25 April 2008

HIV+, lab monitoring no help

Patients with HIV who aren't monitored with the expensive laboratory tests commonly used in rich countries may survive just as long as those who do get the tests, a new study says.

Patients with HIV who aren't monitored with the expensive laboratory tests commonly used in rich countries may survive just as long as those who do get the tests, a new study says.

In a paper published in The Lancet medical journal, experts found only a slight difference between the survival rates of HIV patients on antiretrovirals who were monitored with laboratory tests and those who weren't. Lab tests can be an early indication of problems in HIV patients that aren't yet obvious.

The research was based on computer modelling and while the results must be verified, they could influence how HIV patients across Africa and Asia are treated.

As drugs to combat Aids have been distributed across developing countries, some doctors worry that without lab monitoring, patients will either die earlier or develop drug resistance faster. But based on the evidence to date, that has not happened.

'We shouldn't wait'
"We often get stuck in letting the perfect be the enemy of the good," said Jennifer Kates, an HIV expert at the Kaiser Family Foundation in Washington. She was not connected to the study.

"Waiting for the perfect lab infrastructure to be ready before rolling out antiretroviral therapy means that millions of people will die," Kates said. "This study says we shouldn't wait."

Andrew Phillips and colleagues from the Royal Free and University College Medical School in London used a computer model that simulated patient details based on HIV progression in real patients.

How the study was done
They then projected the patients' survival for up to 20 years. Data from real patients are not yet available.

Phillips and his colleagues essentially found that 83 percent of patients who were monitored with lab tests survived five years, compared with 82 percent for those who went without the tests.

Over two decades, 67 percent of those who got lab tests survived versus 64 percent for those who didn't. The difference is negligible - and contradicts long-held beliefs that antiretrovirals must be accompanied by regular laboratory monitoring to benefit patients.

Only half of those the estimated 33 million people with Aids globally are receiving the drugs, experts said. "Laboratory monitoring shouldn't be the priority while we've got less than half of people who need treatment still waiting for it," Phillips said.

HIV patients in West regularly tested
Phillips developed the original computer model with funding from Pfizer Inc., makers of many antiretrovirals, the drugs used to fight HIV and Aids.

In the west, people with HIV undergo routine lab tests about every six months to check the amount of virus in their body and the status of their immune systems. If a patient has too much virus or their immune system is weak, doctors usually switch drugs.

But in poor countries, most patients are simply monitored by a doctor or nurse. Only a few countries in Africa run regular lab tests, and results often take too long to benefit patients.

Consequently, patients are only switched to other drugs if they start developing bacterial infections, skin diseases or other suggestions of an Aids complication.

"It's counterintuitive that people who do not get laboratory monitoring seem to do just as well as those who do," said Charlie Gilks, an Aids treatment expert at WHO and one of the paper's authors.

Not all experts convinced
Some experts worry that because people who are not monitored with lab tests stay longer on drugs that don't work, they could be spreading drug-resistant HIV. Nathan Ford, head of Medecins Sans Frontieres' medical unit in South Africa, said there are no signs that drug resistance is developing more quickly in Africa than elsewhere. Ford was not involved in the study.

He and others said developing countries should still work on making lab services a standard part of HIV care.

"We shouldn't accept that this is too complicated and expensive and we need to do without it," Ford said.

"In an ideal world, you would want lab support everywhere," said Aids expert Gilks. "But right now we need to continue to roll out the medicines because that is what's going to save lives." – (Sapa)

April 2008

Read more:
HIV hiding in cells from ARV's
Patch helps brain pain in HIV+


Read Health24’s Comments Policy

Comment on this story
Comments have been closed for this article.