Abstract

Background: Glycated haemoglobin (HbA1c) is a cornerstone biomarker for longterm glycemic control in diabetes mellitus. While its clinical utility is globally recognized, its interpretation in India is complicated by biological, methodological, and infrastructural factors. This review synthesizes insights from UK-based case studies and recent Indian and international literature to contextualize HbA1c measurement, interpretation, and relevance in Indian healthcare settings. Methods: The review integrates content from the book “HbA1c in Diabetes: Case Studies Using IFCC Units” with peer-reviewed studies on HbA1c variability, hemoglobinopathies, anaemia, and monitoring strategies. Emphasis is placed on Indian-specific challenges such as inconsistent adoption of IFCC standards, high prevalence of iron-deficiency anaemia, and haemoglobin variants. Results: HbA1c interpretation in India is influenced by assay variability, biological confounders, and limited standardization. Case-based nsights highlight the need for alternative markers like fructosamine and continuous glucose monitoring (CGM) in select populations. Regular HbA1c monitoring improves outcomes, but access and affordability remain barriers. Conclusion: HbA1c remains indispensable in Indian diabetes care, but its interpretation must be individualised. Standardisation, contextual awareness, and integration with digital tools are essential for optimising outcomes.

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