Effect of diabetes mellitus on risk of latent TB infection in a high TB incidence area: a community-based study in Taiwan

Abstract

ObjectiveTo investigate the association between diabetes and latent tuberculosis infections (LTBI) in high TB incidence areas.DesignCommunity-based comparison study.SettingOutpatient diabetes clinics at 4 hospitals and 13 health centres in urban and rural townships. A community-based screening programme was used to recruit non-diabetic participants.ParticipantsA total of 2948 patients with diabetes aged older than 40 years were recruited, and 453 non-diabetic participants from the community were enrolled.Primary and secondary outcome measuresThe interferon-gamma release assay (IGRA) and the tuberculin skin test were used to detect LTBI. The IGRA result was used as a surrogate of LTBI in logistic regression analysis.ResultsDiabetes was significantly associated with LTBI (adjusted OR (aOR)=1.59; 95% CI 1.11 to 2.28) and age correlated positively with LTBI. Many subjects with diabetes also had additional risk factors (current smokers (aOR=1.28; 95% CI 0.95 to 1.71), comorbid chronic kidney disease (aOR=1.26; 95% CI 1.03 to 1.55) and history of TB (aOR=2.08; 95% CI 1.19 to 3.63)). The presence of BCG scar was protective (aOR=0.66; 95% CI 0.51 to 0.85). Duration of diabetes and poor glycaemic control were unrelated to the risk of LTBI.ConclusionThere was a moderately increased risk of LTBI in patients with diabetes from this high TB incidence area. This finding suggests LTBI screening for the diabetics be combined with other risk factors and comorbidities of TB to better identify high-risk groups and improve the efficacy of targeted screening for LTBI.

Phenotype Definition for “Resisters” to Mycobacterium tuberculosis Infection in the Literature—A Review and Recommendations

“…Finally, when using TST and IGRA tests, it is important to consider and collect information on factors that are associated with a positive result. For example, associations with smoking and diabetes have been established with positive TST and IGRA ( 81 – 84 ). Socio-economic factors such as low income and education, male sex, race, older age and HHC were identified as predictive factors for positive TST and IGRA results by Mahomed et al.…”

The Interaction of Diabetes and Tuberculosis: Translating Research to Policy and Practice

“…However, most of the studies included in this review were cross sectional in design and had significant limitations. In particular, few of the studies included used laboratory methods to screen for undiagnosed diabetes and most included only those with known diabetes in the exposure category, resulting in misclassification of diabetes and potentially underestimating the risk of LTBI associated with diabetes [ 19 ]. One recently published US cross-sectional study screened all refugees for diabetes using glycated haemoglobin (HbA1c).…”

“…One recently published US cross-sectional study screened all refugees for diabetes using glycated haemoglobin (HbA1c). This showed higher infections risks and a graded response, with increased risk of LTBI among people with “pre-diabetes” (HbA1c 5.7–6.4%; OR 1.7, 95% CI 1.1–2.4) and higher among those with diabetes (OR 2.3, 95% CI 1.2–4.5) [ 20 ] A community based study from Taiwan with more robust case and outcome definitions also identified an increased risk (OR: 1.59; 95% CI 1.11 to 2.28) [ 19 ]. Cohort studies following patients with newly diagnosed diabetes to determine LTBI status would improve understanding of the magnitude of M. tuberculosis infection risk and potential mechanisms but are obviously difficult to carry out in LMIC.…”

“…Even after TB treatment success TB patients remain at increased mortality risk, possibly due to increased cardiovascular risk regardless of whether or not they have diabetes [28,33,34], although most studies have significant limitations (including limited follow-up time, lack of control of key confounders, or inappropriate selection of control series) [35]. [18][19][20]24,27] in text for evidence for and magnitude of possible relationships between diabetes and TB susceptibility, TB disease and prognosis).…”

“…Cause of death during treatment among people with TB and diabetes is not always clearly reported, but not only diabetes but also TB is associated with an increased risk of cardiovascular complications such as myocardial infarction [28,29] and stroke [30], possibly explaining the higher rate of deaths in the first few months of TB treatment in patients who also have diabetes [31,32]. Even after TB treatment success TB patients remain at increased mortality risk, possibly due to increased cardiovascular risk regardless of whether or not they have [18][19][20]24,27] in text for evidence for and magnitude of possible relationships between diabetes and TB susceptibility, TB disease and prognosis).…”