Lancet Study Flags Inaccuracies in HbA1c Tests for Diabetes Diagnosis in India

Key facts

• A study published in The Lancet Regional Health found that glycated hemoglobin (HbA1c) tests may not accurately reflect blood glucose levels, potentially misrepresenting India’s diabetes burden.
• The study indicates that conditions affecting hemoglobin quantity, structure, or lifespan, such as anemia, hemoglobinopathies, and red blood cell enzyme (G6PD) deficiency, can distort HbA1c values.
• Exclusive reliance on HbA1c could delay the diagnosis of Type-2 diabetes by up to four years in men with undetected G6PD deficiency.
• According to data from 2025 cited in the study, more than 50% of the population in some Indian regions are nutritionally challenged with widespread iron deficiency anemia.
• For low-resource settings, the researchers recommend the Oral Glucose Tolerance Test (OGTT) for diagnosis, involving two glucose values taken fasting and two hours after ingesting 75 gm of glucose.
• The study suggests Self-Monitoring of Blood Glucose (SMBG) using glucose metres two to three times weekly, combined with basic hematologic screening, for monitoring in low-resource areas.
• In tertiary care settings, the framework suggests combining HbA1c with OGTT for diagnosis and using Continuous Glucose Monitoring (CGM) with alternative markers like fructosamine for monitoring.