Socio-demographic and AIDS-related factors associated with tuberculosis stigma in southern Thailand: a quantitative, cross-sectional study of stigma among patients with TB and healthy community members

Tuberculosis (TB) remains one of the most important infectious diseases worldwide with an estimated 9.4 million new cases and 1.7 million deaths in 2009 [1]. In addition to the focus on treatment and cure rates, a more comprehensive approach towards disease control is now advocated, in order to address poverty and other social risk factors, of which stigma is one component [2]. Stigma was originally described by Goffman as "an undesirable or discrediting attribute that an individual possesses, thus reducing that individual's status in the eyes of society" [3]. More recently, health related stigma has been defined as "a social process or related personal experience characterized by exclusion, rejection, blame, or devaluation that results from experience or reasonable anticipation of an adverse social judgment about a person or group identified with a particular health problem" [4]. This conceptualization highlights two important components of stigma: overt patient experiences of discrimination in their community and the internalized fear and anticipation of social consequences regardless of any actual experience by the patient. Defining stigma as a "social process" draws attention to the important interactions between those who have the "health problem" (e.g. patients with TB) and those who do not (e.g. healthy community members)[5].

Individuals diagnosed with TB report fears of isolation and rejection such as losing employment, being divorced or having diminished marriage prospects, not being allowed to share meals, utensils or sleeping quarters with family members, and general avoidance or gossip among community members [6‐9]. Fear of these consequences may lead to delays in seeking care for TB symptoms and could affect adherence to treatment [6, 7, 10]. Because of this, TB stigma continues to be viewed as a barrier to TB control.

Qualitative studies using focus groups and interviews have identified religion, socioeconomic status, level of education, and gender as possible factors associated with TB stigma [11, 12], with women more often than men feeling the effects of TB stigma [6, 8]. Reasons why TB may be stigmatizing include contagiousness [7, 13, 14], incorrect knowledge of its cause, transmission, or treatment [7, 8, 12, 13, 15], or its association with marginalized groups such as the poor, ethnic minorities, sex workers, prisoners, and those infected with HIV [7, 8, 12, 13, 16, 17]. As the epidemics of TB and HIV/AIDS have converged in many areas of the world, there is growing concern that AIDS and AIDS stigma may compound existing TB stigma [13, 18, 19]. For some, a TB diagnosis is thought to be synonymous with an AIDS diagnosis, or TB symptoms may be misidentified as AIDS symptoms [12, 14, 18‐20].

While qualitative studies help identify possible factors associated with stigma, quantitative measures are needed to assess the level of stigma in a population, factors most strongly associated with stigma, and evaluate the effectiveness of interventions [4]. Unfortunately, few quantitative studies have been done to assess factors associated with TB stigma [21]. Except for one study [22], previous quantitative studies used brief scales that were not formally developed or not evaluated for internal consistency [23, 24]. Furthermore, each of these quantitative studies measured TB stigma among patients only. Given the lack of empirical studies on TB stigma, it cannot be assumed that stigma levels and associated factors in patients with TB are identical to the stigma levels in the community and the factors associated with community stigma.

We used formally developed and validated scales [25] to measure the level of TB stigma among patients with TB and healthy community members. The primary purpose of this study was to test if socio-demographic characteristics, TB knowledge, TB clinical factors, and AIDS stigma were associated with higher TB stigma among two different populations: patients with TB and healthy community members. Identification of factors that affect stigma, particularly among both groups, would help inform interventions at the patient, provider, organizational, and community level.

Most factors analyzed in this study had only minimal or inconsistent associations with TB stigma. Only poor education (some or no primary education) and AIDS stigma showed a consistent association with higher TB stigma in all three analyses. In addition to low levels of formal education, the largest, most precise, and consistent associations with higher TB stigma were beliefs relating to the intersection of TB with HIV, HIV co-infection, and the level of AIDS stigma. Knowing someone who died of TB had the largest association with TB stigma. Individuals in areas affected by HIV are more likely to believe that TB is not curable [13, 22]. Thus, higher TB stigma due to knowing someone who has died of TB may be linked to HIV co-infection via the belief that TB is not curable, a result that was observed, but not statistically supported, in our study.

