over 350 cells/mm3, and it also excluded injecting drug users, thus excluding the groups that were likely to have the highest and lowest life expectancies.
Three-quarters of the group were male and 58% gay men, and 60% white. The median age at which people started ARV treatment was 37 and their average CD4 count at this point was 166.
Seven per cent of the patients (1248 people) died and the death rates for patients diagnosed during four three-year periods (1996-99, 2000-02, 2003-05 and 2006-08) were calculated. These were then used to compute a standardised mortality in the form of life expectancy at age 20: the additional extra years of life that a person could expect to live when they reached their 20th birthday. (This does not mean life expectancy if they were all diagnosed at age 20. It means life expectancy at age 20 of someone who was or subsequently became HIV positive; in other words it demonstrates the impact of HIV infection on an individual’s lifespan, regardless of age at diagnosis.)
During the earliest period (1996-99) life expectancy was 30 years; in other words, a person diagnosed with HIV during these years could expect, at the age of 20, to live until they were 50. (Note that if you were diagnosed during these years and are now in your late 40s, it does not mean you only have a few years left: life expectancy increases as people get older, because the fact that you have survived in itself makes it more likely that you will continue to live.)
By 2006-08 this had improved by one-third to 46 years; in other words, they could expect to live until 66.
However, this is still 13 years lower than the average life expectancy at age 20 in the general UK population. Furthermore, there was considerably disparity between men and women. In the general population the life expectancy difference between men and women has narrowed, with improvements in early death due to heart disease in men, to only two years; a 20 year old man can expect to live till 80 and a woman till 82.
But in the population of HIV-positive people as a whole, men have a life expectancy at age 20 of 40 years (implying that a man diagnosed with HIV can expect to live until the age of 60) and women of 50 years: exactly why this is the case will take more research.
Life expectancies continue to improve, however. For people diagnosed with HIV during 2006-08 who have maintained a CD4 count of over 200, life expectancy at age 20 is now equal to that in the general population.
Margaret May said that if everyone got diagnosed with a CD4 count of over 200, this would improve life expectancies by ten years.
“In conclusion,” she said, “we join the advocacy for improved diagnosis and timely treatment, which could improve the life expectancy of people with HIV in the UK.”
May M et al. Impact on life expectancy of late diagnosis and treatment of HIV-1 infected individuals: UK CHIC. Tenth International Congress on Drug Therapy in HIV Infection, Glasgow. Abstract O233. 2010.