Tuberculosis and diabetes in low and moderate tuberculosis incidence countries

Glycemic control during TB treatment among Filipinos: The Starting Anti-Tuberculosis Treatment Cohort Study

Poor TB treatment outcomes are observed in patients with type 2 diabetes mellitus (DM) comorbidity and glycemic control throughout treatment may play a role. The objective of this study was to investigate glycemic control longitudinally among Filipino adults undergoing TB treatment using mixed-effects linear and logistic regression. Analyses were conducted in 188 DM-TB patients out of 901 enrolled in the Starting Anti-TB Treatment (St-ATT) cohort, with a median baseline glycosylated hemoglobin (HbA1c) of 8.2% (range 4.5-13.3%). Previous versus new DM diagnosis was associated with higher mean HbA1c (worse glycemic control) during treatment, with a smaller effect amongst those with central obesity (coefficient 0.80, 95% confidence interval [CI] 0.26, 1.57, P = 0.043) than amongst those without central obesity (coefficient 3.48, 95% CI 2.16, 4.80, P<0.001). In those with a new DM diagnosis, central obesity was associated with higher blood glucose (coefficient 1.62, 95% CI 0.72, 2.53, P = 0.009). Of 177 participants with ≥2 HbA1c results, 40% had uncontrolled glycemia (≥2 HbA1c results ≥8%). Of 165 participants with ≥3 HbA1c results, 29.9% had consistently-controlled glycemia, 15.3% had initially-uncontrolled glycemia, and 18.6% had consistently-uncontrolled glycemia. Previous versus new DM diagnosis and glucose-lowering medication use versus no use were associated with having uncontrolled versus controlled glycemia (adjusted odds ratio [aOR] 2.50 95%CI 1.61, 6.05, P = 0.042; aOR 4.78 95% CI 1.61,14.23, P<0.001) and more likely to have consistently-uncontrolled versus consistently-controlled glycemia (adjusted relative risk ratio [aRRR] 5.14 95% CI 1.37, 19.20, P = 0.015; aRRR 10.24 95% CI 0.07, 0.95, P = 0.003). Relapse cases of TB were less likely than new cases to have uncontrolled (aOR 0.20 95%CI 0.06, 0.63, P = 0.031) or consistently-uncontrolled (aRRR 0.25 95%CI 0.07, 0.95, P = 0.042) versus controlled glycemia. Those with long-term DM, suggested by previous diagnosis, glucose-lowering medication use and possibly central obesity, may require additional support to manage blood glucose during TB treatment.

Assessment of Comorbidity in Patients with Drug-Resistant Tuberculosis

A wide range of comorbidities, especially in multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) patients, markedly complicates selecting effective treatment of tuberculosis (TB) and preventing the development of adverse events. At present, it is impossible to assess the severity of comorbid pathologies and develop indications for the administration of accompanying therapy in TB patients. The aim of this study was to identify the difference in the range of comorbidities between patients with MDR-TB and XDR-TB and assess the impact of comorbidities on TB treatment. Materials and Methods: A retrospective, prospective study was conducted where 307 patients with MDR-TB and XDR-TB pulmonary tuberculosis aged 18 to 75 years who received eTB treatment from 2016 to 2021 in St. Petersburg hospitals were analyzed. The analysis showed that the comorbidity level in MDR-TB and XDR-TB patients with TB treatment success and treatment failure was comparable with the use of the Charlson Comorbidity Index (CCI). The CCI demonstrated declining data in terms of TB treatment outcome period in both groups. A slight predominance of CCI score (3 to 4 points) in XDR-TB (22.7%) vs. MDR-TB (15.4%) patients was found. In the case of an TB treatment failure, the CCI level in MDR-TB vs. XDR-TB patients was characterized by a significantly higher rate of low magnitude (ranging from 1 to 2 points) in 21.1% vs. 4.5% (p < 0.05), which was higher in XDR-TB patients (ranging from 4 to 5 points, in 10.0% vs. 0, χ2 = 33.7 (p < 0.01)). Chronic viral hepatitis B and C infection, cardiovascular pathology, chronic obstructive pulmonary disease, and chronic alcoholism were found to be significant comorbidity factors that influenced the TB treatment success. Conclusions: It is evident that XDR-TB patients comprise a cohort with the most severe disease course due to comorbidities impacting TB treatment efficacy. The obtained data pointed to the need to determine comorbidity severity in patients with drug-resistant Mbt prior to administering TB treatment schemes.

How can tuberculosis services better support patients with a diabetes co-morbidity? A mixed methods study in the Philippines

BACKGROUND

People with diabetes mellitus (DM) have an estimated two- to three-times greater risk of adverse tuberculosis (TB) treatment outcomes compared to those without DM. Blood glucose control is a primary aim of managing DM during TB treatment, yet TB programmes are not generally adapted to provide DM services. The purpose of this study was to understand perceptions and the lived experiences of diabetic patients in TB treatment in the Philippines, with a view to informing the development of disease co-management strategies.

