IT’S NEARLY 30 years since the link was made between HIV and Aids, and by 2009, about 33 million people were thought to be living with the virus worldwide.

Today, people infected with HIV who have access to drug therapy can live relatively long lives, but patients with chronic HIV infection are at higher risk of heart disease and bone problems, according to a major study in Dublin, which has highlighted the need for early diagnosis and treatment.

“We are now in an era where we have very effective treatment for HIV,” says Prof Bill Powderly, who heads the Dublin HIV Cohort Study which has been tracking patients since 2006. “It means people are living longer, they are getting older with a chronic condition and emerging medical issues are coming up.”

The study, funded by the Health Research Board, enrolled more than 1,700 patients with HIV in Dublin and has been looking at the types and spread of the virus in the city, as well as the medical impacts.

“The idea we had was to gather data on the HIV-infected population in Dublin and then follow them over a period of time to look at the evolution of the infection in the modern era,” says Powderly, professor of medicine at University College Dublin, who worked on the project with Prof Colm Bergin and Prof Fiona Mulcahy at St James’s Hospital, and others.

Their analysis showed that about a quarter of transmission of the virus was through male-to-male sexual contact, and a similar percentage was through intravenous drug use, or needle sharing. About half of transmission was through heterosexual contact, where in most cases the virus was acquired outside Ireland.

By linking with the National Virus Reference Laboratory, the cohort study could pinpoint which types of HIV are circulating in Dublin.

“We were able to see patterns of infection in Ireland and if were there any emerging issues around resistance to drugs,” says Powderly, who describes how they identified mainly the “classic northern European style of virus” and subtype C HIV.

Meanwhile, the news on drug resistance from the study is welcome, according to Powderly. “The good news is that we are very like other parts in western Europe. We haven’t seen a rise in resistance, which is very reassuring because if we get resistance to the drugs, then we have a much greater problem,” he says. “We are also fortunate that we haven’t seen any patient who has multiple resistance against many drugs – but this is a potential problem and we have to be aware of it.”

So what happens when patients can keep the infection under control using drug therapies? The Dublin study has been looking at the impact on heart attack and osteoporosis risks.

“It turns out that people with chronic HIV infection have a greater risk of heart disease than the general population,” says Powderly. “Part of that is [from] some of the drugs themselves – one of the side effects is to increase cholesterol in the blood. Other research shows that HIV itself as an infection may be accelerating atherosclerosis , so it’s another reason for getting aggressive about treating the virus.”

Many patients on the study underwent bone scans, and the findings point to a jump in their risk for thinning.

“We have shown the frequency of osteoporosis and osteopenia, which is less severe bone thinning, is about twice what you would expect for that age match,” says Powderly, who describes a possible dual effect of how the virus itself may have an impact on bone metabolism, while the drug treatments could affect bone turnover in the body.

“As people live longer, that becomes a more important issue because there’s a greater risk of fracture,” he explains.

“The real question that can only be answered by long-term studies is whether it is going to be an issue in people who are surviving with HIV into their 50s and 60s, and we would hope to be able to contribute to those studies. Also, by describing it and exploring what the mechanisms are we may be able to come up with a preventive strategy.”

A key to helping patients is early diagnosis and treatment. “Now that we have data to suggest that active HIV infection is a significant contributor to some of these problems, it raises the bar in saying you need to treat the HIV infection – it’s an important lesson that’s coming out of research across the world, earlier treatment is associated with better outcomes,” he says.

STEPS TO TAKE IF EXPOSED TO HIV

If you think you have been exposed to HIV, you should contact your GP, student health support or local STI service to get tested, according to Dr Fiona Lyons, a consultant genitourinary physician at the specialist STI unit, The Guide Clinic, in St James’s Hospital in Dublin.

If you think exposure to the virus happened in the past 72 hours, a short-term antiretroviral treatment could reduce the likelihood of HIV infection, but the drugs need to be started within 72 hours of possible exposure to HIV, and the sooner the better, according to the clinic’s website.

Lyons encourages people to get tested, which involves giving a blood sample. If the result comes back as positive for HIV, services can offer packages of care and support.

For more information about HIV and testing, see guideclinic.ie or yoursexualhealth.ie. To contact the HIV/Drugs Helpline, freefone 1800-459459 or e-mail drugshiv@hse.ie

The Guide Clinic is hosting a fundraising Christmas concert in Christ Church Cathedral, Dublin, at 8pm on Thursday, – World Aids Day. Tickets €20. See guideclinic.ie

Thursday is World Aids Day