How quickly an HIV patient’s immune system deteriorates may not affect the outcome of the illness, a study has found, and this could help change current guidelines for treatment of the disease.

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 do not start treatment until there is some evidence of damage to this system, measured by counting the number of immune cells, called CD4 T-cells.

In developed countries, HIV treatment usually begins when CD4 numbers drop below 350 cells per microlitre of blood.

Some treatment guidelines also recommend that therapy be started more quickly for people whose CD4 counts decline rapidly.

But the study, involving an international team of researchers, found that the pace of decline did not result in any substantial differences to the outcome of the illness.

“What we looked at was whether it matters how a person reached his current CD4 cell count, whether the CD4 count declined very quickly, or very slowly, and we found that the CD4 cell dynamics don’t provide additional information about the patient’s prognosis on top of the current CD4 cell count,” said Marcel Wolbers of the Hospital for Tropical Diseases in Ho Chi Minh City in Vietnam.

Wolbers, a biostatistician and one of the principal investigators of the study, and his colleagues examined records of 2,820 HIV patients from Australia, Canada and Europe with varying rates of CD4 declines.

They found no significant differences in their progression to AIDS or the number of deaths.

“The current rate of CD4 cell decline is neither a strong predictor of whether a person is progressing to AIDS or dies, nor does it predict future CD4 cell decline,” he said. “Therefore, it shouldn’t guide clinical decisions, in particular the decision whether to initiate (drug) therapy or not.

“A further implication of our study is that the patient’s CD4 cell count should be monitored regularly regardless of the prior rate of CD4 decline and that should be done according to current guidelines, i.e. every three to six months.”

The study was published in the latest issue of PLoS (Public Library of Science) Medicine. ‘

HONG KONG (Reuters)