The medical community is wrestling with the fallout from a breakthrough study, presented late last month at the joint meeting of the American Society of Microbiology and the Infectious Diseases Society of America, suggesting that the current method of administering medication for HIV is not only not ideal—it may be compromising patients' long-term health.
The study was the work of a team of researchers from the University of Washington in Seattle and American and Canadian colleagues, who examined the records of nearly 8,374 HIV patients held in International Epidemiology Databases to Evaluate AIDS, a global network of HIV clinics from 1996 to 2006. Specifically, they were looking for the impact of starting retroviral medications sooner rather than later. Their finding: that delaying medication until the immune system was damaged nearly doubled a patient's risk of dying in the next few years.
For the last decade, HIV has become largely a manageable illness. Though the quest for a vaccine for the virus has proven frustratingly difficult, treatment is available (for those who can afford it) and effective. Yet until now, doctors have had little certainty about when to begin treating the illness with HAART, or "highly active antiretroviral therapy". And in general, they have tended to delay such treatments until they see signs of damage to the patient's immune system from the virus. That has meant counting the patient's CD4 T-cells, a type of immune cell, and beginning treatment at the point that the number of these cells falls below 350 per milliliter of blood (in a healthy person, the number would be closer to 800).
There have been many reasons for this protocol. In its original form, HAART was a difficult therapy to maintain. It typically has involved taking many pills each day. Side effects have also been crippling for many patients. Patients have to be very vigilant, as missing doses will lead to drug resistance and the treatment will cease to be effective, contrary to previously-prescribed "drug holidays", which now are viewed as profoundly dangerous. All of these factors led doctors to advise that people delay the treatment as long as realistically possible. "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, chief of infectious diseases at the University of California, San Diego.
The current study suggests that this is not an effective approach. Researchers found that initiating treatment immediately led to a nearly 70 percent improvement in survival. Specifically, the 30 percent of participants in the higher survival group began therapy when their CD4 counts were between 350 and 500, rather than allowing those levels to sink below 350, as would be the usual standard. This confirms and expands upon the conclusions of two other recent studies that found that people who began medication when their CD4 counts were above 350 were more likely to return their counts to normal than those who delayed treatment until the CD4 counts fell below 350. "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 U.S. National Institute of Allergy and Infectious Diseases, which helped fund the study.
Drug therapies for HIV have been consistently improving in recent years. Newer therapies have fewer side effects, and may only require taking one or two pills a day. As a result, the emphasis on early diagnosis could increasingly come to focus on reducing infection. Yet this study promises both to force the medical community to rethink its protocols for treating HIV, and to put pressure on public health campaigns aimed at diagnosis. Early diagnosis, it turns out, may well have serious implications not only for preventing the spread of the disease, but as part of an effective individual treatment approach. And in the near term, the study may mean that hundreds of thousands of HIV+ persons who are not currently on medication will be encouraged to start.