Less-than-perfect adherence to an HIV treatment regimen may not send viral loads into detectable territory but may give rise to harmful inflammation nonetheless.

Publishing their findings in Clinical Infectious Diseases, researchers studied 912 men in the Multicenter AIDS Cohort Study who made a cumulative 2,816 study visits between 1998 and 2009 at which tests showed that they had undetectable viral loads.

At these visits, the men reported whether during the previous six months, they took their antiretrovirals (ARVs) 100 percent of the time or less often than that and whether during the previous four days they adhered at a rate below 85 percent, between 85 to 99 percent or 100 percent.

After adjusting the data for age, race, hepatitis C virus (HCV) infection, smoking, depressive symptoms, diabetes, anemia, high blood pressure and CD4 count, the researchers found that when individuals reported that they had adhered at a rate below 100 percent during the previous six months, they had higher concentrations of various indications of inflammation compared with those who reported 100 percent adherence during the same span. The investigators found the same differences comparing those whose four-day adherence was below 85 percent to those with perfect four-day adherence.

After further adjusting the data for various factors, the researchers found that the marker of inflammation known as TNF-σ was 11 percent higher at visits when individuals said they adhered less than perfectly during the previous six months compared with those who said they adhered perfectly during that period.

The researchers theorized that low-level viral replication resulting from missing ARV doses might give rise to inflammation. They called for future research to investigate whether improving adherence to HIV treatment could impact inflammation and any associated illness or death.

To read the study abstract, click here.

To read a POZ feature on chronic inflammation, click here.