Diabetics up to three times more likely to get severe TB, health expert warns

“Diabetes mellitus is associated with increased risk of tuberculosis; the risk [is] two to three times higher than [in] normal people,” said Dr. Anthony Harries, a senior adviser to the International Union against Tuberculosis and Lung Disease.

Experts estimate that a third of the world’s population is infected with TB. However in most people, the TB germs remain dormant and only one in 10 people on average go on to develop the active form of TB.

Harries said that if somebody who had a latent TB infection was later found to have diabetes, then the chance of the infection developing into a potentially deadly form of the lung disease multiplied.

“If you have diabetes and you have no germs inside you, you are no more at risk of getting infected than anyone else. However, if you are latently infected and you get diabetes you are more likely to develop active TB,” Harries said.

He added that people with diabetes who developed active TB were more likely to have the worst treatment outcome and were at higher risks of dying compared to TB patients without diabetes. Diabetes patients with active TB are also at risk of having recurrent TB even after they recover.

Diabetes is known to impair the human immune system and allow infections to fester for a longer period of time. Diabetes also complicates the TB control program and makes it more difficult for patients to recover.

Harries said that studies linking TB and diabetes were scarce and routine screening linking the two diseases was not common. Diabetic communities are also largely unaware of the implications of having both diseases at once.

Harries said there were some challenges in the management of diabetes-associated TB because doctors did not always screen their diabetes patients for TB.

“Maybe because the doctors are too busy or because this is a new intervention so they don’t know, or it could be because they don’t understand the health implications of TB,” he added.

The fact that most diabetes cases go undiagnosed and untreated also complicates the treatment for both diseases. Harries said half of those with diabetes did not realize they had the disease, and if they got TB the symptoms might appear different from TB in others, resembling pneumonia or other diseases and making it harder to diagnose.

Indonesia has high rates of both diabetes and TB. The most recent Tuberculosis Global Burden report from the World Health Organization puts the number of new TB cases in the country in 2011 at 450,000, making it the country with the fourth-highest number of TB cases after China, India and South Africa.

The WHO also ranks Indonesia ranked as fourth worldwide for the number of diabetes cases, after the United States, China and India. An estimated seven million Indonesians had the disease in 2010, according the WHO, with the figure expected to hit 21.3 million in 2030.

Tjandra Yoga Aditama, the Indonesian Health Ministry’s director general for disease control and environmental health, said his office had already acknowledged the TB-diabetes problem.

“Studies have been conducted among diabetics whose condition is well-managed, those who are poorly treated, and those who are not treated at all,” he said.

He added that while Indonesia faced a potentially high number of cases of TB-diabetes complications, the studies showed that people with well-managed diabetes were unlikely to develop active TB even if they were latently infected, compared to those who with inadequate treatment or no treatment.

“So the most important thing is to avoid the risk by managing the diabetes properly so that the infection doesn’t develop into active TB,” Tjandra said.

Source: The Jakarta Globe