Hemoglobin A1c (HbA1c) Rate of Change (24-hour)
This test measures how quickly your hemoglobin A1c levels change over a 24-hour period. It helps assess how your blood sugar is being managed over time.
["Understanding how fast your blood sugar control may be improving or worsening can help guide treatment decisions."]
Key facts at a glance
- LOINC
- 45362-1
- Short code
- LPT 0.50 ug PW Bld-nRate
- Synonyms
- LPT 0.50 ug PW Bld-nRate
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85610
- SNOMED
- 396252006
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What Does This Test Measure?
HbA1c is a form of hemoglobin that carries oxygen in your blood, modified by your blood sugar levels over roughly three months. This test specifically tracks the *rate* at which your HbA1c levels shift within a 24-hour window, often used alongside traditional HbA1c values to evaluate recent trends in glucose control.
Why Is This Test Done?
Your healthcare provider may order this test if they suspect your blood sugar management isn’t stable. It helps identify whether recent changes in diet, medication, or activity are improving or worsening your glucose control.
How Is This Test Performed?
A small blood sample is taken, typically from your arm. The lab analyzes it to determine the rate of change in your HbA1c levels over the past day, often compared to your baseline HbA1c value.
What Do Results Mean?
Results are qualitative (not numerically reported) and interpreted in relation to your overall HbA1c level and clinical context. A positive or increasing rate may suggest improved control, while a negative or decreasing rate could indicate worsening management.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
HbA1c Change Rate
Frequently asked questions
How often should I get this test?
What if my results are abnormal?
Does diet or exercise affect this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy