The following is a summary of “Overreporting of adherence to hepatitis C direct-acting antiviral therapy and sustained virologic response among people who inject drugs in the HERO study,” published in the February 2024 issue of Infectious Diseases by Lopes et al.
Limited research explores the correlation between self-reported adherence to hepatitis C direct-acting antivirals (DAAs) among people who inject drugs (PWID) and objectively measured adherence, as well as its impact on sustained virologic response (SVR).
Researchers conducted a retrospective study among PWID to investigate a threshold for overreporting adherence that best predicts decreased SVR rates and to explore factors associated with this optimal overreporting threshold.
They analyzed per-protocol data (N = 493) in the HERO (Hepatitis C Real Options) study, all of whom had adherence data available. Self-reported adherence and objectively measured adherence for a 12-week DAA regimen were assessed using visual analog scales and electronic blister packs. The study calculated the difference (Δ) between self-reported and objectively measured adherence. Utilizing the Youden index from receiver operating characteristic (ROC) curve analysis, they determined an optimal threshold of overreporting to predict lower SVR rates. To identify factors associated with this optimal threshold of overreporting, they compared baseline characteristics between participants at or above the threshold and those below it.
The results showed that the self-reported, objective, and Δ adherence averages were 95.1% (SD = 8.9), 75.9% (SD = 16.3), and 19.2% (SD = 15.2), respectively. The ≥ 25% overreporting threshold was found to be optimal. The SVR rate was lower for ≥ 25% vs < 25% overreporting (86.7% vs 95.8%, P<.001). Factors associated with ≥ 25% Δ adherence included unemployment; a higher number of days and times/day of injecting drugs; a higher proportion of positive urine drug screening for amphetamine, methamphetamine, and oxycodone, and negative urine screening for THC (tetrahydrocannabinol)/cannabis.
Investigators concluded that PWID significantly overreports DAA adherence compared to objective measures, and higher overreporting is linked to lower cure rates, suggesting a need for closer management of PWID at risk of overreporting.
Source: bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-024-09124-3