Most prior studies on TB stigma have been qualitative. A qualitative study in the same area of southern Thailand found that religion, low TB knowledge, severe symptoms, and symptoms similar to AIDS were related to stigmatizing attitudes towards TB [12]. While some of these qualitative observations were confirmed by our quantitative findings, most factors identified as being associated with TB stigma in the qualitative study showed small, inconsistent or imprecise effects in our study. Only among community members was the belief that eating and drinking with a patient could transmit TB found to be associated with a larger increase in stigma. These studies underscore the importance of quantitative analyses to assess the generalizability and magnitude of associations observed in qualitative studies.

To date, only three other quantitative studies of TB stigma and potential factors associated with TB stigma have been published [22‐24]. Detailed comparisons between them warrant caution, as different scales, study populations, and potential factors were used. Similar to our findings, however, lack of consistent associations between factors and stigma among different populations was observed by Somma et al.[22] from a study in Bangladesh, India, Malawi and Colombia. In that study, only marital status, financial problems, social distress, and seeking care at a private hospital were found to increase stigma in more than one study site.

Documenting the level of TB stigma and identifying factors associated with stigma are important steps towards developing interventions to reduce stigma [4]. It is generally believed that increasing TB knowledge and education are important interventions to decrease stigma [8, 31]. We found, however, that TB knowledge itself has a minor and inconsistent association with TB stigma. We did find that incorrectly believing TB can increase the chance of getting AIDS was associated with higher stigma among patients. This is most likely due to the rate of TB/HIV co-infection and/or that patients with TB are routinely tested for HIV. Thus, having TB increases the chances of being diagnosed with, but not being infected with, HIV. In our study, belief that TB increases the chance of getting AIDS, AIDS stigma, co-infection with HIV, and knowing someone who died from TB had the strongest, most precise, and most consistent association with higher TB stigma. This is consistent with the suggestion that AIDS and AIDS stigma may compound existing TB stigma [13, 18, 19] and suggests that interventions aimed at decreasing TB stigma should also address the HIV/AIDS epidemic. This may include media and public education campaigns to raise awareness that TB occurs and is curable, both in HIV-infected individuals and those not infected with HIV. This could coincide with the message that people living with HIV should be watchful for symptoms of TB and seek medical care if they develop common TB symptoms, with making HAART available to all patients needing treatment for HIV, and providing isoniazid preventive therapy (IPT) to patients with HIV. It has been suggested that scaling up the provision of HAART may decrease AIDS stigma by reducing AIDS mortality and allowing for normalization of patients [32‐34], while provision of IPT would reduce the burden of HIV-related TB morbidity and mortality, thereby changing the perception that patients with HIV also develop TB [35‐37].

Some limitations of our study should be noted. First, the small number of responses for some causes and transmission routes of TB could have led to low power to detect a true association with stigma. Second, it is possible that associations were biased as high levels of stigma may have caused patients to avoid seeking any care for their symptoms, high levels of stigma may have been the reason why some eligible patients refused to participate in the study, or a period of coping could have occurred between the onset of symptoms and presentation at the clinic, resulting in lower levels of stigma. This could explain, in part, why patients with TB reported lower TB and AIDS stigma than community members, because there is no reason to think any selection bias occurred among community members. Finally, we did not assess factors associated with stigma during TB treatment.

Few quantitative studies on TB stigma and potential factors associated with TB stigma have been published. We report the presence of TB stigma in both patients and community members in southern Thailand. Our results suggest that interventions addressing the dual TB/HIV epidemic may be needed to combat TB stigma, and that simply improving knowledge about TB may have limited effects.