Beyond HbA1c: Alternative Glycemic Biomarkers in Hemoglobinopathies, Malignancy, and Special Clinical Populations - A Review

Key Takeaways for GI Nurses

• HbA1c may not accurately reflect glycemic control in patients with hemoglobinopathies (such as sickle cell disease or thalassemia), requiring alternative biomarkers like fructosamine or glycated albumin for proper diabetes management
• Cancer patients undergoing treatment may have falsely elevated or decreased HbA1c levels due to altered red blood cell turnover, making alternative glycemic markers essential for accurate metabolic assessment
• Special populations including patients with chronic kidney disease, liver cirrhosis, or those receiving blood transfusions require individualized approaches to glycemic monitoring beyond standard HbA1c testing
• Understanding these limitations helps nurses better interpret laboratory values and collaborate with providers to optimize pre-procedural glycemic control in high-risk endoscopy patients

Clinical Relevance

For GI and endoscopy nurses, this research has significant implications for pre-procedural assessment and patient safety protocols. Many patients presenting for endoscopic procedures have comorbidities that fall into the special populations discussed in this review. When evaluating diabetic patients with concurrent liver disease, malignancy, or blood disorders, nurses must recognize that HbA1c values may not accurately reflect recent glycemic control. This knowledge is particularly crucial during pre-procedural screening, where understanding true glycemic status affects procedural risk stratification, sedation considerations, and post-procedural monitoring requirements.

The clinical impact extends to patient education and care coordination responsibilities. GI nurses frequently serve as liaisons between patients and the multidisciplinary team, making it essential to understand when alternative glycemic biomarkers might be more appropriate. For patients with hepatic dysfunction undergoing procedures like ERCP or EUS, or oncology patients requiring diagnostic or therapeutic endoscopy, nurses can advocate for more comprehensive glycemic assessment when HbA1c limitations are suspected. This enhanced understanding also supports more informed discussions with patients about their diabetes management and procedural risks.

From a unit operations perspective, this knowledge helps establish more robust pre-procedural protocols for complex patients. Endoscopy units can develop enhanced screening criteria that flag patients who may benefit from alternative glycemic monitoring, ensuring appropriate laboratory orders are placed and results are available before procedures. This proactive approach can reduce procedure delays, improve patient outcomes, and enhance the overall quality of care delivered in the endoscopy setting.

Bottom Line

GI nurses must recognize that HbA1c has significant limitations in patients with hemoglobinopathies, malignancy, and other special clinical conditions commonly encountered in endoscopy practice. Understanding when alternative glycemic biomarkers may be more appropriate enables better pre-procedural assessment, more accurate risk stratification, and improved patient safety outcomes, while positioning nurses as knowledgeable advocates for comprehensive diabetes care in complex patient populations.