Point-of-care glycated hemoglobin a1c testing for the identification of hyperglycemia severity among individuals with dual tuberculosis and diabetes mellitus in Tanzania

BACKGROUND: Poor glycemic control during tuberculosis (TB) treatment is challenging, as the optimum treatment strategy remains unclear. We assessed hyperglycemia severity using glycated hemoglobin (HbA1c) test and predictors of severe hyperglycemia at the time of TB diagnosis in three resources-diverse regions in Tanzania.

METHODS: This was a substudy from a large cohort study implemented in three regions of Tanzania. TB individuals with diabetes mellitus (DM) (prior history of DM or newly diagnosed DM) were assessed for hyperglycemic levels using HbA1c test and stratified as mild (<53 mmol/mol), moderate (≥53-<86 mmol/mol), and severe (≥86 mmo/mol).

RESULTS: From October 2019 to September 2020, 1344 confirmed TB individuals were screened for DM and 105 (7.8%) individuals had dual TB/DM and were assessed for glycemic levels. Of these, 69 (67.7%) had a prior history of DM and 26 (24.8%) were living with human immunodeficiency virus. Their mean age was 49.0 (±15.0) years and 56.2% were male. The majority (77.1%) had pulmonary TB, and 96.2% were newly diagnosed TB individuals. HbA1c test identified 41(39.0%), 37 (35.2%), and 27 (25.7%) individuals with severe, moderate, and mild the hyperglycaemia respectively. Female sex (odds ratio [OR]: 3.55, 95% confidence interval [CI]: 1.06-11.92, P = 0.040) and previous history of DM (OR: 3.71, 95% CI: 1.33-10.33, P = 0.013) were independent risk factors for severe hyperglycemic at the time of TB diagnosis.

CONCLUSION: By integrating early HbA1c testing, a substantial proportion of individuals with severe hyperglycemia were identified. HbA1c testing can be recommended to identify and triage patients requiring personalized intensified DM management in resource-limited programmatic settings.