Glycated Hemoglobin

Definition

A form of hemoglobin resulting from non-enzymatic fixation of glucose on hemoglobin. It reflects average glycemic levels over 2-3 months.

How it works

Glycated hemoglobin, denoted HbA1c, forms when blood glucose binds to hemoglobin molecules. Unlike fluctuating glycemic levels, HbA1c represents a weighted average of glucose levels throughout the lifespan of red blood cells (120 days). A level below 5.7% is considered normal in non-diabetics, while a level between 5.7% and 6.4% indicates pre-diabetes. A level above 6.5% confirms diabetes diagnosis.

Role

Enables diabetes diagnosis and monitoring by reflecting medium-term glycemic control.

Examples

• Screening for type 2 diabetes
• Monitoring glycemic control in diabetics
• Diagnosing pre-diabetes
• Evaluating complication risk

Recommendations

Annual HbA1c dosage is recommended for high-risk individuals, and every 3 months for diabetics. Therapeutic targets typically range from 6.5% to 7.5% depending on patient profile.

Key takeaway

HbA1c is the standard tool for evaluating long-term glycemic control.

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