Patients should start taking drugs for the AIDS virus earlier to have the best chance of survival, researchers said Thursday.
An analysis of more than 45,000 people with HIV in Europe and North America found they were 28 percent more likely to develop full-blown AIDS or die if they deferred treatment until the point currently recommended in many countries.
There is no cure for the human immunodeficiency virus (HIV) that causes AIDS, but combinations of drugs can keep the virus from replicating and damaging the immune system.
Doctors normally don't start treatment until there is some evidence of damage to this system, measured by counting the number of immune cells called CD4 T-cells.
Current guidelines call for treatment only after the CD4 count falls below 350 cells per microlitre of blood.
Jonathan Sterne from Britain's University of Bristol and colleagues found waiting until the CD4 had fallen to 251-350 was associated with a significantly worse outcome than starting therapy in the range 351-450.
The team — whose findings were published online by the Lancet journal — concluded that a count of 350 cells should be the minimum threshold for starting treatment.
Deciding when to start taking AIDS drugs has traditionally been seen as a balancing act, since the powerful medicines can have serious side effects and there is also a risk of resistance developing.
Researchers said these problems were now easier to deal with, thanks to the advent of a wider range of drugs, and medics should therefore focus on getting patients onto therapy early.
"It is important that people at possible risk of having HIV get tested regularly so that if found to be infected they can receive the necessary care and treatment," they said.
An estimated 33 million people globally are infected with the AIDS virus, most of them living in Africa and other developing countries.
Manufacturers of AIDS drugs include GlaxoSmithKline, Pfizer , Merck, Roche and Gilead, as well as generic companies like Ranbaxy, Cipla and Aspen.
