Type 2 Diabetes (Patho) Flashcards
(slides 25-54)
T2DM accounts for how many of all diabetes cases?
90-95%
T2D is a progressive metabolic disease characterized by what?
insulin resistance & beta cell exhaustion in the pancreas
What percentage of T2DM cases are r/t obesity?
80%
If both parents have Type 2 DM, then there is a __% chance, the child will be too
40%
List the pathological mechanisms behind T2DM (4)
- Insulin resistance
- Deranged secretion of insulin
- Increased glucose production
- Beta cells become exhausted… apoptosis
List the risk factors for T2DM (12)
- Family history
- Obesity
- Ethnicity
- Age
- Gestational diabete
- Delivery of babies > 9 lbs
- Hypertension
- Metabolic Syndrome
- Polycystic ovary Syndrome (PCOS)
- Smoking
- Alcohol
- Corticosteroid use
How does insulin resistance lead to beta cell exhaustion?
beta cells try to compensate for it by producing more insulin. However, they eventually become exhausted and stop functioning properly, worsening the condition.
What is significant about ethnicity as a risk factor for T2DM?
African Americans, Hispanics, and Native Americans are at higher risk for diabetes than Asians or Caucasians. However, all ethnic groups are at risk.
Women with PCOS are at higher risk for T2DM due to what?
insulin resistance
How does smoking increase the risk for T2DM?
it increases inflammation and causes vasoconstriction, both of which contribute to higher diabetes risk, and worsening insulin resistance
Alcohol can have have negative effects on ______ and ______ regulation
insulin and glucose regulation
Explain the process of what occurs in a patient with T2DM whose blood sugar is high
- Initially there is increased insulin secretion by the Beta cells to bring down the blood sugar
2. Insulin is not effective and ultimately can not bring it down
3. Because the insulin levels are high…the body increases the level of glucose
4. Beta cells become exhausted
By the time many type 2 diabetics are diagnosed, they have lost about 50% of what?
beta cell function
List the features of metabolic syndrome (5)
- increased waist circumference or belly fat
- high triglycerides
- elevated BP
- high blood sugar
- a low HDL (good cholesterol)
What is Acanthosis Nigricans? What is it a sign of?
A sign of insulin resistance, where the skin becomes darker and thicker, often seen around the neck or armpits.
Visceral fat is particularly associated with ______ _______.
what is a key indicator of this?
insulin resistance
abdominal obesity is a key indicator
Why does obesity cause insulin resistance?
- Causes increase in adipose and free fatty acids
2. Induces inflammation and release of the associated inflammatory mediators
3. Increases stress on pancreatic B cells as insulin is increased
4. Results in liver increase glucose in the blood (impaired suppression)
elevated blood glucose levels can damage blood vessels, contributing to what?
the development of atherosclerosis, or plaque buildup in the arteries
What are chronic high insulin levels?
Individuals with insulin resistance often have chronically elevated insulin levels.
This can worsen the glucose imbalance and contribute to further vascular damage
What is one of the best ways to improve insulin sensitivity and reduce blood glucose levels?
regular exercise
How does exercise improve insulin resistance and lower blood glucose?
- Increases mitochondrial enzymes
- Increases insulin sensitivity
- Triglycerides get broken into free fatty acids to use for fuel
- Decrease BS, decrease insulin
- Increase glucagon
- Causes uptake of glucose from circulation
What is the difference between insulin sensitivity and insulin resistance?
Insulin sensitivity → how well your cells respond to insulin
insulin resistance → when cells become less responsive to insulin, potentially leading to high blood sugar and related health issues
Why does a sedentary lifestyle increase insulin resistance?
Those who do not exercise have decreased intracellular enzymes such as pyruvic acid
How can one’s diet cause insulin resistance?
A high glycemic diet (rich in processed foods and sugary foods) exacerbates insulin resistance.
Processed foods (rich in preservatives and artificial ingredients) contribute to poor health outcomes, unlike fresh, whole foods commonly consumed in Europe.
How is diabetes diagnosed? (4)
- Fasting blood glucose >126 (2 readings)
OR
- A 2 hour plasma glucose during an Oral Glucose Tolerance Test (OGTT) >200
OR
- Random blood glucose > 200 with hyperglycemic symptoms
OR
- Hgb A1C > 6.5% (2 readings)
What is a Hgb A1C measurement? What does it tell us?
A long-term measure of blood sugar control over 120 days that is used to diagnose or monitor diabetes pts
It reflects the amount of glycated hemoglobin (hemoglobin bound to glucose) in red blood cells, providing insight into long-term blood sugar levels.
What is the ideal Hgb A1c measurement for diabetic management?
below 7%
What is the diagnostic criteria for fasting blood glucose for DM in both pre-diabetes and diabetes?
