Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis, which primarily affects the lungs (pulmonary TB) and other organs (extrapulmonary TB). Although the disease is curable and preventable, alongside HIV, TB ranks as a leading cause of death worldwide (World Health Organization, 2023). South Africa ranks 8th globally in terms of TB cases, accounting for 3.3% of the total global TB cases (Olivier and Luies, 2023). Although the country has made some progress in TB control in recent years, it still falls short of the WHO’s 90% standard for treatment success across all countries (Stop TB Partnership, 2017). A South African study, which was conducted to explore the presence of TB stigma within communities, showed that TB stigma is mainly driven and facilitated by fear of disease, coupled with an understanding of TB/HIV duality, and manifests as anticipated and internalized stigma. This means that individuals were verbally labeled with TB stigma through gossip and visually through symptomatic identification or when accessing care in either a TB-specific area in health clinics or through ward-based outreach teams (DeSanto et al., 2023). In essence, TB has increasingly become more stigmatized, especially among populations with high rates of TB and HIV co-infections (Craig et al., 2017) because of its biological, epidemiological, and social interactions with HIV/AIDS (Bresenham et al., 2020). Tuberculosis-related stigma continues to pose a formidable challenge for TB prevention and control (Datiko et al., 2020) and has been identified as an obstacle to patients seeking medical care and completing a full course of treatment (Chen et al., 2021). Patients may not take their medication as prescribed or avoid disclosing their TB status for fear of being judged, isolated, and rejected by others. Therefore, higher stigma negatively affects adherence (Pradhan et al., 2022). Both enacted and internalized stigma are experienced by people diagnosed with TB. Internalizing stigma may increase the risk of mental and physical health problems, which can have negative consequences for treatment adherence (Blake Helms et al., 2017). Feldhaus et al. (2018) found that self-stigmatization has a significant influence on patients’ medication adherence attitudes. Furthermore, internalized stigma (self-stigma) is linked to increases in psychological distress and poorer quality of life (Cheng et al., 2019; Sarkar et al., 2019). TB patients’ behavior in response to social discrimination can contribute to diagnostic delays, non-adherence, and the abandonment of treatment, which can result in an increased number of multidrug-resistant tuberculosis cases (Marahatta et al., 2020; de Almeida Crispim et al., 2017). The impact of TB stigma remains underexplored and underappreciated (Bresenham et al., 2020), and more research, using validated instruments to quantify the impact of stigma on treatment compliance, is needed (Maleche et al., 2017). This study aimed to examine the predictive ability of enacted and internalized stigma for TB outcomes using a quantitative research approach.

Tuberculosis stigma remains a barrier to early diagnosis and treatment completion (Mbuthia et al., 2020). In the context of on-completion of treatment for TB, patients’ failure to adhere to TB treatment is a major significant challenge that contributes to poor treatment outcomes (Gashu et al., 2021). Medication non-adherence is not only associated with poorer health outcomes but is one of the most significant obstacles to TB control globally (Kvarnström et al., 2021; Gebreweld et al., 2018). Furthermore, Subu et al. (2021) argue that stigma generally leads to negative social experiences, such as isolation, rejection, marginalization, and discrimination. Thus, if stigma is related to a health condition, it may affect a person’s illness and treatment course, including access to appropriate and professional medical treatment (Subu et al., 2021).

Given that stigma emanates from multiple levels outside the individual (i.e., family, community, institutions), understanding TB stigma is essential for improved interventions to minimize its effects (Mbuthia et al., 2020). The National Strategic Plan for HIV, TB, and sexually transmitted infections recognizes both HIV-related and TB-related self-stigma as major public health concerns. As a result, it aimed to halve both HIV-related and TB-related self-stigma by 2022 (National Department of Health, 2017). Evidence suggests that TB stigma in relation to treatment adherence and completion has been replete with contradictory results despite using prospective designs (Yan et al., 2018). A plausible explanation for these contradictions is the use of unvalidated scales to distinguish between and measure the different domains of stigma (Bresenham et al., 2020). Thus, additional quantitative work is warranted to assist stakeholders, such as TB program implementers or policymakers, in understanding the magnitude of stigma’s impact in specific settings or distinct subpopulations (Bresenham et al., 2020). The current findings fill this gap by using a validated stigma scale that measures both internalized and enacted stigma experienced by DS-TB patients.

