In a study conducted at the University of Montreal, in collaboration with the Clinique medicale du Quartier Latin de Montreal, researchers found that in patients with HIV, a persistent low viral load (specifically defined as between 50 and 199 copies of viral RNA per milliliter of blood) carries a much higher risk than previously thought.
The study was based on data pulled from the files of 1,860 patients living with HIV/AIDS over the course of 12 years; nearly 94 percent were male.
In HIV treatment, the goal is to reduce a patient’s viral load to below the detectable limit, less than 50 copies/ml. The higher a patient’s viral load, the more the immune system is compromised, which causes the progression of HIV to AIDS. The development of anti-retroviral drug regimens in 1996, which inhibits the spread and increase of the virus, was what finally turned HIV/AIDS from an imminent death sentence into, largely, a chronic health condition.
In some cases, HIV infection is resistant to treatment; this can lead to virologic failure. In a statement, University of Montreal researcher Claudie Laprise explained, “Virologic failure, defined in this study as a viral load above 1,000 copies/ml of viral RNA in the blood, is to be avoided…because it shows the progression of the disease.”
Laprise found that, as suspected, persistent viral load is directly linked to risk of virologic failure. Patients with an “average” viral load (200 to 499 copies/ml) have five times the risk of those with undetectable levels of the virus; however, even those with “low” viral loads—50 to 199 copies/ml—have twice the risk of seeing their treatments fail. She told the Montreal Gazette, “That really surprised us because we didn’t believe that a load of 50 could have such a risk.”
The results of the study show that there is a need to develop clinical guidelines for managing HIV in people with persistent viral loads, regardless of level. More studies are needed to fully understand the variables present, but patients as well as doctors need to know what is considered a risk.
Laprise added, “To the extent that our results are confirmed by other studies, our findings could provide a new element in assessing the situation of people with HIV, because of the potential risk factors our data have uncovered.”