DIABETES Flashcards
diabetes is mainly caused by _____
hyperglycemia
3 causes of hyperglycemia (insulin related)
- impairment of insulin secretion
- defective insulin action (producing insulin but its not working)
- both
common complications related to diabetes
- loss of sensation
- poor blood circulation
- poor wound healing
- heart disease
- leads to blindess
- kidney diseases
epidemiology of diabetes
5-10% of canadians have type 1 - most onset <25 years
90-95% of canadians have type 2 - most onset > 24
Prevalence increases with age
Higher prevalence in males than females
where are alpha and beta cells secreted from and what do they secrete
from the pancreas
- beta = insulin
- alpha = glucagon
what is c-peptide
- Insulin secreted as a pre hormone that needs to be activated (connected by c-peptide)
- When insulin is activated - c-peptide is released (1:1 ratio)
- Useful to differentiate between the two types of diabetes
how to differentiate T1DM and T2DM with c-peptide
- Type 1: does not produce insulin - low/no c-peptide
- Type 2: usually have high secretion of insulin - high c-peptide levels
what is normal blood glucose levels
3.9-6.1 mmol/L
explain what happens to blood glucose levels and organs that are relevant after eating a meal
- After a meal, increase levels of blood glucose which will trigger insulin secretion from the pancreas and this will trigger the uptake of glucose in our tissues and muscles
- Return blood glucose back to normal
- Increase of insulin will also increase glycogenesis (synthesis of glycogen) and decreasing gluconeogenesis (synthesis of glucose from precursors that are not carbs)
which organs have glycogen and which one contributes to the maintenance of blood glucose levels
liver and muscles
- liver contributes to maintenance of blood glucose levels
explain what happens to blood glucose levels and organs that are relevant when fasting
- If normal blood glucose levels are dropping (fasting or overnight), trigger secretion from alpha pancreatic cells to secrete glucagon
- Inhibit glycogenesis (synthesis of glycogen) and increase gluconeogenesis (making carbs from non carb precursors)
- Sends glucose to our blood
describe the molecular process of insulin
insulin binds to insulin receptor - triggers a chain of reactions
- finishes with translocation of GLUT4 to the membrane which lets glucose enter
- insulin itself DOES NOT directly uptake glucose into cells
describe T1DM
- autoimmune response that destroys beta cells and then this impacts the ability to synthesize insulin
- autoimmune destruction of beta cells - caused by genetic + environmental + immune regulation
- patients will not produce insulin
- 90-95% of beta cells are destructed - some insulin produced but not nearly enough
describe T2DM
- combination of abnormal insulin secretion + insulin resistance
- individuals with T2DM produce insulin but their tissues are insulin resistant –> increases the need for insulin –> pancreas increases production –> over time, the pancreas is not able to maintain such high production levels
primary factors that “cause” T2DM
- obesity - central adiposity increases the degree of insulin resistance
- poor nutrition
- physical inactivity (activity seems to enhance whole-body insulin sensitivity
what is A1C
glycated hemoglobin - 3 month average
- expect high levels of A1C for those who have poor glycemic control
what is fasting glucose
blood sugar levels after fasting (8+ hours
what is random glucose
blood sugar levels anytime, no fasting
what is the A1C level to diagnose adults
A1C > or equal to 6.5
how are hyperglycemia and hydration/hunger related
- threshold until the kidneys cannot filter glucose anymore so you start losing glucose in the urine (glucoseurea)
- glucose is an osmotic active - draws water - leads to an increase of water in urine and this will increase urinary output (polyuria)
- decrease uptake of glucose by cels will lead to intracellular glucose deficiency that leads to polyphagia (hunger)
what are the three criteria of hypoglycemia and what mmol/L is the range
- development of neurogenic or neuroglycopenic symptoms
- low blood glucose (<4 mmol/L)
- symptoms respond to the administration of carbohydrate
what are some causes of hypoglycemia
- more physical activity than usual
- not eating on time
- eating less than planned
- taking too much medication
- alcohol (inhibits gluconeogenesis and inhibits glycogenolysis)
what is the treatment for mild-to-moderate hypoglycemia
- recognize symptoms
- confirm if possible (blood glucose < 4mmol/L)
- treat with “fast acting sugar” (15g)
- retest in 15 min to ensure BG >4mmol/L and retreat if needed
- eat snack/meal at usual time of day
what is the treatment for severe hypoglycemia (conscious person)
- Treat with oral fast-acting sugar
- Test after 15 min, if BG < 4mmol/L give them another 15g
- Once the hypoglycemia has been reversed, usual meal or snack that is due at that time
what is the treatment for severe hypoglycemia (unconscious person)
- With no intravenous access: 1mg glucagon given subcutaneously or intramuscularly
- Call 911
- With intravenous access: 10-25g of glucose should be given intravenously over 1-3 min
what is diabetes ketoacidosis and which DM is it more common in?
