Diabetes epidemic threatens progress in tuberculosis control

A recent series published in The Lancet: Diabetes & Endocrinology suggests global efforts to control and eliminate tuberculosis could be hampered by the rapidly increasing rates of type 2 diabetes in low- and middle-income countries where tuberculosis is endemic.

According to the series, 15% of adult TB cases can be attributed to diabetes, leading to more than 1 million cases a year, with more than 40% in China and India alone. Researchers warn that if diabetes rates continue to rise, the present downward trajectory of TB cases could have an 8% less reduction or more by 2035.

“These findings highlight the growing impact of diabetes on TB control in regions of the world where both diseases are prevalent,” Knut Lönroth, PhD, of the Global TB Programme at WHO in Geneva, said in a press release. “TB control is being undermined by the growing number of people with diabetes, which is expected to reach an astounding 592 million worldwide by 2035.”

According to the first paper in the series, during the past 3 years, a 52% increase in diabetes prevalence in the 22 highest TB burden countries could be associated with a 5% increase in diabetes-associated TB cases from 2010 to 2013.

“People with diabetes have a three times greater risk of contracting TB than people without diabetes, are four times more likely to relapse following treatment for TB, and are at twice the risk of dying during treatment than those without diabetes. These figures suggest we need to improve care for these patients at multiple levels,” Reinout van Crevel, PhD, series co-author and infectious disease specialist at Radboud University Medical Center in the Netherlands, said in the release.

However, according to the third paper, improving care for diabetes — using improved case definition, glucose control in patients with diabetes, and chemoprophylaxis in people with latent TB infection — could reduce TB cases by 15% or more by 2035.

“If we are to achieve the ambitious post-2015 global TB target to reduce TB incidence by 90% by 2035, increased efforts to diagnose and treat both TB and diabetes, especially in countries with a high burden of both diseases, will be crucial,” Lönroth said.

An editorial accompanying the series indicates that without adequate resources to combat diabetes, progress in reducing TB and other communicable diseases cannot be made.

“Importantly, the intersection between communicable diseases and [non-communicable diseases] should be used as a driver to strengthen health systems, to ensure that they can provide access to care with financial risk protection for all disorders, not just a select few,” researchers wrote. “Illness, death and disability do not recognize the divide between communicable and [non-communicable diseases], and nor should our delivery of health care.”

For more information:

Lancet Diabetes Endocrinol. 2014;2:677.

Lönroth K. Lancet Diabetes Endocrinol. 2014;2:730-739.

Odone A. Lancet Diabetes Endocrinol. 2014;2:754-764.

Riza AL. Lancet Diabetes Endocrinol. 2014;2:740-753.

Disclosure: See the full series for a complete list of the researchers’ relevant financial disclosures.