People who start antiretroviral treatment with CD4 counts above 350 have the lowest risk of disease progression and death compared with people who start at CD4 counts below 350, say the authors of a study published in the February 1 issue of the Journal of Acquired Immune Deficiency Syndromes (JAIDS) and reported by AIDSmap. The study lends further support to a trend, marked by recent changes to U.S. HIV treatment guidelines, suggesting that antiretroviral therapy should be started earlier than had been previously recommended.

A research team headed by Ángeles Jaén, MD, PhD, from the Centre d’Estudis Epidemiològics sobre ITS/VIH/SIDA de Catalunya in Badalona, Spain, reviewed the medical records from a large group of people living with HIV, called the PICSCIS cohort, being cared for at 10 hospitals throughout Spain. Nearly 7,000 people living with HIV were followed between 1998 and December 2004.

Dr. Jaén’s team closely evaluated records for 2,035 people who had started a three-drug combination antiretroviral regimen and who had their CD4 counts measured within six months before starting treatment. The patients were then split into three groups: those who waited to start antiretroviral therapy until their CD4 count had dropped below 200; those who started treatment at a CD4 count between 200 and 350; and those who started treatment with a CD4 count greater than 350.

A total of 148 patients progressed to AIDS or died over an average of roughly three years of follow-up. Using a relatively simple comparative analysis, the authors found that a number of factors were associated with an increased risk of disease progression. These included starting treatment with a CD4 count of less than 200, having a high viral load, being of older age, being an injection-drug user and being coinfected with hepatitis C (HCV).

After controlling for a number of factors, Jaén’s team found that people who started treatment with a CD4 count between 200 and 350 had a lower risk of disease progression than people who waited to start treatment until their CD4 count dropped below 200. Similar results from other studies recently inspired the United States and Europe to revise their HIV treatment guidelines, which now recommend that antiretroviral treatment be started in people with CD4 counts below 350. Jaén’s team asserts that the results of their study support those guidelines’ changes.

An additional finding, that the risk of disease progression in people who started treatment at CD4 counts above 350 was lower than in people who started treatment at CD4 counts between 200 and 350, lends credibility to the belief that even moderate levels of immune suppression may be harmful, and raises the question of whether starting treatment even earlier may be warranted.