type 1
- When increase lypolysis (breakdown of fat) happens with no insulin present, this produces ketones that may lead to diabetes ketoacidosis
- Type 1 - no insulin present - increase lipolysis which will lead to formation of ketone bodies
- Formation of ketone bodies will decrease blood pH leading to acidosis
- With the presence of minimal insulin - this does not produce ketones - therefore diabetes ketoacidosis is not as prevalent in type 2 diabetes unless you are in the very late stages
what is hyperglycemic hyperosmolar syndrome and which DM is it more common in?
In type 2, hyperglycemia will lead to increase urinary output that will lead to electrolyte imbalance, dehydration, osmotic diuresis and this will lead to this syndrome
what is the treatment for hyperglycemic emergencies
- insulin, IV fluids, electrolyte replacement, sodium bicarbonate
what is the dawn phenomenon and what is the treatment
- Abnormal early morning increase in blood sugar (between 4-8am)
- More common in type I DM than type 2
- Mechanism: increase in hepatic glucose production, which may be secondary to the midnight surge of growth hormone
treatment:
- adjust insulin dosages
- adjustment of bedtime snack
what is somogyi effect and what is the treatment
- Early morning hyperglycemia occurs due to a rebound effect from late-night hypoglycemia
- Mechanism: counterregulatory hormones stimulate gluconeogenesis
treatment:
- adjust insulin levels
- adjust bedtime snack
how do you differentiate between dawn phenomenon and somogyi effect?
- wake up between 2-4am and monitor BGL
- if blood sugar is low, somogyi effect
- if blood sugar is normal, dawn
what is gastroparesis and how is it related with diabetes
- delayed gastric emptying in the absence of mechanical obstruction
- affects 30-50% of patients with diabetes
- increases risk of hypoglycemia
what is the biggest thing we are trying to optimize with diabetes management
optimize glycemic control
what are the A1C targets for most adults
7% or less
what are the A1C goals for individuals with type 2 diabetes (and no risk of hypoglycemia)
<6.5%
what are the A1C targets for those who have recurrent severe hypoglycemia, limited life expectancy, or frail elderly?
7.1-8.5%
what is the range preprandial (fasting) for most individuals?
4-7mmol/L
what is the range postprandial for most individuals?
5-10mmol/L
when and what medication to give individual with type 1 diabetes?
insulin right away
what intervention when patient has A1C 1.5% above the target
start with lifestyle changes (nutrition therapy, weight management, and physical activity)
what intervention when patient has A1C over 1.5% of target?
start metformin
- if patient is diagnosed with symptomatic hyperglycemic and diabetes ketoacidosis - treat with metformin and insulin
what are some nutritional recommendations for individuals with diabetes?
- meals do not have to be drastically different than what we usually have
- combining dietary modification + increased physical activity
- T2DM: regular timing and spacing of meals
- CHO - low glycemic index foods
- 30-50g of dietary fiber (10-20g soluble fiber)
- snacking: include protein to slow digestion
nutritional recommendations for individuals with diabetes consuming alcohol
- risk of hypoglycemia because gluconeogenesis is inhibited
- always consume with food
- avoid sweet alcohol, try sugar free
how many g of carbs should individuals with diabetes aim to have at each meal? snack?
meal: 30-60g
snack: 15g
after a meal, blood glucose levels should not rise more than ____ mmol/L
3.0
how to calculate “carb counting”
- grams of CHO minus g of fiber
