An Overview of Research on Cgm Vs Fingerstick Testing: What’S The Difference
Both continuous glucose monitors (CGMs) and fingerstick blood glucose tests provide information about blood glucose levels. The primary difference lies in how the measurement is taken: fingerstick tests offer a single point-in-time reading, while CGMs provide ongoing glucose data.
Key takeaways
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Fingerstick testing uses a small blood sample from a finger to measure glucose.
CGMs use a sensor inserted under the skin to track glucose levels continuously.
CGMs provide trend information, showing how glucose levels change over time.
Fingerstick tests offer a precise reading at a specific moment.
CGMs may require calibration with fingerstick tests.
Both methods have potential for user error.
The choice between CGM and fingerstick testing often depends on individual needs and preferences.
Both methods are tools, and neither is inherently “better.”
Why this happens
Fingerstick testing directly measures glucose in a blood sample. CGMs, on the other hand, measure glucose in the interstitial fluid, the fluid surrounding cells. This means there can be a slight delay between a change in blood glucose and the CGM reading.
Real-world scenarios
A common situation involves planning travel. A person using a CGM may notice their glucose levels trending upwards after a meal. This information can influence decisions about food choices. Conversely, someone relying on fingerstick testing might only get a snapshot of their glucose levels at specific times, potentially missing the trend.
Another scenario involves a busy school day. A student might use a CGM to monitor glucose levels during classes and activities. If the CGM indicates a low glucose level, the student can take action, such as eating a snack. Someone using fingerstick testing would need to stop what they are doing to test, which can be disruptive.
Risk factors and considerations
| Risk factor | Why it matters | Who is most affected | Considerations |
|---|---|---|---|
| Inconsistent testing schedule | Can lead to missed high or low glucose events. | People with any type of diabetes. | Regularly discussing testing schedules with a healthcare provider. |
| Incorrect technique | Can result in inaccurate readings. | People new to either method. | Reviewing proper testing techniques with a healthcare professional. |
| Sensor placement (CGM) | Can affect the accuracy of CGM readings. | CGM users. | Following manufacturer’s instructions for sensor insertion. |
| Calibration errors (CGM) | Can lead to inaccurate CGM readings. | CGM users. | Calibrating the CGM as instructed by the manufacturer. |
| Medication use | Certain medications can affect glucose levels. | People taking medications that affect glucose. | Being aware of potential medication effects on glucose levels. |
Symptoms and early signs
Both high and low blood glucose levels can cause symptoms. High blood glucose (hyperglycemia) may cause increased thirst, frequent urination, and blurred vision. Low blood glucose (hypoglycemia) may cause shakiness, sweating, and confusion. It’s important to note that symptoms can vary from person to person, and some people may not experience any symptoms at all.
How it’s checked
Fingerstick testing involves using a lancet to prick the finger and a blood glucose meter to analyze the blood sample. CGM systems involve inserting a sensor under the skin, which continuously measures glucose levels. The sensor transmits data to a receiver or a smartphone app.
What this means in everyday life
The information provided by both methods can influence decisions about food, exercise, and other lifestyle choices. However, it’s important to remember that neither method is perfect. Understanding the limitations of each method is crucial for interpreting the results.
Red flags: when to seek medical advice
Contact a healthcare provider if you experience severe symptoms of high or low blood glucose. Also, seek medical advice if you are experiencing frequent or unexplained fluctuations in your glucose levels, or if you have any concerns about your diabetes management.
Why people get confused
People often get confused because both CGMs and fingerstick tests measure the same thing: blood glucose. However, the way they measure it and the information they provide are different. The continuous nature of CGM data can be overwhelming for some, while the single-point readings of fingerstick tests may not always capture the full picture.
Here’s the part most people miss:
Many people focus solely on the numbers and forget that both methods are tools. The context of the reading is just as important.
Questions to ask your healthcare provider
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How is CGM technology commonly discussed in research?
What is known about the accuracy of CGMs compared to fingerstick testing?
Why do people associate CGMs with improved diabetes management?
What does research suggest about the use of CGMs in different populations?
How is fingerstick testing still relevant in the era of CGMs?
Frequently asked questions
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What is the difference between a CGM and a blood glucose meter?
How often should I calibrate my CGM?
Are CGMs always accurate?
Can I use a CGM instead of fingerstick testing?
What are the advantages and disadvantages of each method?
References
ADA, CDC, WHO, NIH/NIDDK, Mayo Clinic, Cleveland Clinic
The information provided in this overview is intended for general knowledge and informational purposes only, and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment. The use of a product like Lifebetic should always be discussed with your healthcare provider.
Medical Disclaimer
The information provided in this article is for general informational and educational purposes only. It does not replace professional medical advice, diagnosis, or treatment. If you have any questions or concerns about your health, always consult a qualified healthcare professional.
