Diabetes therapy Flashcards
Lifestyle goals for diabetes
Maintain healthy weight; Regular physical activity; Nutrition therapy: Consistent carbs, evenly spaced, Lower glycemic index foods (how quickly it’s absorbed); Smoking cessation
Glycemic targets
Fasting & pre-meal: 4-7 mmol/l; Post-prandial: 5-10 mmol/l; HbA1c < 7.0% for most (depends on context)
Type 1 diabetes goals
physiologic replacement of insulin: multiple daily injections (MDI) and continuous subcutaneous insulin infusion (CSII) (mimic normal; near-normal glycemia (don’t push it); minimize risk of hypoglycemia
Basal vs bolus insulin
Basal: long acting, prevent hepatic glucose production when fasting/sleeping, maintain fasting. Bolus: rapid, given with meals, promote glucose uptake
Where do we get Insulin?
No longer animals: produce human insulin in bacteria. Regular insulin = human insulin
Injecting insulin - what happens before it enters blood?
self associates as hexamer, but too big to get into blood. Go into dimers/monomers, then can. Takes about 30 mins to happen, so need to inject before meal
Rapid analogs of insulin
Switch two aa, which prevents insulin from self associating, so they stay as monomer as acts faster
When giving IV insulin, which type of insulin should you give?
Shouldn’t matter! The hexamer is only a problem when injecting, so no problem with IV
Insulin dosing - the 3 legged stool
- Insulin dose should match carbohydrate intake (based on the individual’s insulin sensitivity); 2. Exercise (recent or anticipated) reduces insulin requirements; 3. Extra insulin may be required to correct for high glucose levels. pt needs to think like a pancreas!
Insulin dosing - how much should be bolus and basal?
About 50/50. Basal for longterm, bolus with meals.
Meal-time insulin dosing
Roughly 1 unit/10g carbs. Correction factor: 1 unit/3mmol above target
Sliding scale and dosing
Not very good!! Only works for people who have just slightly high sugars. It often wouldn’t give insulin with meals if their sugars are low. Wrong! Pt with Type 1 would not do well on it. Try this scale
Complications of insulin therapy
weight gain; hypoglycemia; lipohypertrophy (fat deposits if you inject always the same spots - plus the insulin won’t get absorbed well there!); (lipoatrophy - only on old insulin); insulin allergy - usually uncommon but can happen
Absorption rate of insulin
Usually inject where there is subcutaneous fat - so basically anywhere. Areas with higher fat (gut, butt) will be slower. Heat (ie hot tub) increases vasculature, so absorption increases
Top 11 errors with Type 1 diabetes tx
Bolusing after meals, Lipohypertrophy, Overtreating Lows, Overtreating Highs, Sliding Scales, Too much basal / Too much bolus, Eating Disorders, Not adjusting for exercise, Fear of hypoglycemia, Missed boluses for meals/ snacks, Bolus insulin at bedtime
Type 2 diabetes current guidelines
If A1C <8.5: Start metformin, or encourage them to start exercising etc and then start metformin. If A1C ≥8.5: Start metformin and consider a combo, shoot for decrease of 1.5
Factors to consider for agent after metformin?
BG lowering efficacy & durability, Risk of inducing hypoglycemia, Effect on weight, Contraindications & side effects, Cost and coverage, Other
Drugs for type 2
Insulin: obvs. Metformin: helps insulin work better by affecting liver and increasing peripheral sensitivity. AGI: helps starch break down slower, but more starch goes to large intestine which can make gas. SU/glinides: secretagogues, stimulate ß cells for long time, risk hypoglycemia; … ; TZD: turn on/off genes to increase subcutaneous fat and increase sensitivity. SGLT2i(nhibitor): reduce absorption of glucose from urine, so more gets lost that way.
Metformin
helps insulin work better by affecting liver and increasing peripheral sensitivity. Safe, cheap, effective. Insulin Sensitiser; No hypoglycemia; Weight loss; Can be combined with insulin; GI side effects; Care required in CKD (can use if stable)
AGI
helps starch break down slower, but more starch goes to large intestine which can make gas. Prevents hyperglycaemia post-meal and no hypo. eg. Acarbose
SU/glinides
secretagogues, stimulate ß cells for long time, risk hypoglycemia. Stimulate insulin release while bypassing the glucose stimulus (affects K+ channel in ß cells). Glyburide (less safe), glyclazide (safe), glimepiride (not covered), repaglinide (take with food). Safe generally, cheap, effective, hypoglycemia and weight gain side effects.
TZD
Thiazolidinediones. Insulin sensitizers. turn on/off genes to increase subcutaneous fat and increase sensitivity. NOT combined with insulin. Expensive, weight gain, edema
SGLT2i(nhibitor)
affects an enzyme in the kidneys, thereby reducing absorption of glucose from urine, so more gets lost that way. No hypoglycemia; weight loss, lower BP; increases chance of genital/UTI. Requires high GFR to deliver glucose.
Incretins
gut hormones, respond to glucose in gut and stimulate insulin production. Lower glucagon release, promote satiety in brain, slows gastric emptying, enhance glucose-dependent insulin release. DPP inhibitors so these peptides don’t get broken down so fast. ‘-gliptins’
