THE CO-EPIDEMIC OF TB & DIABETES

Presenter Dr M A Bashar Senior Resident

Community MedicinePGIMER,CHD

Tuberculosis and Diabetes:Old Foes

• Indian physician Susruta, in 600 A.D.“phthisis frequently complicated diabetes”

• Autopsy of diabetics in 1883 showed presence of TB granuloma in 50% of diabetics

• Prior to the insulin era: Diagnosis of DM was a death sentence– Leading cause of death was: Tuberculosis

1.Barach JH. Historical facts in Diabetes. Ann Med Hist; 19282.Smurova TF. Lung tuberculosis with associated diabetes mellitus. Excerpta Medico Chest Dis Thorac Surg Tuberc 1980

TB facts• In 2014, 9.6 million people fell ill with TB and 5 million

people died from it, including 0.4 million HIV-positive cases*

• One in three people in the world is infected with latent TB*• Over 95% of TB deaths occur in low and middle-income

countries*• People infected with TB bacteria have a 10% lifetime risk of

falling ill with TB*• However, persons with compromised immune systems,

such as people with HIV, malnutrition or diabetes, or people who use tobacco, have a much higher risk

*who.int/tb/publications/diabetes_tb.pdf

Diabetes fact• About 422 million people worldwide were living with

diabetes in 2014• The global prevalence of diabetes was estimated to be

8.5% among adults aged 18+ years• Diabetes was the direct cause of 1.5 million deaths in 2012• WHO projects that diabetes will be the 7th leading cause

of death in 2030• In 1980, diabetes prevalence was highest in high income

countries, now similar in both high and low income countries

*who.int/tb/publications/diabetes_tb.pdf

Global distribution

80% in LIC and MIC 95% in LIC and MIC

Diabetes and Tuberculosis - the converging pandemics

Risk factors for diabetes and TBWhy the link, when DM is a metabolic disorder and TB is an infectious disease?

• Tobacco smoking and alcoholism may both predispose for diabetes and TB.

DM patients:• Poorly controlled diabetes can lead to increased susceptibility of infection,

such as TB, at a cellular and immunological levels.– DM patients have evidence of impaired cell-mediated immunity, micronutrient

deficiency, pulmonary micro-angiopathy and renal insufficiency, all of which predispose to TB.

TB patients• TB patients have a higher risk of developing diabetes, but it is unclear if TB

can directly cause diabetes → glucose intolerance / diabetes may have been undiagnosed

Public health relevance of the association

• People with diabetes may be more easily infected than non-diabetic people leading to a higher risk of latent TB infection

• According to recent meta-analysis, diabetes patients have three times the risk of contracting TB as non-

diabetics* (95% confidence interval, CI: 2.3–4.3)• TB infection may progress at a faster rate in people with

diabetes than in those without diabetes • Among those with active TB, diabetes may adversely affect TB

treatment outcomes increasing the risk of relapse or death• Diabetes may also accelerate the emergence of drug-resistant

TB, especially multidrug resistant TB• Conversely, TB may trigger the onset of diabetes, and worsen

glycaemic control in existing diabetes

TB is associated with worsening glycaemic control in people with diabetes: - The risk is related to how the blood glucose levels varies, i.e.

uncontrolled diabetes and the length of period of uncontrolled diabetes.

- Higher hyperglycaemia, the higher the risk – for example T1DM patients are likely to be more underweight and typically have uncontrolled diabetes.

Medications for TB may interfere with the treatment of diabetes through drug interactions.

The onset of diabetes may be triggered by TB.

TB infection may progress at a faster rate in people with diabetes than in those without diabetes.

Public health relevance of the association How does TB affect diabetes patients?

• People with diabetes have a 2-3 times higher risk of developing TB disease compared to people without diabetes.

• People with TB and coexisting diabetes have 4 times higher risk of death during TB treatment and higher risk of TB relapse after treatment.

• People with TB and coexisting diabetes are more likely to be sputum positive and take longer to become sputum negative.

• Diabetes may adversely affect TB treatment outcomes by delaying the response time to treatment.

• The emergence of drug-resistant TB may be accelerated by diabetes.

• Diabetes may interfere with the activity of TB medications.

Public health relevance of the associationHow does diabetes affect TB patients?

