A case-control study of factors associated with non-adherent to antiretroviral therapy among HIV infected people in Pwani Region, eastern Tanzania

Non-adherence is one of the major causes of treatment failure which leads to increased morbidity and mortality caused by opportunistic infections. Optimal anti-retroviral therapy (ART) adherence is essential for maximal suppression of viral replication and long term survival of patients. In order to develop effective public health interventions in the context of scaling ART services to peripheral areas, it is important to evaluate factors associated with non-adherence among HIVinfected individuals in Pwani Region. The purpose of this study was to identify factors related to nonadherence to ART among HIV infected people in Pwani Region eastern of Tanzania. A case-control study was carried out at Tumbi Hospital and Chalinze Health Centre in Pwani Region in eastern Tanzania. A structured questionnaire was used to assess non-adherence and adherence to doses instruction and time schedule. Patients with less than 95% adherence were defined as cases while those with more than 95% adherence became controls. A structured questionnaire containing factors known to be associated with non-adherence to ART in similar settings was administered. Univariate and multivariate conditional logistic regression was performed to identify factors associated with non-adherence. A total of 79 cases and 237 controls matched by age and sex were studied. A high proportion of cases and controls (77.2% and 84.8%) had good knowledge of ART benefits, adherence and eligibility. Majority of cases (73.3%) and controls (69.2%) used public transport to access ART services. More than half of cases (53.2%) missed clinic appointments due to lack of bus fare or other reasons and was associated with ART non adherence (mOR 4.2, 95%CI, 2.2-8.1 and 2.1,95%CI 1.2-4.2). Disclosure to confidants only and failure to disclose HIV-test positive status were associated with non adherence (mOR 3.3, 95%CI 1.3-8.5 and 2.3, 95%CI 1.2-7.1). Alcohol use was associated with non adherence to ART (mOR 1.9, 95%CI 1.4-3.7). Patients who were not satisfied with providers were more likely to be non adherence to ART (mOR 2.0, 95%CI 1.2-3.8). In conclusion, these findings show that adherence is a process which is depended on local specific adherence factors. Adherence improvement strategies need to consider site specific adherence determinants, patient experiences and concerns.