System and method for determining insulin bolus quantities

• US 20060137695A1
• Filed: 12/23/2004
• Published: 06/29/2006
• Est. Priority Date: 12/23/2004
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics International AG (Roche Holding AG)
• Inventors: Weinert, Stefan, Hellwig, Robert
• Granted Patent: US 7,869,851 B2
• Time in Patent Office: Days
• US Class Current: 128/898
• CPC Class Codes: A61M 2005/1405 Patient controlled analgesia [PCA]
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 5/1413 Modular systems comprising interconnecting elements
• CPC Class Codes: G01N 2333/4745 Insulin-like growth factor binding protein
• CPC Class Codes: G01N 2800/042 Disorders of carbohydrate metabolism, e.g. diabetes, glucose metabolism
• CPC Class Codes: G01N 33/66 involving blood sugars, e.g. galactose
• CPC Class Codes: G01N 33/74 involving hormones or other non-cytokine intercellular protein regulatory factors such as growth factors, including receptors to hormones and growth factors
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

A method of computing an insulin bolus quantity when a measured glucose value in a current time interval exceeds a target glucose value for the current time interval and when a time duration of glucose lowering action of the bolus to be administered spans the current and a number of the next adjacent time intervals, may comprise determining a corresponding number of percentages of insulin action of the recommended bolus quantity that will each be used lowering the glucose level during a respective one of the number of time intervals, and computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for a last one of the number of next adjacent time intervals, the insulin sensitivities for the current and each of the number of next adjacent time intervals, and the corresponding number of percentages.

Claims

1. With a diabetes care system having a number of adjacent time intervals each defining an associated target glucose value and an insulin sensitivity value, a method of computing a recommended insulin bolus quantity when a measured glucose value in a current time interval exceeds the target glucose value for the current time interval and when a time duration of glucose lowering action of the recommended insulin bolus quantity to be administered spans the current time interval and a number of next adjacent time intervals, the method comprising the steps of:

determining a corresponding number of percentages each corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during a respective one of the number of time intervals between the current time interval and the number of next adjacent time intervals, and

computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for a last one of the number of next adjacent time intervals, the insulin sensitivities for the current and each of the number of next adjacent time intervals, and the corresponding number of percentages.

2. The method of claim 1 wherein the number of next adjacent time intervals is one,

and wherein the step of determining a corresponding number of percentages includes:

determining a first percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the current time interval,

determining a second percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the next time interval,

and wherein the computing step includes computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for the next adjacent time interval, the insulin sensitivities for the current and next adjacent time intervals, and the first and second percentages.

3. The method of claim 2 wherein the step of determining a first percentage includes determining the first percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

4. The method of claim 3 further including the step of computing a current interval bolus activity time as a difference between the beginning time of the next adjacent time interval and the current time,

and wherein the step of determining a first percentage includes determining the first percentage as a function of the current interval bolus activity time and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

5. The method of claim 4 wherein the step of determining a first percentage includes extracting the first percentage value from a table populated with first percentage values as functions of current interval bolus activity time values and time duration values of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

6. The method of claim 3 wherein the step of determining a second percentage includes computing the second percentage as a difference between one hundred percent and the first percentage.

7. The method of claim 2 wherein the step of determining a second percentage includes determining the second percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

8. The method of claim 7 further including the step of computing a next interval bolus activity time as a difference between the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity and a current interval bolus activity time corresponding to a difference between the beginning time of the next adjacent time interval and the current time,

and wherein the step of determining a second percentage includes determining the second percentage as a function of the next interval bolus activity time and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

9. The method of claim 8 wherein the step of determining a second percentage includes extracting the second percentage value from a table populated with second percentage values as functions of next interval bolus activity time values and time duration values of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

10. The method of claim 7 wherein the step of determining a first percentage includes computing the first percentage as a difference between one hundred percent and the second percentage.

11. The method of claim 2 further including the step of executing both determining steps and the computing step only if the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity extends into the next adjacent time interval by a predefined time amount.