METHODS

This mixed methods study was conducted within a prospective cohort of adults newly-starting treatment for drug-sensitive and drug-resistant TB at 13 public TB clinics in three regions of the Philippines. Within the subset of 189 diabetic persons who self-reported a prior DM diagnosis, or were diagnosed by screenings conducted through the TB clinic, longitudinal blood glucose data were used to ascertain individuals' glycaemic control (controlled or uncontrolled). Univariable logistic regression analyses exploring associations between uncontrolled glycaemia and demographic and clinical factors informed purposive sampling of 31 people to participate in semi-structured interviews. All audio-recorded data were transcribed and thematic analysis performed.

RESULTS

Participants - both with controlled and uncontrolled blood glucose - were knowledgeable about diabetes and its management. However, a minority of participants were aware of the impact of DM on TB treatment and outcomes. Many participants newly-diagnosed with DM at enrolment in TB treatment had not perceived any diabetic symptoms prior and would have likely not sought clinical consult otherwise. Access to free glucose-lowering medications through TB clinics was a key enabling resource. However, participants expressed fear of side effects and interrupted access to glucose-lowering medications, and a preference for phytotherapy. Many participants felt that physical and financial impacts of TB and its treatment were challenges to DM management.

CONCLUSIONS AND RECOMMENDATIONS

Results of this study indicate that public TB clinics can provide diabetic patients with additional health care resources and education to address co-morbidity. TB programmes might consider identifying patients with complicated DM, and offering diabetic monitoring and management, as DM and diabetic complications may compound the burden of TB and its treatment.

Tuberculosis and diabetes: increased hospitalisations and mortality associated with renal impairment

BACKGROUND

Diabetes mellitus (DM) triples a person's risk of active tuberculosis (TB) and is associated with increased mortality. It is unclear whether diabetes status and/or the associated renal dysfunction is associated with poor TB outcomes in New Zealand, which has high diabetes screening.

AIM

To characterise the population of TB-DM and TB-alone to assess the effect of diabetes status and renal function on hospitalisation and mortality.

METHODS

Clinical records from all adult patients diagnosed with TB in Auckland over a 6-year period (2010-2015) were reviewed. Baseline demographics, clinical presentation and microbiological data were assessed to compare the rates of hospitalisation and mortality between those with TB-DM and TB-alone. Statistical significance was defined as P < 0.05.

RESULTS

A total of 701 patients was identified with TB; 120 (17%) had an unknown diabetes status and were excluded, and 135 had co-existing diabetes. The TB-DM and TB-alone groups had similar distribution of TB site and proportions of Mycobacterium tuberculosis culture positivity. Univariate analysis showed TB-DM patients had statistically significantly higher proportions of acute hospitalisation and mortality. Multivariate logistic regression showed only a reduced estimated glomerular filtration rate (eGFR) accounted for the higher rates of hospitalisation, with the odds of hospitalisation increasing by 2% for every unit decrease in eGFR. The odds of mortality increased by 6% for every year increase in age, and the odds of mortality increased by 3% for every unit reduction in eGFR.

CONCLUSIONS

Diabetes is associated with higher TB hospitalisation and mortality; however, this is likely mediated by increased age and chronic kidney disease.

Immunologic, metabolic and genetic impact of diabetes on tuberculosis susceptibility

Due to the increasing prevalence of diabetes mellitus (DM) globally, the interaction between DM and major global diseases like tuberculosis (TB) is of great public health significance, with evidence of DM having about a three-fold risk for TB disease. TB defense may be impacted by diabetes-related effects on immunity, metabolism, and gene transcription. An update on the epidemiological aspects of DM and TB, and the recent trends in understanding the DM-associated immunologic, metabolic, and genetic mechanisms of susceptibility to TB will be discussed in this review. This review highlights gaps in the incomplete understanding of the mechanisms that may relate to TB susceptibility in type 2 DM (T2DM). Understanding these three main domains regarding mechanisms of TB susceptibility in T2DM patients can help us build practical treatment plans to lessen the combined burden of the diseases in rampant areas.

Prediabetes and risk of active tuberculosis: a cohort study from Northern Taiwan

Background

Diabetes mellitus (DM) is a well-established risk factor for active tuberculosis (TB) infection. Despite the worldwide rapid increase in the prevalence of prediabetes, its impact on the risk of active TB remains largely unknown. This study aimed to investigate the relationship between prediabetes and risk of active TB in a large cohort study.

Methods

A total of 119 352 participants were screened from a community-based health screening programme in Northern Taiwan. Diabetes mellitus and prediabetes were defined by baseline fasting plasma glucose (FPG) and prescription of anti-diabetic drugs. Incident cases of active TB were identified from the National Tuberculosis Registry. Kaplan–Meier curves and Cox regression analysis were employed to estimate the hazard ratios for prediabetes and DM compared with normoglycaemia. Spline regression was performed to investigate the dose-response relationship between FPG level and risk of TB disease.

