Diabetes I and II

Question 1

Metformin

Answer 1

Decreases hepatic synthesis of glucose; no effect on circulating insulin levels

Benefits: Weight neutral, no risk of hypoglycemia when used as monotherapy

Adverse effects: GI upset (nausea, vomiting, bloating); contraindicated in patients with renal disease, metabolic acidosis, IV iodinated contrast, congestive heart failure

Question 2

Sulfonylureas

Answer 2

Increase endogenous insulin release by blocking the ATP-sensitive K+ channel on pancreatic beta cells

Adverse effects: Hypoglycemia, weight gain, GI upset
Contraindicated in: Sulfa allergies, G6PD deficiency, hepatic/renal disease

Question 3

Thiazolidinediones (TZDs)

Answer 3

Bind to the PPAR-y / RXR receptor on adipocytes; binding activates adiponectin, which increases expression of genes that control insulin sensitivity in adipose and skeletal muscle tissue

Adverse effects: Fluid retention / edema, hepatotoxicity
Contraindicated in patients with CHF, liver disease, or high CVD risk

Question 4

GLP-1 agonists

Answer 4

Potentiate glucose-stimulated (post prandial) insulin release and decrease post prandial glucagon

Benefits: Lowers A1c, increases satiety, induces weight loss

Adverse effects: Nausea, hypoglycemia when administered in combination with sulfonylureas; must be administered as SC injection

Question 5

DPP-4 Inhibitors

Answer 5

Block the action of DPP-4 leading to 2-3x increased circulating levels of endogenous GIP and GLP-1; main effect is to potentiate endogenous insulin secretion and decrease glucagon secretion

Benefits: Orally administered
Adverse effects: Nasopharyngitis, headache, ?Stevens-Johnson Syndrome, ?Acute pancreatitis

Question 6

Amylin analog

Answer 6

Normally, amylin is co-secreted with insulin from pancreatic B cells and functions to reduce food intake and induce weight loss; amylin levels are elevated in TIIDM suggesting amylin insensitivity

Amylin analog is administered before meals to patients on prandial insulin therapy

Benefits: Reduces food intake and induces weight loss
Drawbacks: SC injection and cannot be mixed with insulin, insulin-induced hypoglycemia, nausea/vomiting

Question 7

SGLT-2 Inhibitors

Answer 7

Blocks glucose reabsorption in the kidney leading to increased glucose excretion

Benefits: Weight loss, decreased BP
Adverse effects: GU infection, hypovolemia, hyperkalemia, impaired bone metabolism; contraindicated in patients with severe renal disease / dialysis

Question 8

Fasting glucose values

Answer 8

Normal: < 100
Pre-Diabetes: 101-125
Diabetes: > 126

Question 9

Impaired fasting glucose values

Answer 9

101-125

Question 10

2hour OGTT values

Answer 10

Normal: < 140
Pre-Diabetes: 141-199
Diabetes: > 200

Question 11

Impaired glucose tolerance values

Answer 11

141-199

Question 12

A1c values

Answer 12

Normal: < 5.7%
Pre-Diabetes: 5.8-6.4%
Diabetes > 6.5%

Question 13

Glycemic goals in diabetes management

Answer 13

A1c < 7%
Fasting glucose: 70-130
2hr post-prandial glucose: < 180

Question 14

Glargine (Lantus)

Answer 14

Long acting insulin used for basal therapy; lasts 24 hours with no prolonged peak, administered 1x/daily

*Cannot be mixed with other insulins due to acidity

Question 15

Detemir (Levemir)

Answer 15

Long acting insulin used for basal therapy; lasts 12-18 hours, administered 2x/day for basal coverage

Question 16

NPH Insulin

Answer 16

Intermediate-acting insulin used 2x/daily for basal therapy; lasts 12-16 hours, can be used to treat mid-day hyperglycemia associated with lunch, and can be mixed with other insulins

*Comes as a cloudy solution

Question 17

Regular insulin

Answer 17

Short acting, human recombinant insulin; effect lasts 6-8 hours

Not used in outpatient management of diabetes; given as IV infusion to treat DKA inpatient

Question 18

Rapid-acting insulin analogs

Answer 18

Humalog, Novolog, Glulisine

Absorbed rapidly by SC injection; effect peaks at 1-1.5 hours and lasts 3-5 hours; administered immediately before meals for control of post-prandial hyperglycemia

Can be administered in the same syringe as NPH insulin for combination basal/bolus therapy; can be used with insulin infusion devices

Question 19

Mixed insulin

Answer 19

Rapid acting insulin analog + NPH; can be used as combination basal-bolus therapy, often injected 2x/day before breakfast and dinner; comes in several preparations:

75% NPH / 25% Humalog
70% NPH / 30% Humalog
50% NPH / 50% Humalog

Question 20

What formula estimates a starting dose for basal insulin?

Answer 20

0.2 units / kg / day

Question 21

How is the correction factor calculated?

Answer 21

1600 / total daily dose of insulin

This gives the amount (g/dL) that blood glucose should decrease in response to 1 unit of insulin; individuals with greater insulin insensitivity will have a lower correction factor

Question 22

What is the Dawn phenomenon?

Answer 22

Early morning hyperglycemia in response to surging growth hormone and/or cortisol

Question 23

Indications for insulin therapy in type 2 DM

Answer 23

Signs of severe insulin deficiency: fasting glucose > 250, random glucose > 300, A1c > 10%, weight loss

Hospitalization for hyperglycemic hyperosmolar state, or diabetic ketoacidosis

Patients should be maintained on insulin for several months outpatient; may be tapered and switched to non-insulin therapy eventually