Trends in HbA1c levels and implications for diabetes screening in tuberculosis cases undergoing treatment in India.

SETTING: The optimal timing of screening for diabetes mellitus (DM) among tuberculosis (TB) cases is unclear due to the possibility of stress hyperglycemia. DESIGN: We evaluated adult (18 years) pulmonary TB cases at treatment initiation as well as at 3 months, 6 months and 12 months. DM was identified by self-report (known DM) or glycated hemoglobin (HbA1c)  6.5% (new DM). Trends in HbA1c levels during treatment were assessed using non-parametric tests. RESULTS: Of the 392 participants enrolled, 75 (19%) had DM, 30 (40%) of whom had new DM. Of the 45 participants with known DM, respectively 37 (82%) and 40 (89%) received medication to lower glucose levels at treatment initiation and completion; one participant with new DM initiated glucose-lowering medication during follow-up. The median HbA1c level in participants with known, new and no DM was respectively 10.1% (interquartile range [IQR] 8.3-11.6), 8.5% (IQR 6.7-11.5) and 5.6% (IQR 5.3-5.9) at treatment initiation, and 8.7% (IQR 6.8-11.3), 7.1% (IQR 5.8-9.5) and 5.3% (IQR 5.1-5.6) at treatment completion (P < 0.001). Overall, 5 (12%) with known and 13 (43%) with new DM at treatment initiation had reverted to HbA1c < 6.5% by treatment completion (P = 0.003); the majority of reversions occurred during the first 3 months, with no significant reversions beyond 6 months. CONCLUSION: HbA1c levels declined with anti-tuberculosis treatment. Repeat HbA1c testing at treatment completion could reduce the risk of misdiagnosis of DM.

Prevalence of dysglycemia and clinical presentation of pulmonary tuberculosis in Western India.

SETTING: Pune, India. OBJECTIVES: To estimate the prevalence and risk factors of pre-diabetes mellitus (DM) and DM, and its associations with the clinical presentation of tuberculosis (TB). DESIGN: Screening for DM was conducted among adults (age  18 years) with confirmed TB between December 2013 and January 2017. We used multinomial regression to evaluate the risk factors for pre-DM (glycated hemoglobin [HbA1c]  5.7-6.5% or fasting glucose 100-125 mg/dl) and DM (HbA1c  6.5% or fasting glucose  126 mg/dl or random blood glucose > 200 mg/dl or self-reported DM history/treatment) and the association of dysglycemia with the severity of TB disease. RESULTS: Among 1793 participants screened, 890 (50%) had microbiologically confirmed TB. Of these, 33% had pre-DM and 18% had DM; 41% were newly diagnosed. The median HbA1c level among newly diagnosed DM was 7.0% vs. 10.3% among known DM (P < 0.001). DM (adjusted OR [aOR] 4.94, 95%CI 2.33-10.48) and each per cent increase in HbA1c (aOR 1.42, 95%CI 1.01-2.01) was associated with >1+ smear grade or 9 days to TB detection. CONCLUSION: Over half of newly diagnosed TB patients had DM or pre-DM. DM and increasing dysglycemia was associated with higher bacterial burden at TB diagnosis, potentially indicating a higher risk of TB transmission to close contacts.