Tuberculosis, DM, and Socioeconomic Inequities

1. Disparities and Risk Factors in TB Diagnosis and Treatment

• Demographic disparities impact TB diagnosis and treatment: In Brunei, male contacts, household contacts, and exposure to smear-positive PTB cases increased LTBI risk. Foreign nationals and young children were less likely to initiate LTBI treatment. In US-born populations, Black individuals accounted for 38% of TB cases and 42% of TB-related deaths, with significant disparities persisting in marginalized racial and ethnic groups. Native Hawaiian/Other Pacific Islanders are projected to experience 75% disparity-associated TB cases by 2035.
• Socioeconomic factors contribute to TB risks: In Yogyakarta, low-income DM patients were at higher risk of developing pulmonary TB. In ASEAN, countries with lower health expenditure (e.g., Myanmar) had higher TB burdens. See also: Benang Merah Research Center
• Gender differences: Female DM patients in Yogyakarta had a 9.6 times higher risk of TB (borderline significance). In Brunei, female healthcare workers showed higher LTBI treatment acceptance, but in other settings, men exhibited delayed healthcare-seeking behavior and poorer adherence.

---

2. TB and Comorbidities: Diabetes and Hyperglycemia

• Diabetes Mellitus (DM) significantly increases TB risk and worsens outcomes: Poor glycemic control (HbA1c > 7.0%) doubles the risk of TB. DM-TB patients exhibit higher HbA1c levels compared to DM-only patients.
• Hyperglycemia’s impact on TB: Long-term elevated glucose weakens immune responses, promoting TB progression. In China, age-standardized TB mortality related to hyperglycemia showed the greatest reduction in the 60-64 age group, identifying it as a key intervention period.
• Gender and metabolic factors: Men have higher TB mortality rates, potentially due to biological differences (e.g., estradiol enhances macrophage activation in women). Poor glucose control management is especially problematic in men due to behavioral factors like poor adherence.

---

3. Treatment Challenges: Loss to Follow-Up and Completion Rates

• Treatment initiation and completion remain suboptimal: In Brunei, only 43% of LTBI cases initiated treatment, with 74% of those completing it. Progression to active TB occurred in 0.5% of LTBI cases, mostly within 8 years, even after treatment completion.
• Loss to Follow-Up (LTFU): Driven by low education, short-term migration, limited access to healthcare, low income, and unemployment. Behavioral factors such as alcohol use and smoking increase LTFU risk by impairing adherence.
• Migrants face compounded barriers: unstable housing, irregular employment, and lack of healthcare continuity lead to higher LTFU rates.
• Protective factors include health insurance and travel support, which ease financial and logistical barriers to treatment adherence. See also: Yoseph L. Samodra

---

4. Regional Trends and Economic Burden of TB

• ASEAN regional trends (2002-2017): Six countries (Cambodia, Myanmar, Indonesia, Vietnam, Laos, Thailand) saw a steady decline in TB incidence. The Philippines reversed its initial decline post-2007, and Malaysia saw rising cases from 2009 onward. Singapore and Brunei had the lowest TB case numbers, correlating with their higher per capita health spending.
• US Projections (2023-2035): 26,203 TB cases and 3,264 deaths projected among US-born persons. Racial and ethnic disparities will drive 45% of TB cases and up to 66% of the projected $1.397 billion economic burden.
• Economic disparities and TB burden: Countries and populations with lower healthcare investment or access continue to experience higher TB rates and poorer outcomes. Addressing disparities is essential for reducing TB incidence and economic costs.

References:

1. Chaw, L., Hamid, R.A., Koh, K.S. and Thu, K., 2022. Contact investigation of tuberculosis in Brunei Darussalam: Evaluation and risk factor analysis. BMJ open respiratory research, 9(1).
2. Syafiq, N.J.M., Trivedi, A.A., Lai, A., Fontelera, M.P.A. and Lim, M.A., 2023. Latent tuberculosis infection in health-care workers in the government sector in Brunei Darussalam: A cross-sectional study. Journal of Integrative Nursing, 5(3), pp.197-202.
3. Swartwood, N.A., Li, Y., Regan, M., Marks, S.M., Barham, T., Asay, G.R.B., Cohen, T., Hill, A.N., Horsburgh, C.R., Khan, A.D. and McCree, D.H., 2024. Estimated Health and Economic Outcomes of Racial and Ethnic Tuberculosis Disparities in US-Born Persons. JAMA Network Open, 7(9), pp.e2431988-e2431988.
4. Nuraisyah, F., Juliana, N., Astaria, D., Khalisah, N., Al Fatih, D.M.F., Dewi, S.K. and Marwati, T., 2024. Risk Factors of Pulmonary Tuberculosis in Type 2 Diabetes Mellitus in Yogyakarta. Journal of Epidemiology and Public Health, 9(2), pp.194-203.
5. Shanmuham, V., Shetty, J.K. and Naik, V.R., 2022. Incidence of tuberculosis in the association of South-East Asia Nation (ASEAN) countries and its relation with health expenditure: a secondary data analysis. Manipal Journal of Nursing and Health Sciences, 8(1), p.7.
6. Rani, A.Y.A., Ismail, N., Zakaria, Y. and Isa, M.R., 2024. A scoping review on socioeconomic factors affecting tuberculosis loss to follow-up in Southeast Asia. Med J Malaysia, 79(4), pp.470-476.
7. Chen, Z., Liu, Q., Song, R., Zhang, W., Wang, T., Lian, Z., Sun, X. and Liu, Y., 2021. The association of glycemic level and prevalence of tuberculosis: a meta-analysis. BMC Endocrine Disorders, 21(1), p.123.
8. Wang C, Yang X, Zhang H, Zhang Y, Tao J, Jiang X and Wu C (2023) Temporal trends in mortality of tuberculosis attributable to high fasting plasma glucose in China from 1990 to 2019: a joinpoint regression and age-period-cohort analysis. Front. Public Health 11:1225931.

TBC 049