INSULIN DELIVERY SYSTEM AND METHODS WITH RISK BASED SET POINTS

• US 20170332952A1
• Filed: 05/22/2017
• Published: 11/23/2017
• Est. Priority Date: 05/23/2016
• Status: Active Application

• Current Assignee: Insulet Corporation
• Original Assignee: Bigfoot Biomedical, Inc.
• Inventors: Desborough, Lane, Mazlish, Bryan
• Application Number:
  US15/601,282
• Publication Number:
  US 20170332952A1
• Time in Patent Office: Days
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61M 2005/14268 with a reusable and a disposable component
• CPC Class Codes: A61M 2005/14296 Pharmacokinetic models
• CPC Class Codes: A61M 2205/3569 sublocal, e.g. between console and disposable
• CPC Class Codes: A61M 2205/3584 using modem, internet or bluetooth
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/003 Kits for diabetics
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• 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: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 40/63 : for local operation

Abstract

A method may include obtaining blood glucose level readings over a diurnal period for each of a plurality of days and determining an estimated variability of the blood glucose levels over the diurnal period for the plurality of days. The method may also include modifying, based on the estimated variability of the blood glucose level, a target blood glucose level to a modified target blood glucose level, and delivering insulin, using an insulin pump, during the diurnal period based on the modified target blood glucose level.

Claims

1. A method comprising:

obtaining blood glucose level readings over a diurnal period for each of a plurality of days;

determining an estimated variability of the blood glucose levels over the diurnal period for the plurality of days;

modifying, based on the estimated variability of the blood glucose level, a target blood glucose level to a modified target blood glucose level; and

delivering insulin, using an insulin pump, during the diurnal period based on the modified target blood glucose level.

2. The method of claim 1, wherein determining the variability comprises determining a measure of dispersion for blood glucose values for the diurnal period and determining an approximate percentage of blood glucose measurements expected to fall below a threshold blood glucose level.

3. The method of claim 2, wherein modifying comprises incrementally increasing the target blood glucose level if the determined approximate percentage exceeds a threshold percentage, with the provision that the target blood glucose level may be capped at a maximum target blood glucose level.

4. The method of claim 3, wherein the threshold percentage is determined by a fear of hypoglycemia index (FHI) set by a user.

5. The method of claim 3, wherein the increase in the diurnal target blood glucose level is determined by determining a diurnal measure of central tendency and a diurnal measure of dispersion for blood glucose values and determining a shift to the diurnal target blood glucose level that would approximately achieve the threshold percentage of the blood glucose values being below the threshold blood glucose level

6. The method of claim 2, wherein the target blood glucose level is capped at a maximum target blood glucose level.

7. The method of claim 2, wherein modifying comprises incrementally decreasing the target blood glucose level if the determined approximate percentage is less than a threshold percentage, with the provision that the target blood glucose level may be limited by a minimum target blood glucose level.

8. The method of claim 7, wherein the target blood glucose level is limited by a minimum target blood glucose level.

9. The method of claim 7, wherein the threshold percentage is determined by a fear of hypoglycemia index (FHI) set by a user.

10. The method of claim 7, wherein the decrease in the diurnal target blood glucose level is determined by determining a diurnal measure of central tendency and a diurnal measure of dispersion for blood glucose values and determining a shift to the diurnal target blood glucose level that would approximately achieve the threshold percentage of the blood glucose values being below the threshold blood glucose level

11. The method of claim 10, wherein the target blood glucose value is decreased by no more than 2 mg/dL per day.

12. The method of claim 1, wherein modifying the diurnal period further includes modifying an adjacent diurnal period in the same direction to smooth changes in target blood glucose targets between diurnal periods.

13. The method of claim 1, wherein delivering insulin during the diurnal time period based on the modified target blood glucose level includes:

generating a first plurality of insulin delivery profiles, each of the first plurality of insulin delivery profiles including a first series of insulin delivery actions spanning a first time interval extending over the diurnal period and subsequent diurnal periods;

projecting a first plurality of future blood glucose values for each insulin delivery profile of the first plurality of insulin delivery profiles for a plurality of times spanning the first time interval, each projected future blood glucose values being projected using at least one up-to-date blood glucose level for a person with diabetes (PWD);

selecting a first profile of the first plurality of insulin delivery profiles based at least in part upon a comparison between the first plurality of future blood glucose values for each insulin delivery profile and a plurality of modified target blood glucose levels for each diurnal period overlapping with the first time interval;

delivering a first dose of insulin using an insulin pump for a second time interval after a previous dose of insulin, the first dose of insulin corresponding to a first action in the first series of insulin delivery actions of the first profile, the second time interval being equal to or shorter than the diurnal period.

14. The method of claim 1, wherein determining an estimated rate of variability in the blood glucose levels over the diurnal period for the plurality of days includes weighting blood glucose levels from more recent days of the plurality of days more heavily than blood glucose levels from older days of the plurality of days.

15. The method of claim 1, wherein determining an estimated rate of variability in the blood glucose levels over the diurnal period for the plurality of days includes excluding from the plurality of days blood glucose levels from days older than a cutoff date.

16. A system comprising:

a glucose sensor configured to generate blood glucose level readings;

an insulin pump configured to deliver insulin based on a message;

a control device configured to;

obtain blood glucose level readings over a diurnal period for each of a plurality of days;

determine an estimated variability in the blood glucose levels over the diurnal period for the plurality of days;

modify, based on the estimated variability in the blood glucose level, a target blood glucose level to a modified target blood glucose level; and

generate a message to deliver insulin during the diurnal period based on the modified target blood glucose level.

17. The system of claim 16, wherein the control device is one of a mobile computing device, a remote server, and control circuitry.

18. The system of claim 17, wherein the message includes instructions to control circuitry to utilize the modified target blood glucose level in controlling delivery of insulin.

19. The system of claim 16, wherein the glucose sensor includes a continuous glucose monitor (CGM).

20. A non-transitory computer readable medium containing instructions that, when executed by a processor, are configured to perform operations, the operations comprising:

obtaining blood glucose level readings over a diurnal period for each of a plurality of days;

determining an estimated variability in the blood glucose levels over the diurnal period for the plurality of days;

modifying, based on the estimated variability in the blood glucose level, a target blood glucose level to a modified target blood glucose level; and

generating a message to deliver insulin during the diurnal period based on the modified target blood glucose level.