Tuberculosis burden, knowledge and medication adherence among people living with HIV attending a tertiary hospital in south-eastern Nigeria

Tuberculosis (TB) remains the leading opportunistic infection and cause of mortality among people living with HIV (PLHIV), particularly in high-burden settings such as Nigeria. Despite advances in diagnosis and treatment, gaps persist in TB case detection, patient knowledge, medication adherence, and access to care. This study assessed the burden of TB, knowledge of TB among PLHIV, medication adherence, and barriers to treatment among PLHIV attending a tertiary hospital in south-eastern Nigeria. A facility-based cross-sectional study was conducted among 1,915 PLHIV receiving antiretroviral therapy at a tertiary hospital in Enugu State, Nigeria. Participants were recruited consecutively between January and August 2018. Data were collected using a structured questionnaire and supplemented with clinical records to confirm TB status. TB cases were defined as culture-confirmed diagnoses. Medication adherence was assessed using a self-reported 30-day recall. Data were analysed using descriptive statistics, chi-square tests, and multivariable logistic regression to identify factors independently associated with adherence. The mean age of participants was 37.1 ± 10.3 years, and 74.4% were male. The documented culture-confirmed TB among PLHIV was 36.5% (699/1,915). Knowledge of HIV and TB was generally high, with 94.0% correctly identifying airborne transmission of TB and 81.5% recognising increased susceptibility to TB among PLHIV. Self-reported medication-taking was high: 1,901 participants (99.3%) reported taking antiretroviral therapy during the recall period, while 678 of 699 participants with documented TB (97.0%) reported no missed TB medication dose in the preceding 30 days. These estimates should be interpreted cautiously because adherence was based on self-report and may be affected by recall and social desirability bias. The most commonly reported barriers to accessing care were long clinic waiting times (72.2%) and transportation challenges (64.3%). In exploratory multivariable analysis, medication adherence was associated with sex ( p = 0.036), age group ( p = 0.012 for 30–39 years versus 18–29 years), educational level ( p = 0.023 for secondary education and p = 0.004 for tertiary education versus primary or less), and employment status ( p = 0.006 for employed and p < 0.001 for self-employed versus unemployed). A substantial burden of TB exists among PLHIV in this setting despite high levels of knowledge and self-reported adherence. Structural barriers, particularly related to health system inefficiencies and transportation, remain key obstacles to optimal care. Strengthening TB/HIV collaborative programmes through patient-centred and decentralised service delivery is essential to improve access, sustain adherence, and reduce TB-related morbidity among PLHIV.