Challenges of TB control • Over the past two decades, national TB control programmes

worldwide have TB control through DOTS and stop TB strategy with evident success

• Substantial increases in rates of case detection and improved treatment outcomes

• However, improvements are needed to tackle following challenges : First, countries must ensure complete and early case detection of

all types of TB. During 2005–2009, the global TB case detection rate stagnated at

around 60% In many countries, these rates are even lower and long delays in

diagnosis and treatment still occur

Challenges of TB control Second, while globally the treatment success rate has

surpassed 85%,treatment outcomes are suboptimal in many settings and subpopulations;

Third, although rates of incidence, prevalence and death from TB are decreasing globally, the rate of decline is much slower than forecast leading to missing of MDG goal of halving TB prevalence and TB death rates in some of the WHO regions;

Additional efforts of prevention by intervening on known social determinants and risk factors of TB, such as HIV/AIDS, smoking, malnutrition, alcohol dependency, diabetes, crowded living conditions, and indoor air pollution is required

Epidemiological results from International Projects

• TB patients screened for diabetes– In India, results have shown that prevalence of diabetes among TB patients

ranges between 13-25%, the highest being the particularly in the South → this fits well the 3-fold risk (World Diabetes Foundation(WDF) 08-385 & 10-585).

– In China results have shown that the prevalence of diabetes among TB patients has shown to be 12.4% (WDF10-585)

• Diabetes patients screened for TB:– In India, results have shown that the incidence rate of TB among diabetes

patients was almost 8 timer higher, as compared to TB cases in general population (WDF10-585).

– In China results have shown that the that the incidence rate of TB among diabetes patients was almost 5.5 timer higher, as compared to TB cases in general population(WDF10-585).

Prevalence rates dependant on two major factors: Prevalence rate in population and the screening methodology (RBG, FBG or OGTT).

TB & Diabetes co-epidemic situation in Indian

• In India, in 2011, there were 61.3 million people living with diabetes, and 983,000 deaths from the disease.

• India accounts for one-fifth of the incidence of TB cases and ranks one among the 22 high burden countries, which are contributing to 80% of global TB burden

• It has 1.98 million people developing TB and almost 300,000 people dying of it each year

• According to Stevenson et al. nearly 15% of TB burden in India in the year 2000 was attributed to diabetes whereas HIV accounted for 3.4% of TB cases

Collaborative framework for care and control oftuberculosis and diabetes

The Framework• A joint document by WHO and International Union against

TB & Lung diseases, released in year 2011• The framework aims to guide national programmes,

clinicians and others engaged in care of patients on establishing coordinated response to both diseases, at organizational and clinical levels

• Framework is based on evidence collated from systematic reviews and existing guidelines on the diagnosis and management of TB and diabetes

• In order fill the knowledge gaps, the framework includes a list of priority research areas.

The three areas of recommendations

http://www.who.int/tb/publications/2011/en/index.html Document available at:

Recommendations • Establish mechanisms for collaboration1. Joint coordination at regional, district and/or local levels

(sensitive to country-specific factors), with representation from all relevant stakeholders

2. Surveillance of TB among diabetes patients in settings with medium to high burdens of TB

3. Surveillance of diabetes among TB patients in all countries4. National programmes should agree a core set of indicators

and tools to collect data for monitoring and evaluating activities to improve care and prevention of both diseases

Recommendations • Detect and manage TB in patients with diabetes5. At a minimum, people with diabetes should be screened for chronic

cough (that is, cough lasting more than 2 weeks) at the time of their diagnosis with diabetes and, if possible, during regular check-ups.

6. Screening for TB diseases on broader indications (for example, for all people in whom diabetes is diagnosed, regardless of symptoms) should be explored as part of the research agenda to improve the diagnosis of TB among people with diabetes

7. A referral system should be established so that patients suspected of having TB are promptly referred to TB diagnostic and treatment centres, and evaluated in accordance with guidelines of the national TB control

Recommendations 8. Case-finding for TB should be intensified by increasing

awareness of and knowledge about the interactions between diabetes and TB, among health-care workers and the populations they serve

9. Health-care facilities, including diabetes clinics, should have in place an infection control plan that includes administrative and environmental control measures to reduce transmission of TB within health-care settings.

10. Treatment and case management of TB in people with diabetes should be provided in accordance with existing TB treatment guidelines and international standards.

Recommendations • Detect and manage diabetes in patients with TB11. Patients with TB should be screened for diabetes at the start

of their treatment, where resources for diagnosis are available12. Management of diabetes in TB patients should be provided

in line with existing management guidelines.

Thanks