HIV is known to fuel tuberculosis (TB), but the lesser-known threat of diabetes actually places people at greater risk of getting sick with TB. Health-e News reports that screening people with TB for diabetes is advised in the national guidelines, but does not happen routinely in practice.
According to a 2014 report, diabetes is directly responsible for 15% of all tuberculosis cases worldwide, because it weakens the immune system. “Patients with concurrent diabetes suffer worse tuberculosis treatment outcomes, a higher rate of relapse following tuberculosis treatment, and a higher risk of death from tuberculosis than patients with tuberculosis alone,” noted the authors.
The World Health Organisation (WHO) estimated that in 2015 there were 11% of new TB cases who were living with HIV. Médecins Sans Frontières’ Dr Jenny Hughes, who works with TB patients in Khayelitsha, said that diabetes, in fact, is a higher risk factor for developing TB than even HIV. “Having diabetes increases your risk for TB by at least threefold compared to patients without diabetes. Patients with poorly controlled diabetes or those on insulin are at even higher risk of getting sick with TB,” she said.
But, she said, there is very little data on TB and diabetes from Africa specifically, making the true burden of the co-epidemic in South Africa largely unknown. Hughes said national guidelines stipulate that all TB patients should be screened for diabetes but this is not happening routinely across the country.
Substantial progress has been made in reducing tuberculosis incidence over the past two decades. However, the disease remains a major cause of morbidity and mortality globally. Diabetes is estimated to be the cause of 15% of present tuberculosis cases, mainly because diabetes impairs host defences. Patients with concurrent diabetes suffer worse tuberculosis treatment outcomes, a higher rate of relapse following tuberculosis treatment, and a higher risk of death from tuberculosis than patients with tuberculosis alone. Treatment of patients affected by both diseases can be challenging, particularly in low-income settings. The rapidly increasing prevalence of diabetes—especially in the low-income and middle-income countries where tuberculosis is endemic—is threatening to thwart efforts to tackle tuberculosis over the next two decades. This Series of three papers in The Lancet Diabetes & Endocrinology examines the intersection between tuberculosis and diabetes from several angles, and outlines strategies that will be key to managing and ultimately reducing this dual disease burden.