Results

At baseline, 27 404 (22.96%) participants had prediabetes and 10 943 (9.17%) participants had DM. After an average follow-up of 7.2 years, 322 TB cases occurred. The adjusted hazard ratio of developing active TB disease was 0.73 [95% confidence interval (CI) 0.55–0.97] for prediabetic and 1.48 (95% CI 1.11–1.98) for diabetic participants compared with normoglycaemic individuals. Spline regression revealed a U-shaped association between FPG level and risk of active TB disease, with the lowest risk at FPG around110 mg/dl. Sensitivity analyses were conducted to exclude factors such as potential confounders (including body mass index), misclassification of glycaemic level, and selection bias, and results showed that those factors could not explain the lower risk of active TB.

Conclusions

Prediabetes was associated with a 27% reduced risk of active TB disease compared with normoglycaemia. The biological mechanism of this inverse association and its implication for global nutrition transition and TB control should be further investigated.

Screening of latent tuberculosis infection among patients with diabetes mellitus from a high-burden area in Brazil

Although several cohort studies have raised the important association between diabetes mellitus (DM) and latent tuberculosis infection (LTBI), evidences are limited and controversial. Furthermore, it is well documented that the poor glycemic control may exacerbate the risk for active TB. Thus, the monitoring of diabetic patients living in high-incidence areas for TB is an important concern in views of available diagnostic tests for LTBI. In this cross-sectional study, we estimate the association of DM and LTBI among diabetic patients classified as type-1 DM (T1D) or type-2 DM (T2D) living in Rio de Janeiro, RJ, Brazil - considered a high TB burden region of these country. Non-DM volunteers were included as endemic area healthy controls. All participants were screened for DM using glycosylated-hemoglobin (HbA_1c) and for LTBI using the QuantiFERON-TB Gold in Tube (QFT-GIT). Demographic, socioeconomic, clinical and laboratorial data were also assessed. Among 553 included participants, 88 (15.9%) had QFT-GIT positive test, of which 18 (20.5%) were non-DM, 30 (34.1%) T1D and 40 (45.4%) T2D. After adjustments for potential baseline confounders, age, self-reported non-white skin color and an active TB case in the family were significantly associated with LTBI among the studied population by using a hierarchical multivariate logistic regression analysis. Additionally, we verified that T2D patients were able to produce significant increased interferon-gamma (IFN-γ) plasma levels in response to Mycobacterium tuberculosis-specific antigens, when compared to non-DM individuals. Altogether, our data showed an increased prevalence of LTBI among DM patients, albeit non-statistically significant, and point out to important independent factors associated with LTBI, which deserve attention in monitoring patients with DM. Moreover, QFT-GIT test seems to be a good tool to screening LTBI in this population, even in a high TB burden area.

Subjects With Diabetes Mellitus Are at Increased Risk for Developing Tuberculosis: A Cohort Study in an Inner-City District of Barcelona (Spain)

Background

Tuberculosis is the leading cause of mortality from lung infectious disease worldwide in recent years, and its incidence has re-emerged in large cities in low-incidence countries due to migration and socioeconomic deprivation causes. Diabetes mellitus and tuberculosis are syndemic diseases, with diabetes being considered a risk factor for developing tuberculosis.

Objective

To investigate whether diabetic patients were at increased risk of tuberculosis living in an inner-district of a large city of northeastern Spain.

Methods

Observational matched retrospective cohort study based on clinical records from the population of the lowest socioeconomic status in Barcelona (Ciutat Vella district). A cohort including patients with type 1 and type 2 diabetes mellitus in 2007 and new cases until 2016 (8004 subjects), matched 1:1 by sex and age with a non-diabetic cohort. Follow-up period was until December 31st 2018. We evaluated the risk of developing tuberculosis in diabetic patients compared to non-diabetic patients during the follow up period. We used time-to-event analysis to estimate the incidence of tuberculosis, and competing risks regression by clusters and conditional Cox regression models to calculate the hazard ratio (HR) and its 95% confidence intervals (CI).

Results

Among the 16,008 included subjects, the median follow-up was 8.7 years. The mean age was 57.7 years; 61.2% men and 38.8% women in both groups. The incidence of tuberculosis was 69.9 per 100,000 person-years in diabetic patients, and 40.9 per 100,000 person-years in non-diabetic patients (HR = 1.90; CI: 1.18-3.07). After adjustment for the country of origin, chronic kidney disease, number of medical appointments, BMI, alcoholism and smoking, the risk remained higher in diabetic patients (1.66: CI 0.99-2.77). Additionally, subjects from Hindustan or with a history of alcohol abuse also showed a higher risk of developing tuberculosis (HR = 3.51; CI:1.87-6.57, and HR = 2.73; CI:1.22-6.12 respectively).

