Diabetes Compounds TB Risks, Raising Global Health Concerns

Experts warn that diabetes significantly weakens the immune system, exacerbating the health risks associated with tuberculosis (TB). On March 5, 2024, senior medical scientist Hemant D Shewade from the ICMR-National Institute of Epidemiology in Chennai highlighted the concerning interplay between these two global health challenges. The combination of diabetes and TB poses a severe threat not only to individual patients but also to communities and healthcare systems worldwide.

India faces a critical public health challenge, with approximately 2.8 million reported cases of TB, which represents 26 percent of the global burden in 2024. The country also recorded around 315,000 TB-related deaths, accounting for 29 percent of global fatalities from the disease. At the same time, the prevalence of diabetes is rising sharply, affecting over 100 million individuals in India.

In a recent study published in the journal PLOS One, Shewade and his team found that individuals suffering from both TB and diabetes are significantly more vulnerable. They are two to three times more likely to remain culture-positive for TB and face a fourfold increase in relapse rates after treatment. Alarmingly, these patients are five times more likely to die compared to those without diabetes.

The treatment for TB complicates the management of diabetes. Shewade emphasized the urgent need to enhance tracking of blood sugar levels in patients co-infected with TB and diabetes, especially those identified through the national TB program. Current guidelines treat diabetes management identically for TB patients and non-TB patients, but this approach may need reevaluation.

“There is a pressing need for more evidence on whether strict glycemic control (HbA1C below 7 percent) is necessary, or if a less stringent target (HbA1C below 8 percent) suffices for patients with TB,” Shewade stated. He also suggested the introduction of the capillary fasting blood glucose (cFBG) test as a useful tool for monitoring glycemic status in this population.

The risks are particularly acute for those with type 1 diabetes. Studies indicate that patients with diabetes face a 3.5 to 5.0-fold higher risk of developing TB, with even greater dangers observed in individuals with type 1 diabetes. Delayed diagnoses further exacerbate these risks, leading to high relapse rates and increased mortality.

The World Health Organization (WHO) advises that individuals with diabetes who experience a cough lasting more than two weeks should be evaluated for TB. Despite this guidance, there is limited knowledge regarding the prevalence of pulmonary tuberculosis (PTB) specifically in type 1 diabetes patients.

Dr. Urvashi Singh from the All India Institute of Medical Sciences in New Delhi led a recent investigation published in the journal Multidisciplinary Respiratory Medicine. The study examined 151 type 1 diabetes patients at a tertiary-care outpatient clinic, revealing that approximately 10.6 percent tested positive for sputum culture. This rate was particularly pronounced among those with a previous history of PTB.

Singh emphasized the importance of actively screening type 1 diabetes patients for PTB to facilitate early treatment and prevent community transmission. “Given the high prevalence of PTB in this demographic, it is crucial to implement regular screening practices,” she stated.

The intersection of diabetes and tuberculosis represents a significant public health challenge, particularly in high-burden regions like India. Enhancing awareness, improving treatment protocols, and fostering research into effective management strategies could mitigate the impact of both conditions. As these health crises evolve, careful monitoring and innovative solutions will be essential in safeguarding the health of millions.