The detection of non-adherence by self-administered questionnaires can be optimized by protease inhibitor plasma...

Area of Science:

• Pharmacokinetics and HIV Treatment Adherence
• Clinical Pharmacology of Antiretroviral Drugs

Background:

• Accurate assessment of medication adherence is crucial for effective Human Immunodeficiency Virus (HIV) treatment outcomes.
• Traditional self-reported adherence measures may not always reflect true patient compliance.
• Plasma protease inhibitor concentration (PPIC) can serve as an objective marker of adherence.

Purpose of the Study:

• To evaluate the utility of plasma protease inhibitor concentration (PPIC) in conjunction with self-reported adherence for detecting non-adherence in HIV-infected patients.
• To determine if PPIC can enhance the reliability of adherence assessment in patients on protease inhibitor-based regimens.

Main Methods:

• A cohort of 642 HIV-infected patients on a single protease inhibitor-containing regimen was studied at month 4.
• Self-reported adherence and plasma protease inhibitor concentration (PPIC) were measured.
• PPIC was assessed relative to the limit of quantification (LOQ).

Main Results:

• A significantly higher proportion of non-adherent patients (32%) had PPIC below the limit of quantification (LOQ) compared to adherent patients (8%).
• Considering adherent patients with PPIC below LOQ as non-adherent strengthened the association between non-adherence and detectable HIV viral load.
• The combination of PPIC and self-report demonstrated improved accuracy in identifying non-adherence.

Conclusions:

• Plasma protease inhibitor concentration (PPIC) is a valuable objective measure to supplement self-reported adherence in HIV management.
• Integrating PPIC measurements with patient self-reports provides a more robust and reliable method for detecting non-adherence to protease inhibitor therapy.
• Improved adherence monitoring can lead to better viral load suppression and patient outcomes in HIV care.