Why it is performed
- Screen and diagnose diabetes using appropriate clinical criteria.
- Monitor glycaemic control in people with diabetes.
- Assess hyperglycaemia or hypoglycaemia with symptoms and medication.
How it is performed
Glucose is measured in a current sample. HbA1c measures the proportion of haemoglobin bound to glucose and is not determined by a single meal.
Preparation
- For fasting glucose, consume no calories for the stated period; water is allowed unless told otherwise.
- Do not change insulin or diabetes medication without instructions.
- Report anaemia, haemoglobin variants, transfusion, pregnancy or kidney disease because they can alter HbA1c.
How Askabide processes it
At Askabide
Glucose may be processed by dry chemistry. HbA1c is performed with the available validated method or referred if the reagent or procedure is not operational.
The main analytical phase is performed in the centre’s laboratory, subject to availability and validation.
Results and indicative intervals
Intervals vary by method, analyser, reagent, units, age, sex, pregnancy, menstrual-cycle phase and reference population. The valid interval is the one printed on the laboratory report.
| Parameter or result | Indicative reference | How it is interpreted |
|---|---|---|
| Normal fasting glucose | 70–99 mg/dL | Interpret with actual fasting duration and clinical context. |
| Impaired fasting glucose | 100–125 mg/dL | Usually requires confirmation and metabolic-risk assessment. |
| Criterion compatible with diabetes | ≥126 mg/dL en ayunas | Usually confirmed on another occasion unless hyperglycaemia is unequivocal. |
| Usual HbA1c | <5,7 % | Does not exclude diabetes in every circumstance. |
| Increased-risk HbA1c | 5,7–6,4 % | Compatible with prediabetes under common criteria; needs assessment. |
| HbA1c compatible with diabetes | ≥6,5 % | Requires confirmation if symptoms or unequivocal hyperglycaemia are absent. |
Important limitations
- HbA1c may be unreliable when red-cell lifespan is altered.
- A single normal glucose does not exclude abnormalities at other times.
- Treatment targets are individualised and are not always the same as the interval for people without diabetes.