Method and device for assessing carbohydrate-to-insulin ratio

• US 8,454,510 B2
• Filed: 06/20/2008
• Issued: 06/04/2013
• Est. Priority Date: 06/20/2007
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Medingo Ltd. (Roche Holding AG)
• Inventors: Yodfat, Ofer, Shapira, Gali, Gescheit, Iddo
• Primary Examiner(s): Angell, Jon E
• Application Number:
  US12/143,601
• Publication Number:
  US 20090018406A1
• Time in Patent Office: 1,810 Days
• Field of Search: 600/301, 600/365
• US Class Current: 600/365
• CPC Class Codes: A61B 2562/0295 Strip shaped analyte sensors for apparatus classified in A61B5/145 or A61B5/157 disposable multilayered or laminated electrodes G01N27/307; details of handling chemical test elements G01N33/4875
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/14503 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors A61B5/1459, A61B5/1464, A61B5/1473, A61B5/1482, A61B5/14865 take precedence
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: A61K 38/28 Insulins
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2005/14268 with a reusable and a disposable component
• CPC Class Codes: A61M 2005/1726 the body parameters being measured at, or proximate to, the infusion site
• CPC Class Codes: A61M 2205/3569 sublocal, e.g. between console and disposable
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems

Abstract

A system and a method for determining an assessed carbohydrate to insulin ratio of a patient is described. The system and the method can comprise a memory component adapted for storing an initial set of values comprising at least one of a blood glucose level, a target blood glucose level, an insulin sensitivity, and, an estimated carbohydrate to insulin ratio. The system and the method can also comprise a bolus selection component adapted for selecting a test bolus corresponding to the determined initial set of values and a planned meal. In one implementation, the bolus selection component can receive bolus dose input from a user. In another implementation, the bolus selection component can estimate the bolus dose using a set of available inputs (e.g. the amount of carbohydrates in the planned meal). The system and the method can further comprise a user interface component adapted for receiving a confirmation that the test bolus has been administered to the patient. In some implementations, the user interface component can be adapted for selecting a meal of a known content.

Claims

1. A computer-implemented method of determining an assessed carbohydrate to insulin ratio (CIR_new) of a patient, the method being performed by execution of computer program instructions by one or more processors, the method, comprising:

receiving, by one or more processors, an initial set of values comprising at least a normoglycemia glucose level (BG₀). a target glucose level (TBG), an insulin sensitivity (IS), and, an estimated carbohydrate to insulin ratio (CIR_old);

receiving, by one or more processors, a Carb value representing a planned meal of a content having a known carbohydrate load (Carb);

receiving or determining, by one or more processors, a test bolus value based on the determined initial set of values and the Carb value;

receiving or determining, by one or more processors, a post-prandial glucose level (CBG) of the patient subsequent to administration of the test bolus and consumption of the planned meal;

determining, by one or more processors, the assessed carbohydrate to insulin ratio (CIR_new) of the patient based on the initial set of values and the post-prandial glucose level (CBG) of the patient;

wherein the determination of the post-prandial glucose level (CBG) is repeated, by one or more processors, until either;

a substantially constant glucose level (BG₁) is achieved, and/or

a normal post-prandial glucose level is achieved.

2. The computer-implemented method of claim 1, wherein if a difference between the normoglycemia glucose level value and the post-prandial glucose level value is within a predefined range, then the assessed carbohydrate to insulin ratio is determined to be substantially the same as the initial carbohydrate to insulin ratio of the patient.

3. The computer-implemented method of claim 1, wherein if a difference between the normoglycemia glucose level value and the post-prandial glucose level value does not fall within a predefined range, then the carbohydrate to insulin ratio is reassessed.

4. The computer-implemented method of claim 1, wherein if a difference in glucose values calculated by subtracting the normoglycemia blood glucose level value from the post-prandial glucose level value is less than a predefined absolute value, then the carbohydrate to insulin ratio is reassessed.

5. The computer-implemented method of claim 1, wherein the known meal content comprises carbohydrates with a relatively high glycemic index.

6. The computer-implemented method of claim 1 further comprising, if a difference in the glucose values calculated by subtracting the normoglycemia glucose level value from the post-prandial glucose level value is greater than a predefined value, advising the patient to administer a correction bolus.

7. The computer-implemented method of claim 1 further comprising, if a difference in the glucose values calculated by subtracting the post-prandial glucose level value from the normoglycemia glucose level value is greater than a predefined value, advising the patient to consume an amount of carbohydrates to achieve the target glucose level.

8. The computer-implemented method of claim 1, wherein prior to determining the initial set of values, the patient is required to fast for a period of time.

9. The computer-implemented method of claim 8, wherein the period of time is at least three hours.

10. The computer-implemented method of claim 1, wherein prior to determining the initial set of values, the patient is required to achieve normoglycemia.

11. The computer-implemented method of claim 1, wherein after the receiving a confirmation that the test bolus dosage has been administered to the patient and prior to the determining the assessed carbohydrate to insulin ratio, the patient is required to achieve normoglycemia.

12. The computer-implemented method of claim 11, wherein the determination of normoglycemia is made by comparing the post-prandial glucose level of the patient to the target glucose level.

13. The computer-implemented method of claim 11, wherein while the normoglycemia is not achieved, the patient is repetitively required to perform a glucose correction.

14. The computer-implemented method of claim 13, wherein the post-prandial glucose level of the patient is retested after each glucose correction.