Conclusion

People with diabetes mellitus were at higher risk of developing tuberculosis in a large cohort recruited in an inner-city district with a high incidence for this outcome, and low socioeconomic conditions and high proportion of migrants. This risk was higher among Hindustan born and alcohol abusers.

Increased Risk of Incident Diabetes Among Individuals With Latent Tuberculosis Infection

OBJECTIVE

In cross-sectional U.S. studies, patients with diabetes had twice the prevalence of latent tuberculosis infection (LTBI) compared with those without diabetes. However, whether LTBI contributes to diabetes risk is unknown. We used longitudinal data to determine if LTBI is associated with increased diabetes incidence.

RESEARCH DESIGN AND METHODS

We conducted a retrospective cohort study among U.S. Veterans receiving care in the Veterans Health Administration from 2000 to 2015. Eligibility included all patients without preexisting diabetes who received a tuberculin skin test (TST) or interferon-γ release assay (IGRA). We excluded patients with a history of active TB and those diagnosed with diabetes before or within 2 years after LTBI testing. Patients were followed until diabetes diagnosis, death, or 2015. LTBI was defined as TST or IGRA positive. Incident diabetes was defined by use of ICD-9 codes in combination with a diabetes drug prescription.

RESULTS

Among 574,113 eligible patients, 5.3% received both TST/IGRA, 79.1% received TST only, and 15.6% received IGRA only. Overall, 6.6% had LTBI, and there were 2,535,149 person-years (PY) of follow-up after LTBI testing (median 3.2 years). The diabetes incidence rate (per 100,000 PY) was greater in patients with LTBI compared with those without (1,012 vs. 744; hazard ratio [HR] 1.4 [95% CI 1.3-1.4]). Increased diabetes incidence persisted after adjustment for covariates (adjusted HR [aHR] 1.2 [95% CI 1.2-1.3]) compared with those without LTBI. Among patients with LTBI, diabetes incidence was similar in those treated for LTBI compared with those who were not treated (aHR 1.0 [95% CI 0.9-1.1]).

CONCLUSIONS

Comprehensive longitudinal data indicate that LTBI is associated with increased diabetes incidence. These results have implications for people with LTBI, ∼25% of the global population.

Diabetes-Associated Susceptibility to Tuberculosis: Contribution of Hyperglycemia vs. Dyslipidemia

Diabetes is a major risk factor for tuberculosis (TB). Diabetes increases the risk of the progression from latent tuberculosis infection (LTBI) to active pulmonary TB and TB patients with diabetes are at greater risk of more severe disease and adverse TB treatment outcomes compared to TB patients without co-morbidities. Diabetes is a complex disease, characterised not only by hyperglycemia but also by various forms of dyslipidemia. However, the relative contribution of these underlying metabolic factors to increased susceptibility to TB are poorly understood. This review summarises our current knowledge on the epidemiology and clinical manifestation of TB and diabetes comorbidity. We subsequently dissect the relative contributions of body mass index, hyperglycemia, elevated cholesterol and triglycerides on TB disease severity and treatment outcomes. Lastly, we discuss the impact of selected glucose and cholesterol-lowering treatments frequently used in the management of diabetes on TB treatment outcomes.

Cost-Effectiveness Analysis of High-Risk Groups Tuberculosis Screening in Malaysia

Screening of high-risk groups for Tuberculosis (TB) is considered as the cornerstone for TB elimination but the measure of cost-effectiveness is also crucial in deciding the strategy for TB screening. This study aims to measure the cost-effectiveness of TB screening between the various high-risk groups in Malaysia. A decision tree model was developed to assess the cost-effectiveness of TB screening among the high-risk groups from a provider perspective using secondary data from the year 2016 to 2018. The results are presented in terms of an Incremental Cost-Effectiveness Ratio (ICER), expressed as cost per TB case detected. Deterministic and Probabilistic Sensitivity Analysis was also performed to measure the robustness of the model. TB screening among Person Living with Human Immunodeficiency Virus (PL HIV) was the most cost-effective strategy, with MYR 2,597.00 per TB case detected. This was followed by elderly, prisoners and smokers with MYR 2,868.62, MYR 3,065.24, and MYR 4,327.76 per one TB case detected, respectively. There was an incremental cost of MYR 2.49 per screening, and 3.4 TB case detection per 1,000 screening for TB screening among PL HIV in relation to TB screening among prisoners. The probability of symptomatic cases diagnosed as TB was the key driver for increasing cost-effectiveness efficacy among PL HIV. Results of the study suggest prioritization of high-risk group TB screening program by focusing on the most cost-effective strategy such as screening among PL HIV, prisoners and elderly, which has a lower cost per TB case detected.

