NEW DELHI: The widely used glycated haemoglobin (HbA1c) test, a standard tool for diagnosing and monitoring diabetes, may not accurately reflect blood glucose levels in millions of Indians, particularly in regions with a high prevalence of anaemia, haemoglobinopathies and red blood cell enzyme (G6PD) deficiency, a Lancet study said.
The study, published in The Lancet Regional Health–Southeast Asia, said reliance on HbA1c alone could delay diabetes diagnosis by up to four years in men with undetected G6PD deficiency, a hereditary genetic disorder affecting red blood cells, thereby increasing the risk of complications.
Questioning the use of HbA1c as the sole diagnostic or monitoring tool for type 2 diabetes in South Asia, especially India, the study recommended combining it with other tests for accurate diagnosis and follow-up.
“Relying exclusively on HbA1c can result in misclassification of diabetes status,” said Prof Anoop Misra, corresponding author and Chairman of Fortis C-DOC Centre of Excellence for Diabetes. “Some individuals may be diagnosed late, while others could be misdiagnosed, affecting timely management.”
Dr Shashank Joshi, co-author and endocrinologist from Mumbai, said HbA1c readings can be influenced by red blood cell variations even in urban hospitals, with discrepancies likely to be greater in rural and tribal areas where anaemia is common. Another co-author, Dr Shambho Samrat Samajdar, stressed a comprehensive approach, recommending oral glucose tolerance tests, self-monitoring of blood glucose and haematological assessments.
The study concluded that using HbA1c as a standalone tool in South Asian populations may lead to underdiagnosis, inappropriate treatment and delayed care, and called for multiparametric diagnostic approaches.
HbA1c diabetes test not conclusive
Relying exclusively on HbA1c can result in misclassification of diabetes status In the Indian subcontinent, the rising number of people with type 2 diabetes (T2D) makes it essential to maintain good glycemic control to prevent a substantial burden of diabetes-related complications. It is imperative that T2D is properly diagnosed and monitored to reduce this burden and avoid adverse outcomes.
The reliance on HbA1c alone could delay diagnosis by up to four years in men with undetected G6PD deficiency - a hereditary genetic disorder that affects red blood cells - potentially increasing risk of complications
In some regions of India, people are nutritionally challenged with many suffering from iron deficiency anemia, which can distort HbA1c readings