Adaptation of automatic insulin delivery (AID) for users with basal to bolus mismatch
Exemplary embodiments provide more customized basal insulin amounts for users to better regulate blood glucose (BG) concentration levels. The exemplary embodiments do not statically assume that the daily basal amount for each user is 50% of TDI. Instead, actual TDI data may be gathered for each user and may be used to adjust the TDI value for that user to an updated value. In addition, the ratio of basal to TDI may be adjusted for the user based on the actual ratio determined from data gathered over one or more days. As a result, better BG concentration level control may be realized.
1 . An insulin delivery device, comprising:
a pump for pumping insulin to a user;
a processor for controlling delivery of basal insulin to the user via the pump, the processor configured for performing the following:
establishing an initial current basal amount of insulin to be delivered to the user per a time period of up to a day as a portion of an estimated total daily insulin (TDI) for the user;
determining an average of actual TDIs for the user over a period of days, wherein the actual TDI for each day in the period of days is a sum of basal insulin and bolus insulin delivered for the day;
determining a new TDI value from the average of the actual TDIs for the user over the period of days;
determining a ratio of basal insulin delivered to the user over the period of days relative to the actual TDIs of the user for the days of the period of days; and
adapting the initial current basal amount of insulin to be delivered to the user for the time period to a new basal amount based on a product of the ratio and the new TDI value for the user.
2 . The insulin delivery device of claim 1 , wherein the time period is a day and wherein the initial current basal amount to be delivered to the user for the time period is established as half of the estimated TDI for the user.
3 . The insulin delivery device of claim 1 , wherein the adapting the initial current basal amount of insulin to be delivered to the user per the time period comprises updating the new basal amount of insulin to be delivered per the time period to decrease a difference between the initial current basal amount of insulin to be delivered to the user per the time period and a fraction of the average actual TDI for the user over the period of days.
4 . The insulin delivery device of claim 3 , wherein how much the difference between the initial current basal amount of insulin to be delivered to the user per the time period and the fraction of the average actual TDI for the user over the period of days is decreased depends on how many days are in the period of days.
5 . The insulin delivery system of claim 3 , wherein how much the difference between the initial current basal amount of insulin to be delivered to the user per the time period and the fraction of the average actual TDI for the user over the period of days is decreased depends on a weighting factor.
6 . The insulin delivery system of claim 1 , wherein the processor is further configured for performing:
extending the period of days by an additional day;
determining an average actual TDI for the user over the extended period of days; and
updating the adapted current basal amount of insulin to be delivered for the user per the time period to an updated amount as a fractional value of the average actual TDI for the user over the extended period of days.
7 . The insulin delivery system of claim 6 , wherein the time period is an hour and wherein the updating of the adapted current basal amount to be delivered to the user for the time period to a new basal amount comprises calculating the new basal amount b updated as
b
updated
=
S
·
TDI
new
24
TDI
new
=
(
1
-
X
·
N
days
)
TDI
old
+
X
·
N
days
I
total
where N days is a number of days in the period of days, TDI old is the estimated TDI for the user, S is the ratio, and TDI new is the determined new TDI value, X is an adaptivity factor that can range from 0 to 1.
8 . The insulin delivery system of claim 7 , wherein S is a constant.
9 . The insulin delivery system of claim 7 , wherein S is a variable with a value based on the ratio.
10 . The insulin delivery system of claim 1 , wherein the current basal amount is an amount per hour and wherein the adapting of the current basal amount to be delivered to the user to a new basal amount comprises calculating the new basal amount b new as
b
new
=
S
·
TDI
new
24
TDI
new
=
(
1
-
X
·
N
days
)
TDI
old
+
X
·
N
days
I
total
where N days is a number of days in the period of days, TDI old is the estimated TDI for the user, S is the ratio, and TDI new is the new TDI value.
