WASHINGTON — People who have the AIDS virus should start drug treatments sooner than current guidelines recommend, suggests a large new study that could change the care of hundreds of thousands of Americans.
The study found that delaying treatment until a patient's immune system is badly damaged nearly doubles the risk of death in the next few years compared with patients whose treatment started earlier.
Doctors have thought it would be better to spare patients the side effects of AIDS drugs as long as possible.
"The data are rather compelling that the risk of death appears to be higher if you wait than if you treat," said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, which helped pay for the study.
If the results prompt doctors to change practice — as Fauci and other AIDS specialists predict — several hundred thousand Americans who are not taking AIDS drugs now would be advised to start.
The study was reported Sunday at an infectious diseases conference in Washington.
About 56,300 Americans are newly infected with HIV each year. The virus ravages T-cells — "helper cells" of the immune system that fight off germs. Once that happens, people can fall prey to a host of diseases that prove fatal.
Powerful drug combinations available since the mid 1990s have transformed HIV infection into a manageable chronic condition rather than the death sentence it once was. But the drugs can cause heart and cholesterol problems, diarrhea, nausea and other side effects. They also must be taken faithfully or resistance develops and the drugs stop working.
That is why guidelines by the government and the International AIDS Society recommend that patients who are not yet having AIDS symptoms delay starting on the drugs until their T-cell counts fall below 350 per cubic millimeter of blood (healthy people have more than 800).
"There was this thinking, maybe the drugs were worse than the disease. If you could wait as long as you possibly could wait, you would have fewer side effects," said Dr. Robert Schooley, infectious diseases chief at the University of California at San Diego.
The new study is the largest to look at whether that advice is sound. Researchers led by Dr. Mari Kitahata of the University of Washington in Seattle pooled information on 8,374 people in the United States and Canada with T-cell counts of 351 to 500 from 1996 to 2006.
About 30 percent started taking AIDS drugs right away; the rest waited until their T-cell counts fell below 350, as guidelines recommend.
"We found a 70 percent improvement in survival for patients who initiated therapy between 350 and 500" compared with those who waited, Kitahata said.
Two other recent studies found that people who start taking AIDS drugs while their T-cell count is above 350 have a better chance of getting their count back to normal than those who start later. Another key study found that briefly interrupting treatment to give patients "drug holidays" puts them at grave risk.
"These studies have all shown the same thing — that we were starting too late" and need to keep treatment going once it starts, Schooley said. He helped write the AIDS society guidelines and consults for several companies that make AIDS drugs.
The bigger problem is that as many as a third of people diagnosed with HIV only discover they are infected after their T-cell counts already have fallen below 350 and they have serious complications.
Newer drug combinations that have come out in recent years have fewer side effects. Also, some require only a pill or two a day, making adherence less of an issue. These advances and the new study justify a fresh look at the guidelines, Fauci said.