15. The computer-implemented method of claim 13, wherein the glucose correction comprises at least one of the administering a correction bolus and consuming a correction glucose.

16. The computer-implemented method of claim 15, wherein the assessed carbohydrate to insulin ratio is determined based on the correction bolus.

17. The computer-implemented method of claim 15, wherein the assessed carbohydrate to insulin ratio is determined based on the correction glucose.

18. The computer-implemented method of claim 13, wherein the patient is repetitively required to perform the glucose correction during a predetermined period of time.

44. The method of claim 1, wherein if the substantially constant glucose level (BG₁) is achieved, the assessed carbohydrate to insulin ration (CIR_new) is calculated by one or more processors as:

19. A system for determining an assessed carbohydrate to insulin ratio (CIR_new) of a patient, comprising:

a memory component adapted for storing an initial set of values comprising at least a normoglycemia glucose level (BG₀), a target glucose level (TBG), an insulin sensitivity(IS), and, an estimated carbohydrate to insulin ratio (CIR_old);

a user interface component adapted for selecting a meal of a content having a known carbohydrate load (Carb);

a bolus selection component adapted for selecting a test bolus dosage based on the stored initial set of values and the planned meal;

a glucose sensing component adapted for periodically determining a post-prandial glucose level (CBG) of the patient subsequent to administration of the test bolus dosage and consumption of the planned meal; and

,

a CIR assessment component comprising one or more processors executing computer program instructions adapted for determining the assessed carbohydrate to insulin ratio (CIR_new) of the patient based on the initial set of values and the post-prandial glucose level value (CBG);

wherein the determination of the post-prandial glucose level (CBG) is repeated until either;

a substantially constant glucose level (BG₁) is achieved, and/or

a normal post-prandial glucose level is achieved.

20. The system of claim 19, wherein if a difference between the normoglycemia glucose level value and the post-prandial glucose level value is within a predefined range, then the assessed carbohydrate to insulin ratio is determined by one or more processors to be substantially the same as the initial carbohydrate to insulin ratio of the patient.

21. The system of claim 19, wherein if a difference between the normoglycemia glucose level value and the post-prandial glucose level value does not fall within a predefined range, then the carbohydrate to insulin ratio is reassessed.

22. The system of claim 19, wherein if a difference between the normoglycemia glucose level value and the post-prandial glucose level value is less than a predefined absolute value, then the assessed carbohydrate to insulin ratio is determined by one or more processors to be substantially the same as the initial carbohydrate to insulin ratio of the patient.

23. The system of claim 19, wherein the known meal content comprises carbohydrates with a relatively high glycemic index.

24. The system of claim 19 wherein, if a difference in the glucose values calculated, by one or more processors, by subtracting the normoglycemia glucose level value from the post-prandial glucose level value is greater than a predefined value, the user interface component is further adapted for advising the patient to administer a correction bolus.

25. The system of claim 19 wherein, if a difference in the glucose values calculated, by one or more processors, by subtracting the post-prandial glucose level value from the normoglycemia glucose level value is greater than a predefined value, the user interface component is further adapted for advising the patient to consume an amount of carbohydrates to achieve the target glucose level.

26. The system of claim 19, wherein the user interface component is adapted for advising the patient to fast for a period of time prior to determining the initial set of values.

27. The system of claim 26, wherein the period of time is at least three hours.

28. The system of claim 19, wherein the user interface component is further adapted for advising the patient to achieve normoglycemia prior to determining the initial set of values.

29. The system of claim 19, wherein the user interface component is further adapted for advising the patient to achieve normoglycemia after a confirmation that the test bolus dosage has been administered is received.

30. The system of claim 29, wherein the determination of normoglycemia is made by comparing the post-prandial glucose level of the patient to the target glucose level.

31. The system of claim 29, wherein while the normoglycemia is not achieved, the user interface component is adapted for repetitively requiring the patient to perform a glucose correction.

32. The system of claim 31, wherein the glucose sensing component retests the post-prandial glucose level of the patient after each glucose correction.

33. The system of claim 32, wherein the glucose correction comprises at least one of the administering a correction bolus and consuming a correction glucose.

34. The system of claim 33, wherein the assessed carbohydrate to insulin ratio is determined by one or more processors based on the correction bolus.

35. The system of claim 34, wherein the assessed carbohydrate to insulin ratio is determined by one or more processors based on the correction glucose.

36. The system of claim 33, wherein the user interface is further adapted for requiring the patient to perform the glucose correction during a predetermined period of time.

37. The system of claim 19 further comprising an insulin infusion component coupled to said glucose sensing component.

38. The system according to claim 37, wherein said insulin infusion component is configured as a patch unit adherable to the skin of the patient.

39. The system according to claim 38, further comprising a remote control unit configured to communicate with the patch unit and further configured to allow programming and data acquisition.

40. The system according to claim 39, wherein said CIR assessment component resides in the remote control unit.

41. The system of claim 19, wherein the glucose sensing component is a glucose monitor.

42. The system of claim 41, wherein the glucose monitor is a glucometer.

43. The system of claim 41, wherein the glucose monitor is a CGM.

45. The system of claim 19, wherein if the substantially constant glucose level (BG₁) is achieved, the assessed carbohydrate to insulin ration (CIR_new) is calculated by one or more processors as:

46. The system of claim 45, wherein the correction bolus (CB_i) needed when the post-prandial glucose level (CBG) is above the target glucose level (TBG) is calculated by one or more processors as follows: