Type 2 Diabetes Flashcards
glucose sources
intestinal absorption, glycogenolysis, gluconeogenesis
In fasting state, glucagon levels increase/decrease
increase
Glucagon
stimulates glycogenolysis and gluconeogenesis
In fasting state, insulin levels increase/decrease
decrease
During eating, insulin levels increase/decrease
increase
Which tissues absorb glucose due to insulin?
muscle, liver, adipose
Insulin resistance
reduced response to circulating insulin
Insulin resistance hyperglycemia
liver, muscle, adipose glucose intake is low and liver glucose output is high –> hyperglycemia
There is a _______ relationship between insulin secretion and insulin resistance
hyperbolic
As one gains weight and becomes obese, it is possible to maintain glucose balance if ____
pancreas increases insulin output –> this ability drops off over time
Prediabetes
impaired glucose tolerance, impaired fasting glucose
Why do post-prandial sugars rise first after some years of prediabetes?
as ability to ensure high level of insulin secretion tapers off and starts declining, the body has a more difficult time coping with high carbohydrate load vs. simply shutting off liver glucose production –> post prandial sugars rise before fasting glucose
First indicator of diabetes
rise in insulin
By the time of diagnosis, ____% of beta cells are long gone.
50%
normal fasting glucose
100 = more cardiovascular risk)
2hr plasma glucose after 75gm CHO load
<140 mg/dL
100<200 mg/dL
prediabetes
T/F most people with prediabetes develop type 2 diabetes within 10 years
T
First phase of insulin secretion
task is to take care of just-consumed CHO and shut down glucose production –> insulin in beta cell granules
Second phase of insulin secretion
task is to maintain blood sugar that has been absorbed prior –> gradual increase in insulin
___ phase of insulin secretion is missing in T2D.
first phase
Deposition of ____ disrupts alpha/beta cell communication.
amyloid –> inappropriately high glucagon secretion stimulates liver production of glucose and therefore hyperglycemia
intestinal hormones that are released in response to food ingestion
incretins
Incretins
glucagon like peptide 1 (GLP1) and gastric inhibitory polypeptide (GIP) stimulate insulin secretion in the presence of glucose –> account for 60-70% of postprandial insulin response
Incretin response
difference between insulin load from oral glucose and from iv glucose
T/F response to GLP1 is preserved in diabetes
T
GLP1 effect on glucagon
reduces glucagon –>reduces hepatic glucose output
GLP1 effect on stomach
slows gastric emptying –> attenuates post-prandial hyperglycemia
GLP1 effect on CNS
promotes satiety and reduction of appetite
4 main defects in Type 2 Diabetes
decreased insulin action, decreased insulin secretion, inadequate glucagon suppression and excess hepatic glucose production, defective incretin response
Risk factors for T2D
obesity, race, metabolic factors, lifestyle, genetics, gestational diabetes, intrauterine
Nonspecific clinical presentation of T2D
fatigue, blurry vision, poor wound healing, dry mouth/skin, recurrent infections (candadiasis)
Classic symptoms of T2D
polyuria/dipsia/phagia, unexplained weightloss
Physical exam findings of T2D
obesity, skin changes, candidal infection, fundoscopic/neurologic (decreased sensation)/feet changes (ulcers)
skin changes in T2D
acanthosis nigricans, skin tags, furuncles and carbuncles
Diagnostic criteria for T2D
fasting glucose>126 on two separate occasions or random glucose>200 with classic sx or 2hr glucose test >200 or hba1c>6.5%
_____ reflects average plasma glucose level over past 2-3 months
hemoglobin a1c
After gastric bypass levels of _____ are highg
GLP1