The current findings supported that stigma (both internalized and enacted) predicted successful treatment outcomes. Patients with low levels of internalized and enacted stigma were 2.6 and 2.9 times (respectively) more likely to have successful TB treatment outcomes compared to patients with high internalized and enacted stigma. The impact of stigma is confirmed by several studies related to other chronic illnesses. In a scoping review of health-related stigma outcomes for high-burden diseases (like TB) in low and middle-income countries (Kane et al., 2019), stigma was associated with decreased medication adherence and, among patients with substance use, relapse. Another study conducted on TB and its determinants in Dalian, Northeast China, showed that stigma (i.e., experienced, anticipated and internalized) among TB patients was high (Chen et al., 2021). There is a growing awareness of the need to address the stigma related to TB (Craig et al., 2017), since stigma has long been recognized as a factor influencing medication adherence (Náfrádi et al., 2017). This could be because patients may not want others, or anybody, to know about their illness, owing to the fear of being stigmatized. The fear can be so intense that the patient would prefer not to take medication if there is a possibility that someone might be watching (Kvarnström et al., 2021).

The fear of TB transmission was also identified by Mbuthia et al. (2020) as a key driver of TB stigma among TB patients in a rural Kenyan community. Furthermore, TB stigma was represented through patients being isolated by others, self-isolation, fear of disclosing a TB diagnosis, association of TB with HIV, and lack of social support (Bresenham et al., 2020; Mbuthia et al., 2020). A study conducted by Abdisa et al. (2020) on self-stigma and medication adherence among patients with mental illness in South West Ethiopia found that self-stigma was a contributing factor to non-adherence to medication. That non-adherence contributes to increased healthcare costs (Abdisa et al., 2020).

In the context of South Africa, TB stigma has been investigated alongside HIV stigma owing to the contextual double burden of disease (DeSanto et al., 2023; Wouters et al., 2020). Recent statistics from TB DIAH Project (2024) highlight low levels of TB treatment success in South Africa (78.97%), but this study reported a success rate of 86%. This may be due to the low stigma experienced by the study participants, which, in turn, would not only foster a positive attitude toward treatment but also promote treatment compliance. DeSanto et al. (2023) recommended community and individual education campaigns on TB treatment and transmission, as well as training for health care workers on stigma and stigmatization interventions to prevent discrimination and protect patient confidentiality.

TB remains a pressing health concern in South Africa. Therefore, understanding stigma and how it interacts with patient progression along the TB cascade provides insight into specific groups of patients, especially those at greater risk for poor TB outcomes. This study supports the notion of Pradhan et al. (2022) of the urgent need to integrate mental health services into TB control programs. Based on the study’s findings, it is recommended that interventions be implemented to minimize stigma and lower the likelihood of early treatment interruption. Bresenham et al. (2020) recommend education initiatives to raise awareness and knowledge of TB treatment, aimed at minimizing social stigma. It is also recommended that further studies be conducted to understand how TB stigma functions and influences community perceptions. This information will not only contribute to lessening TB stigmatization but also improve treatment and retention in care. The TB program, health professionals, and policymakers are urged to consider the study’s recommendations for overcoming self-stigma to promote medication adherence among patients with TB disease.

A limitation of this study is that the sample of 90 participants who were receiving TB treatment was a convenience sample and not representative of all DS-TB patients in the country. The findings can thus not be generalized. In addition, the study design did not use randomization and a control group, therefore limiting its ability to establish a cause-and-effect relationship and increasing the risk of various biases. The experiences of low stigma may have been influenced by the registered nurses who could have interfered by motivating participants to take their medication to get better. The SSCI-8, however, was reliable and showed high internal consistency.

The study showed that low stigma is associated with favorable TB outcomes among newly diagnosed TB patients. The measurement of stigma among TB patients can thus predict successful treatment outcomes. Taking a proactive approach is key to identifying earlier stigma experienced by DS-TB patients. Those experiencing stigma can be supported through interventions aimed at stigma reduction, improved treatment, and retention in care, ultimately yielding successful treatment outcomes.

The findings of this study can thus be used to design effective interventions that promote stigma reduction to reduce the probability of early treatment interruption. In addition, these interventions will not only help reduce TB stigmatization but also improve treatment and retention in care. The study thus contributes to understanding stigma in PWTB for policy development and interventions aimed at improving TB treatment outcomes.