Adherence to Antiretroviral Therapy among Patients with Human Immunodeficiency Virus: Rates and Determinants

Background: Achieving optimal adherence to antiretroviral therapy (ART) is critical for viral suppression in individuals living with human immunodeficiency virus (HIV). Objectives: This study assessed adherence rates among individuals on ART using pharmacy refill data, identified sociodemographic and clinical factors influencing adherence, and evaluated the relationship between adherence and viral load outcomes. Material and Methods: A retrospective longitudinal study was conducted among participants with HIV at a secondary public healthcare facility in Maiduguri, Nigeria. Patients 18 years and older who had filled records at the HIV clinic of at least 12 months’ supplies of ART were included in the study. Sociodemographic characteristics and viral load values were extracted from medical records. Adherence was measured using the proportion of days covered method, which was determined based on ART dispensing records from January to December 2023. Chi-square test and logistic regression analyses were used to identify factors associated with adherence, while correlation analysis was performed to investigate the relationship between adherence and viral suppression. P < 0.05 was considered statistically significant. Results: Among 300 participants included in the study, 61.0% were female, and 53.3% were aged 30–49 years. ART good adherence rate of 97.7% was found in the study population. Adherence was significantly associated with marital status ( P = 0.012) and viral load levels ( P = 0.011). Married individuals (61.4%) showed better adherence compared to single participants (38.6%). Participants with viral loads of <20– 75 copies/mL were more likely to adhere, while those with >200 copies/mL demonstrated poorer adherence (adjusted odds ratio = 0.07, P = 0.035). A significant negative correlation was observed between adherence and viral load (r = −0.360, P < 0.001). Conclusion: This study found that an overwhelming proportion of the study participants demonstrated good ART adherence. Sociodemographic characteristics, particularly marital status, and baseline viral load levels, significantly influenced adherence. Tailored interventions targeting the identified vulnerable groups are essential to improving adherence and optimizing treatment outcomes among people living with HIV.