Association amid the comorbidity of Diabetes Mellitus in patients of Active Tuberculosis in Pakistan: A matched case control study

Objectives:

This study aims to test the association between diabetes and tuberculosis.

Methods:

It is a matched case control study conducted in tertiary care hospitals in 2019-2020. Cases and controls were 144 each, selected on the basis of an odds ratio of 2 at 95% confidence interval with a significance level of 5%. Cases of pulmonary tuberculosis were selected through consecutive sampling technique, either visiting OPD or admitted in hospital. Controls were taken from the general population and frequency matching was done based on age, gender and socioeconomic status. Data was collected through structured questionnaire after taking written consent. Data was analyzed on SPSS version 23. Binary Logistic regression model was applied for finding association between the risk factors and the disease. P value <0.05 was considered statistically significant.

Results:

Out of all cases and controls, 45% and 20% were diabetics respectively. The association between the risk factors and tuberculosis was estimated by univariate analysis, positive association was found between diabetes and tuberculosis (OR= 3.32), a high frequency of diabetes in cases as compared to controls were observed with a highly significant p- value (<.001).

Conclusions:

This study provides evidence for a strong positive association between tuberculosis and diabetes.

Metformin enhances protection in guinea pigs chronically infected with Mycobacterium tuberculosis

Tuberculosis (TB) is a chronic inflammatory disease that is often associated with alterations in systemic and cellular metabolism that resolves following successful antimicrobial drug treatment. We hypothesized that altered systemic glucose metabolism as a consequence of Mycobacterium tuberculosis (Mtb) infection, contributes to TB pathogenesis, and when normalized with anti-glycemic drugs would improve clinical outcomes. To test this hypothesis, guinea pigs were treated daily with the anti-diabetic drug metformin starting 4 weeks prior or concurrent with aerosol exposure to the H37Rv strain of Mtb. In the chronic stages of infection, Mtb infected metformin-treated animals had restored systemic insulin sensitivity but remained glucose intolerant as determined by oral glucose tolerance testing. Despite persistent glucose intolerance, metformin-treated guinea pigs had a 2.8-fold reduction in lung lesion burden and a 0.7 log decrease in CFUs. An alternative hypothesis that metformin treatment improved clinical disease by having a direct effect on immune cell energy metabolism was tested using extracellular flux analysis and flow cytometry. The proinflammatory immune response to Mtb infection in untreated guinea pigs was associated with a marked increase in energy metabolism (glycolysis and mitochondrial respiration) of peripheral blood mononuclear cells (PBMCs), which was normalized in metformin-treated guinea pigs. Moreover, both CD4⁺ and CD8⁺ T lymphocytes from Mtb infected, metformin treated animals maintained a more normal mitochondrial membrane potential while those isolated from untreated animals had persistent mitochondrial hyperpolarization. These data suggest that metformin promotes natural host resistance to Mtb infection by maintaining immune cell metabolic homeostasis and function during the chronic stages of active TB disease.

Tuberculosis treatment outcomes of notified cases: trends and determinants of potential unfavourable outcome, France, 2008 to 2014

BackgroundSurveillance of tuberculosis (TB) treatment outcome, for which reporting has been mandatory in France since 2007, is a key component of TB control.AimWe aimed to present surveillance data for non-multidrug-resistant (MDR) cases reported between 2008 and 2014, and identify factors associated with potentially unfavourable treatment outcome.MethodsPatients were classified according to their treatment outcome 12 months after beginning treatment. Poisson regression with a robust error variance was used to investigate factors associated with potentially unfavourable treatment outcome. Missing data were handled using multiple imputation.ResultsA total of 22,526 cases were analysed for treatment outcome. Information available on treatment outcome increased between 2008 (60%) and 2014 (71%) (p < 0.001). During this period, 74.1% of cases completed treatment, increasing from 73.0% in 2008 to 76.9% in 2014 (p < 0.001). This proportion was 74.0% in culture-positive pulmonary cases. Overall, 19.8% of cases had a potentially unfavourable outcome, including lost-to-follow-up, transferred out, still on treatment, death related to TB and interrupted treatment. Potentially unfavourable outcome was significantly associated with TB severity, residing in congregate settings, homelessness, being a smear-positive pulmonary case, being born abroad and residing in France for < 2 years, history of previous anti-TB treatment and age > 85 years.ConclusionMonitoring of treatment outcome is improving over time. The increase in treatment completion over time suggests improved case management. However, treatment outcome monitoring needs to be strengthened in cases belonging to population groups where the percentage of unfavourable outcome is the highest and in cases where surveillance data shows poorer documented follow-up.

