Diabetes triples the risk of developing tuberculosis (TB). Consequently, rates of TB are higher in people with diabetes than in the general population, and diabetes is a common comorbidity in people with TB. Diabetes can worsen the clinical course of TB, and TB can worsen glycaemic control in people with diabetes. Individuals with both conditions thus require careful clinical management. Strategies are needed to ensure that optimal care is provided to patients with both diseases: TB must be diagnosed early in people with diabetes, and diabetes must be diagnosed early in people with TB.

Changes in lifestyle and diet have contributed to an increased prevalence of diabetes in many low-income and middle-income countries where the burden of TB is high. The growing burden of diabetes is contributing to sustained high levels of TB in the community, and the proportion of TB cases attributable to diabetes globally is likely to increase over time. This double burden of disease is a serious and growing challenge for health systems.

Given the absence of international guidelines on the joint management and control of TB and diabetes, the World Health Organization (WHO) and the International Union Against Tuberculosis and Lung Disease (the Union) identified key questions to be answered and commissioned systematic reviews of studies addressing those questions. A series of expert consultations were organized to assess the findings of the systematic reviews and a guideline group was established to develop this provisional collaborative framework.

The framework aims to guide national programmes, clinicians and others engaged in care of patients and prevention and control of diabetes and TB on how to establish a coordinated response to both diseases, at organizational and clinical levels. The framework is based on evidence collated from systematic reviews and existing guidelines on the diagnosis and management of TB and diabetes. The systematic reviews confirmed the weak evidence base for the effectiveness and cost-effectiveness of collaborative interventions. The framework is therefore provisional; several of its recommendations are provisional pending better evidence. In order to provide advice on how to fill the knowledge gaps, the framework includes a list of priority research areas.

The framework includes the following provisional recommendations:

Establish mechanisms for collaboration

1. Joint coordination should be established at regional, district and/or local levels (sensitive to country-specific factors), with representation from all relevant stakeholders. A joint plan for activities should be drawn up and reflected in national plans for noncommunicable diseases and TB.
2. Surveillance of TB should be initiated among diabetes patients in settings with medium to high burdens of TB.
3. Surveillance of diabetes should be initiated among TB patients in all countries.
4. Where collaborative activities are being established, 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. Diabetes programmes should explore the possibility of adapting the DOTS system to monitor and report diabetes cases and treatment outcomes.

Detect and manage TB in patients with diabetes

5.

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. Those with positive TB symptoms should be examined as per national guidelines. Other diagnostic procedures (for example, for extrapulmonary TB) should also be pursued rigorously as per national guidelines.

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 programme.

8.

Case-finding for TB should be intensified by increasing awareness of and knowledge about the interactions between diabetes and TB, including joint risk factors, 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. These measures should adhere to WHO's international guidelines for TB infection control.

10.

Treatment and case management of TB in people with diabetes should be provided in accordance with existing TB treatment guidelines and international standards. The same TB treatment regimen should be prescribed for people with diabetes as for people without diabetes.

Detect and manage diabetes in patients with TB

11.

Patients with TB should be screened for diabetes at the start of their treatment, where resources for diagnosis are available. The type of screening and diagnostic tests should be adapted to the context of local health systems and the availability of resources, while awaiting additional evidence on the best screening and diagnostic approach or approaches.

12.

Management of diabetes in TB patients should be provided in line with existing management guidelines.