Epidemiological Trends of Diabetes Mellitus and Human Immunodeficiency Syndrome and Their Effect on Treatment Outcomes in Patients With Tuberculosis: A Situational Analysis of Tuberculosis Elimination Program Data From Tirunelveli District, 2017–2021

Background Tuberculosis (TB) was the leading cause of death due to a communicable disease before the COVID-19 pandemic. In 2021, India accounted for 25% of the world's TB cases. Tamil Nadu has a higher TB prevalence than the national average. Individuals with diabetes mellitus (DM) are two to four times more likely to develop active TB, while people living with human immune deficiency syndrome (PLHIV) have 20 times greater odds. This study aims to describe the epidemiological trends of comorbidities in TB cases over time and assess the relationship between comorbidities and treatment outcomes. Methods A secondary data analysis of NIKSHAY data was conducted for the Tirunelveli district from 2017 to 2021. Results The proportion of TB patients with DM increased significantly from 3.5% in 2017 to 27% in 2021. TB units in Pettai (25%) and Vadakkankulam (18%) had the highest percentage of patients with DM. HIV prevalence among TB patients was highest in Manur (2.2%), followed by Vadakkankulam (2.1%) and Papakudi (1.9%). Patients with DM had 33% higher odds of mortality compared to those without DM, while TB patients with HIV were 87% more likely to die from the disease (p < 0.000). Conclusion This study highlights the evolving trends of DM and PLHIV among TB patients and their impact on treatment outcomes in the Tirunelveli district. The effect of these comorbidities on mortality has been reiterated in this study.