11 . The insulin delivery system of claim 10 , wherein S has a value of S new , which is determined as:
S
new
=
(
1
-
X
·
N
days
)
S
old
+
X
·
N
days
I
basal
I
total
where S new is a newly calculated value of S, S old is a most recent value for S, I basal is an amount of basal insulin delivered for the period of days and I total is a total amount of insulin delivered to the user for the period of days.
12 . A method, comprising:
with a processor of an electronic device, establishing an initial current basal amount of insulin to be delivered to the user per a time period of up to a day as a portion of an estimated total daily insulin (TDI) for the user;
with the processor of the electronic device, determining an average actual TDI for the user over a period of days, wherein the average actual TDI for each day in the period of days is a sum of basal insulin and bolus insulin delivered for the day;
with the processor of the electronic device, determining a new TDI value from the average of the actual TDIs for the user over the period of days;
with the processor of the electronic device, determining a ratio of basal insulin delivered to the user over the period of days relative to the actual TDIs of the user for the days of the period of days; and
with the processor of the electronic device, adapting the initial current basal amount of insulin to be delivered to the user for the time period to a new basal amount based on a product of the ratio and the new TDI value for the user.
13 . The method of claim 12 , wherein the electronic device is an insulin delivery device.
14 . The method of claim 12 , wherein the time period is a day and wherein the initial current basal amount to be delivered to the user for the time period is established as half of the estimated TDI for the user.
15 . The method of claim 12 , wherein the adapting the initial current basal amount of insulin to be delivered to the user per the time period comprises decreasing a difference between the initial current basal amount of insulin to be delivered to the user per the time period and a fraction of the average actual TDI for the user over the period of days.
16 . The method of claim 15 , wherein how much the difference between the initial current basal amount of insulin to be delivered to the user per the time period and the fraction of the average actual TDI for the user over the period of days is decreased depends on how many days are in the period of days.
17 . The method of claim 15 , wherein how much the difference between the initial current basal amount of insulin to be delivered to the user per the time period and the fraction of the average actual TDI for the user over the period of days is decreased depends on a weighting factor.
18 . The method of claim 12 , further comprising:
extending the period of days by an additional day;
determining an average actual TDI for the user over the extended period of days; and
updating the adapted current basal amount of insulin to be delivered for the user per the time period to an updated amount as a fractional value of the average actual TDI for the user over the extended period of days.
19 . The method of claim 18 , wherein the time period is an hour and wherein the updating of the adapted current basal amount to be delivered to the user for the time period to a new basal amount comprises calculating the new basal amount b updated as
b
updated
=
S
·
TDI
new
24
TDI
new
=
(
1
-
X
·
N
days
)
TDI
old
+
X
·
N
days
I
total
where N days is a number of days in the period of days, TDI old is the estimated TDI for the user, S is the ratio, and TDI new is the new TDI value.
20 . An insulin delivery device, comprising:
a pump for pumping insulin to a user;
a processor for controlling delivery of basal insulin to the user via the pump, the processor configured for performing the following:
establishing a current basal amount of insulin to be delivered to the user per hour;
determining an average actual TDI for the user over a period of days, wherein the average actual TDI for each day in the period of days is a sum of basal insulin and bolus insulin delivered for the day;
determining a new value of a desired ratio of basal insulin per hour to an hourly portion of total daily insulin, designated as S new , as:
S
new
=
(
1
-
X
·
N
days
)
S
old
+
X
·
N
days
·
(
I
basal
I
total
+
0.5
)
2
where N days is a number of days in the period of days, S old is most recent value of a desired ratio of basal insulin per hour to an hourly portion of total daily insulin, I basal is an amount of basal insulin delivered for the period of days and I total is a total amount of insulin delivered to the user for the period of days; and
adapting the current basal amount of insulin to be delivered to the user for the time period from the initial current basal amount to a new basal amount b new as:
b
new
=
S
·
TDI
new
24
TDI
new
=
(
1
-
X
·
N
days
)
TDI
old
+
X
·
N
days
I
total
where Sis S new and TDI old a is a most recent estimate or actual TDI value for the user.