Aspirin enhances the clinical efficacy of anti-tuberculosis therapy in pulmonary tuberculosis in patients with type 2 diabetes mellitus

Background: Tuberculosis in patients with diabetes mellitus is characterised by rapid disease progression, poor treatment efficacy, poor prognosis and poses a new challenge in tuberculosis treatment and control.Methods: Patients with pulmonary TB and type 2 DM were recruited at Yijishan Hospital of Wannan Medical College. A total of 348 patients were randomly assigned to two groups. The aspirin group (aspirin + TB/DM) included 174 patients who received anti-TB therapy and enteric-coated aspirin tablets (100 mg/tablet). The control group (placebo + TB/DM) included 174 patients who received anti-TB therapy and enteric-coated placebo tablets (an identical tablet containing no drug). Eighty-two patients in the aspirin group and 86 in the control group completed the trial and were included in the analysis. Clinical characteristics, laboratory test results, imaging data and side effects of aspirin were monitored.Results: Aspirin treatment affect certain signs and symptoms. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were lower in the aspirin group than in the control group after treatment (Both p = .000). The sputum-negative conversion rate was 86.7% in the aspirin group, significantly higher than in the control group (53.8%) (p = .031). After two months of treatment, the differences in the number of cases with cavities, the number of cavities, and maximum diameter of cavities in the aspirin group were statistically significant (p = .003, p = .023 and p = .015 respectively).Conclusion: Our findings suggest that aspirin may improve treatment in patients with pulmonary TB and type 2 DM.

Screening for pulmonary tuberculosis in high-risk groups of diabetic patients

BACKGROUND

The double burden of diabetes mellitus (DM) and tuberculosis (TB) has attracted increasing attention, because DM not only increases the risk of active TB but also affects treatment outcomes. Screening for TB among diabetic patients has been recommended, but requires real-world evidence by considering its cost-effectiveness, cost-utility ratio, and cost-benefit ratio.

METHODS

A screening program was conducted in Jiangyin City of Jiangsu Province, China. A total of 14 869 diabetic patients received regular physical examinations for three consecutive years and were followed for the diagnosis of TB. The cost of screening and the effectiveness, utility, and social benefits attributed to the program were evaluated. In addition, a matched case-control study was conducted and the nomogram was used to identify high-risk groups that could be the target population for screening.

RESULTS

Among the 14 869 diabetic patients who participated in this screening program, 22 were diagnosed with TB, resulting in an incremental cost-effectiveness ratio (ICER) of 83 910 CNY per disability-adjusted life-year (DALY) gained and a cost-benefit ratio of 0.50. If the screening program was limited to high-risk diabetic patients by considering body mass index (BMI), fasting blood glucose (FBG), and triglycerides, the ICER decreased to 34 303 CNY per DALY gained and the cost-benefit ratio increased to 1.22.

CONCLUSIONS

Screening for TB using regular chest X-ray examinations is feasible but not economical in areas with a low incidence of TB. It is recommended that diabetic patients with a low BMI, high FBG, and low triglycerides are selected as subjects for TB screening.

Pulmonary tuberculous cavities in diabetic patients: Glycemic control is still the dominant factor despite the emerging role of metformin

BACKGROUND

Previous studies have reported an increased risk of cavities in diabetic patients with pulmonary tuberculosis (PTB), which may be associated with poor glycemic control. Cavities have a negative impact on PTB treatment outcomes; however, the possible interaction of other potentially confounding diabetes-related variables regarding pulmonary cavities have not been fully evaluated.

METHODS

We conducted a retrospective cohort study of diabetic patients with culture-proven PTB. The patients' chest X-rays (CXRs) and computed tomography (CT) scans were reviewed to assess the effects of clinical factors, glycosylated hemoglobin (HbA1c) levels, and antidiabetic agents on cavitary lesions.

RESULTS

Among 128 diabetic PTB patients, those with pulmonary cavities on CXRs and CT scans presented younger ages, lack of metformin treatment, and significantly higher HbA1c levels than those without cavities. Multivariate logistic regression analysis revealed significantly higher HbA1c levels in patients with cavities than in those without cavities on CXRs (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.12-1.61) and CT scans (OR, 1.36; 95% CI, 1.13-1.64). Patients with multiple cavities had significantly higher HbA1c levels than those with a single cavity on CT scans (p = 0.002). No significant differences in other variables, including metformin treatment, were noted between the groups.

CONCLUSION

This study suggests that despite multiple potential confounding variables, including metformin use, poor glycemic control is still the dominant risk factor for cavitary lesions in diabetic patients with PTB. Efforts to improve glycemic control in diabetic PTB patients may be of considerable value in facilitating antimycobacterial treatment.