Prediabetes → 100 to 125 mg/dL
Diabetes → 126 mg/dL or greater
What is the diagnostic criteria for 2hr plasma glucose during OGTT for DM in both pre-diabetes and diabetes?
Prediabetes → 140 to 199 mg/dL
Diabetes → 200 mg/dL or greater
What is the diagnostic criteria for random plasma glucose in diabetes mellitus pts?
200 mg/dL or greater
What is the diagnostic criteria for A1c for DM in both pre-diabetes and diabetes?
Prediabetes → 5.7% to 6.4%
Diabetes → 6.5% or greater
What is the normal A1c value?
< 5.7%
What is the normal fasting plasma glucose value?
</ 99 mg/dL
what is the normal OGTT value?
</ 139 mg/dL
Does glucose normally go into the RBC?
No, but the membrane is very permeable
What happens between glucose & RBC if the glucose level is chronically high?
when chronically high, the glucose will move into the RBC
once glucose is in the RBC, it can not leave
Hypoglycemia is characterized by what blood glucose level?
70 mg/dL
List the common causes of hypoglycemia (7)
- excessive exercise
- alcohol
- poor food intake
- too much insulin
- stress
- surgery
- medications
What occurs in the body when hypoglycemia occurs?
- The hypothalamus & portal vein in the liver sense a decreased glucose. In response sends signals to the adrenal gland, pancreas, and liver
- Epinephrine and Glucagon are released causing activation of the SNS which is responsible for most of the S&S
- As hypoglycemia continues, epinephrine and glucagon promote glycogenolysis and gluconeogenesis in the liver
Blood sugar value for mild hypoglycemia sx?
Blood sugar value for severe hypoglycemia sx?
mild → 100-55
severe → <55
List the mild sx of hypoglycemia (8)
- Fatigue
- Sweating
- Hunger
- Dizziness
- Rapid heart rate
- Anxiety
- Irritability
- Shakiness
List the severe sx of hypoglycemia (7)
- Blurred vision
- Impaired thinking
- Confusion
- Palpitations
- Loss of consciousness
- Seizures
- Coma
How to Tx hypoglycemia in a conscious vs unconscious pt?
Conscious patient → give a quick source of sugar, such as candy, juice, or glucose tablets.
Unconscious patient → give glucose IV D50, or sublingual glucose
What happens in somatic diabetic neuropathy? (2)
Diminished perception → vibration, pain, temperature
Hypersensitivity → light touch; occasionally severe “burning” pain
What happens in autonomic diabetic neuropathy? (4)
Defects in vasomotor and cardiac responses
Urinary retention
Impaired motility of the gastrointestinal tract
Sexual dysfunction
how can diabetic neuropathy increase the risk for infection?
individuals may not feel injuries or wounds that become infected
List the key characteristics of Hyperosmolar Hyperglycemic Syndrome (HHS) (7)
- only seen in type 2 diabetes
- severe hyperglycemia (>600)
- hyperosmolality
- dehydration caused by insulin resistance
- absence of ketones
- cells are not absorbing glucose
- can develop over several days to weeks
Explain the pathophysiology behind HHS (4)
- Blood becomes hyperosmolar, causing intracellular fluid to move out of the cells into the extracellular space.
- Potassium, the major intracellular electrolyte, is also pulled out of the cells into the extracellular fluid. This leads to potassium imbalance
- Cells are not absorbing glucose and “sense” starvation, leading to glycogen breakdown and gluconeogenesis activation.
- This results in a significant rise in blood glucose levels, typically over 500-600 mg/dL or higher.
List the similarities between HHS and DKA
HHS sets up the same hyperosmolarity as in DKA:
- ECF increases and there is intracellular dehydration
List some of the causes of HHS (5)
- infection
- non-compliance with diet 3. non-compliant with medications
- undiagnosed
- substance abuse/alcohol
List the sx of HHS (9)
- extreme glucose level
- rapid/thread pulse
- hypotension
- profound dehydration
- polydipsia
- polyuria
- confusion
- disorientation
- possible seizure
- coma
what is the tx options for HHS? (3)
Hydration (given first)
IV insulin
Electrolyte replacement
What does rehydration do to tx HHS?
Rehydration is the first step in treatment
IV fluids (e.g., normal saline) are given to correct dehydration and restore electrolyte balance.
Rehydration helps move glucose back into the cells and corrects potassium imbalances.
How is insulin used to tx HHS?
Regular insulin is administered after rehydration to lower blood glucose levels.
Insulin helps regulate glucose and prevent further complications, but hydration must come first to stabilize the patient.
What electrolyte levels need to be monitored in HHS and why?
Potassium levels → rehydration and insulin therapy can lead to potassium shifts back into the cells, potentially causing hypokalemia (low potassium).
Magnesium levels → these can drop during rehydration.
