The association between tuberculosis - TB (a communicable disease) and diabetes (a non-communicable disease) and their synergetic role in causing human suffering has been recognized for centuries but recent studies have undoubtedly established a more direct link between the two. Realizing the gravity of the problem, the WHO issued a policy statement his year, on what needs to be done to address TB-diabetes co-infection. The urgent need to address the comorbidity of these two diseases received serious attention at the recently concluded 43rd Union World Conference on Lung Health in Kuala Lumpur.
In 2011, 8.7 million people fell ill with TB but only 5.8 million or 67% of these were notified to national TB control programmes and 1.4 million died of it. Also, 366 million people were estimated to have diabetes in 2011 but 50% (183 million) of them remained undiagnosed and 4.6 million died due to it. 80% of the people with diabetes live in low and middle income countries and most of them are 40--59 years of age. The number of people with type 2 diabetes is increasing globally and this is likely to complicate TB care and control and vice versa—especially in those high burden countries where the two diseases coexist. Data from recent studies in India reveals that one out of every four persons with TB also has diabetes and one out of every four persons with TB has impaired glucose tolerance. Thus one out of every two persons with TB has either diabetes or high risk of future diabetes and high blood sugar. The national average case detection for TB in India is 107 per 100000, but in case of people with diabetes it goes up to almost 800 per 100000—nearly 8 times more.
Dr Megan Murray of the Harvard School of Public Health informed Citizen News Service - CNS that, “Various studies have already established that diabetes increases the risk of getting TB by 3 times, and this association is mediated by race, ethnicity, age and the severity of diabetes. The risk declines with age (being highest around 20-30 years of age) and increases with hyperglycemia. People with TB and coexisting diabetes are more at risk of death during TB treatment and/or TB relapse after treatment, even when other factors are not taken into account. The chronic inflammatory state of diabetes is very poorly understood. What we know is that in this state the patients’ immune system (both innate and acquired) becomes hyperactive or unregulated. However we still do not know the optimal management strategies and any preventive therapies for people with diabetes at risk for TB.”
Professor Anthony Harries of The International Union Against Tuberculosis and Lung Disease (The Union), reminded us about the similarities between HIV and diabetes linkages to tuberculosis. He said, “Both (HIV and diabetes) increase the risks of (i) getting TB, (ii) poor TB treatment outcomes and (iii) recurrence of TB after getting cured once. All these risks become worse in people living with HIV if their CD4 counts are low and in people living with diabetes if their blood sugar levels are high(hyperglycemia). The linkages between TB and diabetes are compelling; the framework to deal with them is already there and now we just need to have the will and understanding to put it to practice.”
Dr Anil Kapur, President of the World Diabetes Foundation rued that because of the poor knowledge of the links between comorbidity of diabetes and TB, it does not get the desired attention from health professionals, policy makers and the public. In an interview given exclusively to CNS, Dr Kapur said that, “We have known for long about the gravity of the dual problem of TB and diabetes which are occurring in the same environment. But the problem with diabetes is that sometimes it does not produce any immediate dramatic symptoms or end results and so people tend to disregard it and remain complacent about it. Also, in the presence of TB symptoms of the two can be very similar—tiredness, loss of vigor, and a feeling of malaise. The issue is that if you pick up on one of the two diseases you do not focus attention on the other. If you pick TB you ascribe all the symptoms to TB and if you pick diabetes first you ascribe the symptoms to it. We tend to overlook the links and we do not do bidirectional screening for both. So we need to integrate diabetes and TB care at primary care level to ensure that we are able to provide good treatment for not only TB but also for diabetes and other chronic diseases like hypertension. Screening of diabetes patients for TB provides a good opportunity to detect TB cases and thus help in TB treatment care and control.”
“We have these high burden TB countries and high burden diabetes countries—like India and China, and that is where the huge confluence of the two diseases is happening. Unless we deal with it we will be completely swarmed with disastrous consequences. Undiagnosed, inadequately treated and poorly controlled diabetes mellitus is a bigger threat to TB prevention and control in high TB burden countries than we previously realized, and we should not under play or ignore this association. Else we will undo decades of TB control which will prove disastrous, both in terms of loss of lives and economic slowdown.”
The draft 2015--2025 Global Stop TB Strategy of the WHO recognizes the need to address the problem of TB-diabetes co infection. It emphasizes upon the need to-- improve early detection of TB and screen all TB patients for diabetes, just as for HIV; address TB-diabetes comorbidity, caring not only for TB treatment outcomes but also for overall health of the patient; prevent TB by addressing risk factors and improving diabetes control; go outside the health sector to address issues around TB and diabetes through social protection so that there are no financial barriers for people to access healthcare including that for TB and diabetes; and basic science research to understand better the links between these two diseases.
There are many challenges to overcome and it seems to be an uphill task. But then, life is full of challenges and we can overcome them by working together, through mutual responsibility, to rein in this galloping TB-diabetes dual disaster.
(The author is the Managing Editor of Citizen News Service (CNS). She is currently providing on-site news coverage from 43rd Union World Conference on Lung Health, with kind support from the Lilly MDR TB Partnership and Global Alliance for TB Drug Development (TB Alliance). She is a J2J Fellow of National Press Foundation (NPF) USA. She received her editing training in Singapore, has worked earlier with State Planning Institute, UP and taught physics at India's prestigious Loreto Convent. She also authored a book on childhood TB (2012), co-authored a book (translated in three languages) "Voices from the field on childhood pneumonia" and a report on Hepatitis C and HIV treatment access issues in 2011. Email: email@example.com, website: http://www.citizen-news.org)