Diabetes in developing countries

There has been a rapid escalation of type 2 diabetes (T2D) in developing countries, with varied prevalence according to rural vs urban habitat and degree of urbanization. Some ethnic groups (eg, South Asians, other Asians, and Africans), develop diabetes a decade earlier and at a lower body mass index than Whites, have prominent abdominal obesity, and accelerated the conversion from prediabetes to diabetes. The burden of complications, both macro- and microvascular, is substantial, but also varies according to populations. The syndemics of diabetes with HIV or tuberculosis are prevalent in many developing countries and predispose to each other. Screening for diabetes in large populations living in diverse habitats may not be cost-effective, but targeted high-risk screening may have a place. The cost of diagnostic tests and scarcity of health manpower pose substantial hurdles in the diagnosis and monitoring of patients. Efforts for prevention remain rudimentary in most developing countries. The quality of care is largely poor; hence, a substantial number of patients do not achieve treatment goals. This is further amplified by a delay in seeking treatment, "fatalistic attitudes", high cost and non-availability of drugs and insulins. To counter these numerous challenges, a renewed political commitment and mandate for health promotion and disease prevention are urgently needed. Several low-cost innovative approaches have been trialed with encouraging outcomes, including training and deployment of non-medical allied health professionals and the use of mobile phones and telemedicine to deliver simple health messages for the prevention and management of T2D.

Coprevalence of type 2 diabetes mellitus and tuberculosis in low-income and middle-income countries: A systematic review

Increasing coprevalence of diabetes mellitus (DM) and tuberculosis (TB) in low-income and middle-income countries (LMICs) indicates a rising threat to the decades of progress made against TB and requires global attention. This systematic review provides a summary of type 2 diabetes and tuberculosis coprevalence in various LMICs. We searched PubMed, Ovid Medline, Embase, and PsychINFO databases for studies that provided estimates of TB-DM coprevalence in LMICs published between 1990 and 2016. Studies that were non-English and exclusively conducted in multidrug resistant-tuberculosis or type 1 diabetes and inpatient settings were excluded. We reviewed 84 studies from 31 countries. There were huge diversity of study designs and diagnostic methods used to estimate coprevalence, and this precluded pooling of the results. Most studies (n = 78) were from small, localized settings. The DM prevalence among TB patients in various LMICs varied from 1.8% to 45%, with the majority (n = 44) between 10% and 30%. The TB prevalence among people with DM ranged from 0.1% to 6.0% with most studies (n = 9) reporting prevalences less than 2%. Coprevalence of TB-DM was higher than general population prevalence of either diseases in these countries. This study underscores the need for intervention and more focused research on TB DM bidirectional screening programs in low-income and middle-income countries as well as integrated chronic disease management.

Impact of Diabetes Mellitus on the Presentation and Response to Treatment of Adults With Pulmonary Tuberculosis in Qatar

Background

Persons with diabetes mellitus (DM) have a 3-fold increased risk of tuberculosis (TB). Atypical radiographic findings and differences in bacteriologic response during anti-TB treatment have been reported in earlier studies; however, the findings have varied. We evaluated the effect of DM on manifestations and response to treatment in adults with pulmonary TB in Qatar.

Methods

The impact of DM on the clinical and radiographic presentations of pulmonary TB and bacteriologic response during anti-TB treatment was evaluated between January 2007 and December 2011, comparing patients with and without DM. This is a retrospective unmatched case-control study conducted at a large national hospital. Cases and controls were randomly selected from patients diagnosed with pulmonary TB over a 5-year period. Sputum culture conversion was assessed after 2 months of anti-TB treatment.

Results

Clinical symptoms were similar between patients with and without DM. Patients with DM had a higher initial sputum acid-fast bacillus (AFB) smear grade and were less likely to have cavitary lesions on initial chest radiographs than patients without DM. Of 134 adults with DM and TB, 71 (53%) remained sputum culture positive after 2 months of anti-TB treatment, compared with 36 (27%) patients without DM.

Conclusions

DM was associated with atypical radiographic findings and delayed sputum culture conversion at 2 months in adults with pulmonary TB in Qatar. Increased health education of patients with DM about symptoms of TB, low thresholds for evaluation for active TB, and close monitoring of bacteriologic response to treatment among patients with TB and DM are warranted.

Burden and Characteristics of the Comorbidity Tuberculosis-Diabetes in Europe: TBnet Prevalence Survey and Case-Control Study

Background

The growing burden of diabetes mellitus (DM) is posing a threat to global tuberculosis (TB) control. DM triples the risk of developing TB, modifies the presenting features of pulmonary TB, and worsens TB treatment outcomes. We aimed to analyze the prevalence of DM among TB patients and to describe the characteristics and clinical presentation of TB-DM patients in Europe.

Methods

We performed a cross-sectional survey on the prevalence of DM among consecutively diagnosed adult TB patients in 11 European TB referral centers located in France, Germany, Greece, Italy, Russia, Slovakia, Spain, and the United Kingdom over the period 2007–2015. We also selected DM-TB cases and TB only controls with a 1:3 ratio to perform a case-control analysis, including patients selected from the countries mentioned above plus Norway and Ukraine.

