Identification of risk factors for suboptimal adherence in people living with HIV through measurement of medication possession ratio: a cross-sectional study

The most significant progress in addressing the HIV/AIDS epidemic has been the development of antiretroviral therapy (ART). However, ensuring a high degree of treatment adherence is necessary to prevent resistance and disease progression. We conducted a cross-sectional study to evaluate adherence to ART through the calculation of the medication possession ratio (MPR) and to identify risk factors for suboptimal adherence in a cohort of HIV-positive patients receiving care at a Colombian healthcare institution across 16 cities. Records of 12,145 users were analyzed, and a multivariate logistic regression model was performed, considering optimal adherence (MPR > = 95%) versus suboptimal adherence (MPR < 95%) as the reference. Suboptimal adherence to ART was identified in 29% of users. Residence region, presence of HIV-defining illnesses, chronic kidney disease (CKD), co-infections such as hepatitis C, tuberculosis, and sexually transmitted infections, treatment duration of more than 5 years, and non-suppressed viral load were identified as risk factors for non-adherence. This underscores the need to identify interventions for those vulnerable groups to minimize the likelihood of non-adherence and to intervene in care models focused on the medical needs of these patients.