12. With a diabetes care system having a number of adjacent time intervals each defining an associated target glucose value and an insulin sensitivity value, a method of computing a recommended insulin bolus quantity when a measured glucose value in a current one of the time intervals exceeds the target glucose value for the current time interval, the method comprising:

determining whether a time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity spans the current time interval and at least a next adjacent time interval, and

computing the recommended bolus quantity as a function of the measured glucose value, the target glucose value for the current time interval and the insulin sensitivity value for the current time interval only if the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity is confined to the current time interval.

13. The method of claim 12 further including the following steps if the time duration of the glucose lowering action of the subsequently administered recommended insulin bolus quantity otherwise spans the current time interval and a number of the next adjacent time interval:

determining a corresponding number of percentages each corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during a respective one of the number of time intervals between the current time interval and the number of next adjacent time intervals, and

computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for a last one of the number of next adjacent time intervals, the insulin sensitivities for the current and each of the number of next adjacent time intervals, and the corresponding number of percentages.

14. The method of claim 13 wherein the number of next adjacent time intervals is one,

and wherein the step of determining a corresponding number of percentages includes:

determining a first percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the current time interval,

determining a second percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the next time interval,

and wherein the computing step includes computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for the next adjacent time interval, the insulin sensitivities for the current and next adjacent time intervals, and the first and second percentages.

15. The method of claim 14 wherein the step of determining a first percentage includes determining the first percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

16. The method of claim 15 wherein the step of determining a second percentage includes computing the second percentage as a difference between one hundred percent and the first percentage.

17. The method of claim 14 wherein the step of determining a second percentage includes determining the second percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

18. The method of claim 17 wherein the step of determining a first percentage includes computing the first percentage as a difference between one hundred percent and the second percentage.

19. The method of claim 14 further including the step of executing the steps of determining the first and second percentages and the step of computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for the next adjacent time interval, the insulin sensitivities for the current and next adjacent time intervals, and the first and second percentages only if the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity extends into the next adjacent time interval by a predefined time amount.

20. With a diabetes care system having a number of adjacent time intervals each defining an associated target glucose value and an insulin sensitivity value, a method of computing a recommended insulin bolus quantity when a measured glucose value in a current one of the time intervals exceeds the target glucose value for the current time interval and when a time duration of glucose lowering action of the recommended insulin bolus quantity to be administered spans the current time interval and the next adjacent time interval, the method comprising:

determining a first difference as a difference between the target glucose value for the current time interval and the target glucose value for the next adjacent time interval,

determining a second difference as a difference between the insulin sensitivity value for the current time interval and the insulin sensitivity value for the next adjacent time interval, and

computing the recommended bolus quantity as a function of the measured glucose value, the target glucose value for the current time interval and the insulin sensitivity value for the current time interval only if the first difference is less than a first threshold value and the second difference is less than a second threshold value.

21. The method of claim 20 further including the following steps if either of the first difference exceeds the first threshold value and the second difference exceeds the second threshold value:

determining a first percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the current time interval,

determining a second percentage corresponding to a percentage of insulin action of the recommended bolus quantity that will be used lowering the glucose level during the next time interval, and

computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for the next adjacent time interval, the insulin sensitivities for the current and next adjacent time intervals, and the first and second percentages.

22. The method of claim 21 wherein the step of determining a first percentage includes determining the first percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

23. The method of claim 22 wherein the step of determining a second percentage includes computing the second percentage as a difference between one hundred percent and the first percentage.

24. The method of claim 21 wherein the step of determining a second percentage includes determining the second percentage as a function of at least a current time in the current time interval at which the measured bolus value was measured, a beginning time of the next adjacent time interval and the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity.

25. The method of claim 24 wherein the step of determining a first percentage includes computing the first percentage as a difference between one hundred percent and the second percentage.

26. The method of claim 21 further including the step of executing the steps of determining the first and second percentages and the step of computing the recommended bolus quantity as a function of the measured glucose value, the target blood glucose level for the next adjacent time interval, the insulin sensitivities for the current and next adjacent time intervals, and the first and second percentages only if the time duration of glucose lowering action of the subsequently administered recommended insulin bolus quantity extends into the next adjacent time interval by a predefined time amount.