Results

Among 3143 TB enrolled patients, DM prevalence overall was 10.7% and ranged from 4.4% in Greece to 28.5% in the United Kingdom. Patients’ median ages ranged from 36 to 49 years, and all centers had >60% males; the proportion of foreign-born patients varied widely across sites. In the case-control study, DM was independently associated with older age and, among older patients, with being foreign-born. Among patients with pulmonary involvement, cavities on chest imaging were more frequently observed among those with DM.

Conclusions

Diabetes mellitus represents a challenge for TB control in Europe, especially in foreign-born and in elderly patients. Specific screening strategies should be evaluated.

Prevalence of tuberculosis and multidrug resistant tuberculosis in the Middle East Region

INTRODUCTION

Prevalence of TB and MDR-TB varies considerably among various regions of World Health Organization (WHO) and also among individual countries within each region. Many Middle Eastern countries have war/civil war-like situations, refugees from war-torn countries or dynamic expatriate population from TB endemic countries which will likely affect the END-TB strategy launched by the WHO in 2015. Areas covered: The data for each of 17 countries comprising the Middle East were analyzed for estimated incidence of TB, number of notified TB cases, mortality rate, and rate of MDR-TB in new and previously treated TB cases as reported by WHO. Data from national surveys or surveillance studies from individual countries were also analyzed for incidence of MDR-TB in new and previously treated TB patients and compared with the estimated data by WHO. Expert commentary: Several Middle Eastern countries have low/intermediate incidence rate and are striving for TB elimination. Reaching pre-elimination (< 1 TB case per 100 000 population) stage will require testing and treatment of latent TB infection in groups at high risk of reactivation and effective treatment of drug-susceptible and drug-resistant TB cases. Large numbers of refugees, expatriate workers, or confounding noncommunicable diseases in some countries pose major challenges in achieving progress toward TB elimination.

Stress Hyperglycemia in Patients with Tuberculosis Disease: Epidemiology and Clinical Implications

PURPOSE OF REVIEW

The intersection of tuberculosis (TB) disease and type 2 diabetes mellitus is severely hindering global efforts to reduce TB burdens. Diabetes increases the risk of developing TB disease and negatively impacts TB treatment outcomes including culture conversion time, mortality risk, and TB relapse. Recent evidence also indicates plausible mechanisms by which TB disease may influence the pathogenesis and incidence of diabetes. We review the epidemiology of stress hyperglycemia in patients with TB and the pathophysiologic responses to TB disease that are related to established mechanisms of stress hyperglycemia. We also consider clinical implications of stress hyperglycemia on TB treatment, and the role of TB disease on risk of diabetes post-TB.

RECENT FINDINGS

Among patients with TB disease, the development of stress hyperglycemia may influence the clinical manifestation and treatment response of some patients and can complicate diabetes diagnosis. Research is needed to elucidate the relationship between TB disease and stress hyperglycemia and determine the extent to which stress hyperglycemia impacts TB treatment response. Currently, there is insufficient data to support clinical recommendations for glucose control among patients with TB disease, representing a major barrier for efforts to improve treatment outcomes for patients with TB and diabetes.

Diabetes is associated with increased prevalence of latent tuberculosis infection: Findings from the National Health and Nutrition Examination Survey, 2011-2012

AIMS

We aim to determine the association between prediabetes and diabetes with latent TB using National Health and Nutrition Examination Survey data.

METHODS

We performed a cross-sectional analysis of 2011-2012 National Health and Nutrition Examination Survey data. Participants ≥20 years were eligible. Diabetes was defined by glycated hemoglobin (HbA1c) as no diabetes (≤5.6% [38 mmol/mol]), prediabetes (5.7-6.4% [39-46 mmol/mol]), and diabetes (≥6.5% [48 mmol/mol]) combined with self-reported diabetes. Latent TB infection was defined by the QuantiFERON®-TB Gold In Tube (QFT-GIT) test. Adjusted odds ratios (aOR) of latent TB infection by diabetes status were calculated using logistic regression and accounted for the stratified probability sample.

RESULTS

Diabetes and QFT-GIT measurements were available for 4958 (89.2%) included participants. Prevalence of diabetes was 11.4% (95%CI 9.8-13.0%) and 22.1% (95%CI 20.5-23.8%) had prediabetes. Prevalence of latent TB infection was 5.9% (95%CI 4.9-7.0%). After adjusting for age, sex, smoking status, history of active TB, and foreign born status, the odds of latent TB infection were greater among adults with diabetes (aOR 1.90, 95%CI 1.15-3.14) compared to those without diabetes. The odds of latent TB in adults with prediabetes (aOR 1.15, 95%CI 0.90-1.47) was similar to those without diabetes.

CONCLUSIONS

Diabetes is associated with latent TB infection among adults in the United States, even after adjusting for confounding factors. Given diabetes increases the risk of active TB, patients with co-prevalent diabetes and latent TB may be targeted for latent TB treatment.