Transient hyperglycemia tied to higher risk of unfavourable treatment outcome in pulmonary TB

Researchers note the common occurrence of transient hyperglycemia during tuberculosis (TB) treatment, yet there seems to be no clarity on its association with unfavourable treatment outcomes. Geeta Pardeshi, Grant Government Medical College and Sir JJ Hospitals, Mumbai, India, and colleagues aimed to determine whether there is an association between glycated Haemoglobin (HbA1c) trajectories and tuberculosis treatment outcomes.

For this purpose, the researchers prospectively evaluated adults with pulmonary tuberculosis for 18 months after their second HbA1c measurement.

HbA1c trajectories during the initial three months of treatment were defined as follows – Incident hyperglycemia: HbA1c < 6.5% at baseline and ≥ 6.5% at three-month follow-up; Transient hyperglycemia: HbA1c ≥ 6.5% at baseline and <6.5% at three-month follow-up; Persistent hyperglycemia: HbA1c ≥ 6.5% at baseline and three-month follow-up; Persistent euglycemia: HbA1c < 6.5% at baseline and three-month follow-up.

Persistent euglycemia: HbA1c < 6.5% at baseline and three-month follow-up; Persistent hyperglycemia: HbA1c ≥ 6.5% at baseline and three-month follow-up; Transient hyperglycemia: HbA1c ≥ 6.5% at baseline and <6.5% at three-month follow-up; Incident hyperglycemia: HbA1c < 6.5% at baseline and ≥ 6.5% at three-month follow-up.

The association between HbA1c trajectories and unfavourable treatment outcomes of all-cause mortality, recurrence, and failure was measured using Multivariable Poisson regression.

The study led to the following findings:

• Of the 587 participants, 76% had persistent euglycemia, 20% had persistent hyperglycemia, and 4% had transient hyperglycemia.
• One participant had an incident of hyperglycemia and was excluded.
• Compared to participants with persistent euglycemia, those with transient hyperglycemia had a two-fold higher risk of experiencing an unfavourable treatment outcome (aIRR=2.07) after adjusting for confounders including diabetes treatment, and Body-Mass Index; a significant association with persistent hyperglycemia (aIRR=1.64) was not found.
• Diabetes treatment was associated with a significantly lower risk of unfavourable treatment outcomes (aIRR=0.38).

"Lack of diabetes treatment and transient hyperglycemia was associated with a higher risk of unfavourable treatment outcomes in adults with pulmonary tuberculosis," the researchers concluded.

Reference:

Pardeshi, G., Mave, V., Gaikwad, S., Kadam, D., Barthwal, M., Gupte, N., Atre, S., Deshmukh, S., Golub, J. E., & Gupte, A. (2023). Glycated Haemoglobin Trajectories and their Association with Treatment Outcomes among Pulmonary Tuberculosis Cases in India - A Prospective Cohort Study. CHEST. https://doi.org/10.1016/j.chest.2023.08.026