Reporting of glycemic variability from continuous glucose monitoring
In one aspect, a method of estimating an HbA1c level is provided. The method may include obtaining a first and second glucose measurement, adding the first and the second glucose measurements to a glucose measurement data set, and calculating an estimated HbA1c level using at least the glucose measurement data set. In another aspect, a method of calculating a range of an estimated HbA 1c level is provided. The method may comprise at least calculating an estimated HbA 1c level and a standard deviation of the estimated HbA 1c level using a glucose measurement data set, and combining the estimated HbA 1c level with the standard deviation of the estimated HbA 1c level to acquire the range of the estimated HbA 1c level. In another aspect, a glucose monitoring device may display glycemic variability of an individual.
1. An analyte monitoring method comprising:
using an analyte monitoring sensor of an analyte monitoring system to measure glucose levels of a patient, wherein using the analyte monitoring sensor of the analyte monitoring system to measure the glucose levels of the patient comprises using a fluorometer of the analyte monitoring sensor to measure the glucose levels of the patient, using the fluorometer of the analyte monitoring sensor to measure the glucose levels of the patient comprises using the fluorometer to measure parameters of fluorescence after and/or during excitation by a spectrum of light, and the measured parameters include an intensity and/or a wavelength distribution of emission spectrum of the fluorescence;
using the analyte monitoring sensor to communicate over a wireless communication link;
using an analyte monitoring device of the analyte monitoring system to obtain a first glucose measurement indicative of a first glucose level of the patient;
using the analyte monitoring device to obtain a second glucose measurement indicative of a second glucose level of the patient;
using the analyte monitoring device to add the first and the second glucose measurements to a glucose measurement data set;
using a processor of the analyte monitoring device to calculate an estimated HbA 1c level using the glucose measurement data set, an association constant k 2 , and an association constant k 3 , wherein the association constant k 2 represents a conversion of a pre-A 1c to an HbA 1c , and the association constant k 3 represents a life span of the pre-A 1c and the HbA 1c ; and
using a display of the analyte monitoring device to display the estimated HbA 1c level.
2. The method of claim 1 , wherein calculating the estimated HbA 1c level comprises taking a convolution of a first function and a second function, wherein the first function includes the glucose measurement data set, and the second function includes the association constant k 2 and the association constant k 3 .
3. The method of claim 2 , wherein the first function further includes an association constant K eq that represents an equilibrium constant of glucose.
4. The method of claim 2 , wherein the second function further includes an association constant k 1 and an association constant k −1 , the association constant k 1 represents a binding constant when a glucose attaches to a hemoglobin to form the pre-A 1c , and the association constant k −1 represents a dissociation constant when the glucose detaches from the hemoglobin.
5. The method of claim 1 , further comprising:
using the analyte monitoring device to receive a blood HbA 1c measurement; and
using the analyte monitoring device to calibrate one or more of the first and second functions using the received blood HbA 1c measurement.
6. The method of claim 5 , wherein calibrating the one or more of the first and second functions comprises:
adjusting one or more of the association constant k 2 , the association constant k 3 , the association constant K eq , the association constant k 1 , and the association constant k −1 .
7. The method of claim 1 , wherein the glucose levels are interstitial fluid glucose levels.
8. The method of claim 1 , further comprising employing the measured parameters to identify a presence and/or an amount of specific molecules in a medium.
9. The method of claim 1 , wherein the analyte monitoring sensor is an implantable sensor inserted subcutaneously inside the patient.
10. The method of claim 1 , wherein the analyte monitoring system obtains the first and second glucose measurements directly from the analyte monitoring sensor.
11. The method of claim 1 , wherein the analyte monitoring system obtains the first and second glucose measurements from a transceiver of the analyte monitoring system.
12. The method of claim 1 , further comprising using a transceiver of the analyte monitoring system to receive the measured parameters from the analyte monitoring sensor, wherein the analyte monitoring device obtains the first and second glucose measurements from the transceiver.
13. The method of claim 1 , further comprising:
using the processor of the analyte monitoring device to calculate a standard deviation of the estimated HbA 1c level using the glucose measurement data set;
using the processor of the analyte monitoring device to combine the estimated HbA 1c level with the standard deviation of the estimated HbA 1c level to acquire a range of the estimated HbA 1c level; and
using a display of the analyte monitoring device to display the range of the estimated HbA 1c level.
14. The method of claim 1 , wherein the processor of the analyte monitoring device uses the following formula to calculate the estimated HbA 1c level:
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=
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where k 1 is an association constant that represents a binding constant when a glucose attaches to a hemoglobin to form the pre-A 1c , and k −1 is an association constant that represents a dissociation constant when the glucose detaches from the hemoglobin.
15. An analyte monitoring method comprising:
using an analyte monitoring sensor of an analyte monitoring system to measure glucose levels of a patient, wherein using the analyte monitoring sensor of the analyte monitoring system to measure the glucose levels of the patient comprises using a fluorometer of the analyte monitoring sensor to measure the glucose levels of the patient, using the fluorometer of the analyte monitoring sensor to measure the glucose levels of the patient comprises using the fluorometer to measure parameters of fluorescence after and/or during excitation by a spectrum of light, and the measured parameters include an intensity and/or a wavelength distribution of emission spectrum of the fluorescence;
using the analyte monitoring sensor to communicate over a wireless communication link;
using an analyte monitoring device of the analyte monitoring system to obtain a first glucose measurement indicative of a first glucose level of the patient;
using the analyte monitoring device to obtain a second glucose measurement indicative of a second glucose level of the patient;
using the analyte monitoring device to add the first and the second glucose measurements to a glucose measurement data set;
using a processor of the analyte monitoring device to calculate an estimated HbA 1c level using the glucose measurement data set and the following formula:
[
H
b
A
1
c
]
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H
b
]
(
mmol
mol
)
=
[
G
L
U
]
(
t
)
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1
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2
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-
1
+
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3
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-
(
k
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+
k
2
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t
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where k 1 is an association constant that represents a binding constant when a glucose attaches to a hemoglobin to form a pre-A 1c , k −1 is an association constant that represents a dissociation constant when the glucose detaches from the hemoglobin, k 2 is an association constant that represents a conversion of the pre-A 1c to an HbA 1c and k 3 is an association constant that represents a life span of the pre-A 1c and the HbA 1c ;
using the processor of the analyte monitoring device to calculate a standard deviation of the estimated HbA 1c level using the glucose measurement data set;
using the processor of the analyte monitoring device to combine the estimated HbA 1c level with the standard deviation of the estimated HbA 1c level to acquire a range of the estimated HbA 1c level; and
using a display of the analyte monitoring device to display the range of the estimated HbA 1c level.
16. The method of claim 15 , wherein the glucose levels are interstitial fluid glucose levels.
17. The method of claim 15 , further comprising employing the measured parameters to identify a presence and/or an amount of specific molecules in a medium.
18. The method of claim 15 , wherein the analyte monitoring sensor is an implantable sensor inserted subcutaneously inside the patient.
19. The method of claim 15 , wherein the analyte monitoring system obtains the first and second glucose measurements directly from the analyte monitoring sensor.
20. The method of claim 15 , wherein the analyte monitoring system obtains the first and second glucose measurements from a transceiver of the analyte monitoring system.
21. The method of claim 15 , further comprising using a transceiver of the analyte monitoring system to receive the measured parameters from the analyte monitoring sensor, wherein the analyte monitoring device obtains the first and second glucose measurements from the transceiver.