Insulin

Question 1

What is normal daily insulin secretion in healthy, nonpregnant adults without obesity?

Answer 1

0.5-0.7 units per kg of BW

Question 2

What are the mechanisms of action for insulin?

Answer 2

-stimulates entry of AA into cells/enhances protein synthesis
-enhances fat storage (lipogenesis) & prevents mobilization of fat for energy (lipolysis and ketogenesis)
-stimulates entry of glucose into cells for use as energy source/promotes storage of glucose as glycogen (glycogenesis) in muscle and liver cells
=inhibits production of glucose from liver/muscle glycogen (glycogenolysis)
-Inhibits formation of glucose from non CHO, such as AA (gluconeogenesis)

Question 3

What are the counterregulatory hormones to insulin?

Answer 3

glucagon, epinephrine, norepinephrine, growth hormone, and cortisol

Question 4

What are the concentrations of insulin currently available in the US?

Answer 4

U-100, U-200, U-300, and U-500, indicating 100 units/mL, 200 units/mL, etc

Question 5

How are insulin products classified?

Answer 5

according to onset, peak effect, and duration of action

Question 6

What are the currently available rapid acting insulin products?

Answer 6

lispro, aspart, glulisine, afrezza

Question 7

What is the current available short acting insulin?

Answer 7

regular insulin

Question 8

What is rapid acting insulin usually preferred to regular insulin for post prandial coverage?

Answer 8

b/c of very rapid onset and short duration of action (reduced risk of late onset hyperglycemia d/t its longer duration of action)

Question 9

When should rapid acting insulin be administered?

Answer 9

Immediately prior to eating (<15 mins preprandially); injecting too early (30-60 mins before meals may result in profound hypoglycemia

Question 10

What does NPH stand for?

Answer 10

Neutral protamine Hagedorn (named for the researcher who derived the formulation)

Question 11

What are the long acting insulin analogs?

Answer 11

Lantus, determir, and degludec

Question 12

When converting pt from NPH to glargine, how much should the glargine be reduced by?

Answer 12

Reduce glargine dose to 80% of previous NPH dose to avoid filling the previous glycemic “valley” with insulin and inducing hypoglycemia

Question 13

Can insulin detemir be diluted or mixed with any other insulin preperations?

Answer 13

No

Question 14

What are the commercially available premixed insulin products?

Answer 14

70/30, 50/50, and 75/25

May be appropriate for pt’s with DM who have difficulty mixing their own insulin, or those who do not want to commit to a strict basal/bolus regimen

Question 15

What are the two fixed dose combo of basal insulin with GLP-1 RA

Answer 15

Insulin glargine/lixiseatide and degludec/liraglutide

Inclusion of a GLP-1 RA w/ basal insulin offers similar glycemic control, but is less likely to cause weight gain

Question 16

When building an insulin regimen, what factors should be considered?

Answer 16

type of DM, clinical assessment of insulin deficiency and suspected insulin resistance and individual preference (eating times, meal comp, exercise, waking/sleeping patterns), A1c levels, wt/lipid goals, and variablity of lifestyle/activities

Question 17

What is a “starting “dose of long acting insulin for a patient with DM2 also taking 1 or more oral agents

Answer 17

10 units or 0.2 units per kg administered in the morning or at bedtime

Question 18

Per AACE algorithim, what is the starting dose recommendation for long acting insulin (in units per kg)

Answer 18

A1c < 8.0: 0.1-0.2 units per kg

A1c > 8%: 0.3-0.4 units per kg

Question 19

Regardless of starting dose, how should insulin increases be made?

Answer 19

Every 2-3 days in fixed increments (2-4 units) or as a percentage of the current dose (10-20%)

Due the presence of insulin resistance in DM2, the ultimate TDD of basal insulin is often very high (usually 0.5 units per kg per day but may range from 0.7-2.5 units per kg per day)

Question 20

What are the most three commonly used approaches when insulin is used to treat DM2 as the sole source of glycemic control?

Answer 20

1. twice daily intermediate insulin
2. split-mixed insulin (2/3rd of TDD is given before breakfast–1 part rapid/short acting to 2 parts intermediate) and 1/3rd is given before evening meal (using ratio of 1:1 or 1:2)
3. semi intensive insulin (combines 1 dose long acting with i dose rapid acting with the largest meal)

Question 21

when adding rapid acting insulin for prandial coverage of the largest meal, what is the recommended dose for insulin?

Answer 21

0.1 unit per kg or 10% of the basal dose, or 4-5 units

Subsequent adjustments of rapid acting can be made based on 1 our PPBG by either 1-2 units or 10-15% of the dose

If hypogycemia, determine cause and if consistent, reduce rapid acting by 2-4 units or 10-20%

Question 22

What is the goal of insulin therapy in DM1?

Answer 22

To mimic (as close as possible) the physiologic profile of insulin secretion (basal/bolus)

Question 23

Physiologic insulin secretion typically occurs at a rate of __ to ___ units per hour

Answer 23

0.5-1.0

Question 24

What are insulin requirements for pt’s with DM1 who are w/in 20% of their IBW?

Answer 24

0.5-1.0 units per kg of body weight per day

Question 25

What are insulin requirements for a type 1 DM patient during the “honeymoon phase”

Answer 25

0.2-0.6 units per kg per day

Question 26

What is considered the standard of care for insulin delivery in a patient with DM1?

Answer 26

Insulin infusion via insulin pump

Question 27

What happens with insulin requirements for a pregnant women with preexisting DM?

Answer 27

Requirements increase early in pregnancy followed by decrease in weeks 9-16

During 2-3 trimester, insulin resistance gradually increased by ~5% per week and may result in insulin demands of 0.9-1.2 units per kg per day (as much as twice the TDD of insulin needed before pregnancy)

Question 28

Why do insulin requirements increase during the 2nd and 3rd trimester of pregnancy for a patient with preexisting DM?

Answer 28

Placental production of counterregulatory hormones which diminish responsiveness to insulin action

Women should be treated w/ intensive regimen, 3-4 injections or an insulin pump to provide basal/bolus regimen

Question 29

Where should pregnancy women be counseled to inject their insulin?

Answer 29

Thigh or back of arm