Glycemic changes common in patients with tuberculosis but no diabetes

Glycemic changes may play an important role in response to treatment among patients with tuberculosis who do not have diabetes, according to data published in the American Journal of Respiratory Critical Care Medicine.

“Several studies have found that patients with newly-diagnosed tuberculosis often have abnormal and inconsistent glycemic measurements when tuberculosis is diagnosed, during tuberculosis treatment and after treatment,” Qiao Liu, MD, with the department of chronic communicable disease at the CDC of Jiangsu Province and the department of epidemiology at the School of Public Health at Nanjing Medical University, China, and colleagues wrote. “Distinct glycemic trajectories after tuberculosis diagnosis are not well characterized and whether patients with stress hyperglycemia have poor treatment outcomes is not known.”

Researchers identified 500 patients (median age, 42 years; 65.2% men) with newly-diagnosed, drug-susceptible tuberculosis who had at least three fasting plasma glucose tests at the time of diagnosis and during the third and sixth months of treatment. At 2 and 4 months post-treatment, all patients underwent an additional fasting plasma glucose test.

In the cohort, 405 patients had five fasting plasma glucose tests from tuberculosis diagnosis to post-treatment and 95 participants had three tests.

Researchers observed the following distinct glycemic trajectories from time of tuberculosis diagnosis to post-treatment:

• consistently normal glycemic testing results (43%);
• transient hyperglycemia (24%);
• erratic glycemic instability (12%);
• diabetes (16%); and
• consistent hyperglycemia without diabetes (6%)

Patients with transient hyperglycemia were more likely to experience treatment failure (adjusted OR = 4.20; 95% CI, 1.57-11.25; P = .004) or erratic glycemic instability (adjusted OR = 5.98; 95% CI, 2.00-17.87; P = .001) compared with those with a consistently normal glycemic trajectory. Patients with diabetes also had an increased risk for treatment failure (adjusted OR = 6.56; 95% CI, 2.22-19.35; P = .001); this risk was modified by glycemic control and metformin.

“Glycemic changes, regardless of diabetes status, may be an important marker for the patient response to tuberculosis treatment,” the researchers wrote. “Understanding potential mechanisms for these changes may be useful for providing risk-stratified approaches to antituberculosis treatment.”