Diabetes Flashcards
Are outcomes for diabetes improving?
Yes, they have never been better
What is the official definition of diabetes mellitus?
A metabolic disorder characterized by the presence of hyperglycemia due to defective insulin secretion, insulin action, or both
What is the prevalence of Diabetes?
4 million diagnosed (10% of population), but about 30% have diagnosed, undiagnosed, or prediabetes
How has the prevalence of diabetes among adults in Canada shifted over the last 50 years?
It has almost doubled from 14% in 1970 to 29% in 2021
What are some of the reasons for the shift in the number of Canadian adults with diabetes?
Demographic changes (Canadians are getting older, and more people from risk populations are becoming Canadians)
What are the costs associated with diabetes?
Estimated economic impact: $30 billion/yr
Medical costs are 2-3x higher in those with diabetes
What are some complications associated with diabetes?
CVD (the main cause of death), kidney dysfunction, blindness, neuropathy, amputation)
80% will die from heart disease and stroke
How much can diabetes reduce life expectancy?
an estimated 5-15 years
What is the role of the pancreas in blood sugar maintenance?
Euglycemia (ideal blood sugar) is maintained by the following three hormones
Alpha (produce glucagon, account for 30% of islet cells)
Beta (produce insulin, account for 60% of islet cells)
Delta (produce somatostatin, account for 10% of islet cells)
View slides 13-14 to review the interplay of insulin and glucagon
What is the effect of insulin on skeletal muscle?
Muscle is the major site of glucose uptake, and insulin stimulates glucose uptake
Glucose is stored as glycogen in muscle and it is used in energy metabolism (glycogenesis)
Insulin also stimulates the production of proteins from amino acids.
Between meals, energy stored in proteins is harvested by breaking them down back into amino acids. These amino acids can undergo gluconeogenesis, producing glucose
What happens in diabetes with respect to skeletal muscle?
Glucose is never able to be taken up by skeletal muscle cells, therefore limiting energy sources
What is the effect of insulin on the liver?
The liver produces glycogen (product of insulin-induced uptake of glucose), and insulin release following a meal will stimulate the liver to pull glucose from the blood and form glycogen
Insulin also suppresses gluconeogenesis
If the amount of glucose entering the liver is more than the storage capacity for glycogen, insulin promotes its conversion to fatty acids
Between meals, glucagon is released. This hormone promotes glycogenesis and gluconeogenesis, producing glucose
What is the effect of insulin on adipose tissue?
Insulin is effectively a fat storing hormone
Excess carbs are converted into fatty acids and stored as triglycerides in adipose tissue
In starvation or insulin deficiency, fats break down and form ketones. These ketones can be used as an energy source (lipolysis)
What is the effect of insulin on the brain?
The brain gets all of its energy from glucose, but does not depend on insulin for glucose uptake.
The brain is not directly effected by insulin, but low blood sugar due to insulin activity can cause states of confusion to unconsciousness
What are the different classifications of diabetes covered in this course?
Prediabetes:
Impaired glucose tolerance (IGT)
Impaired fasting glucose (IFG)
Diabetes:
Type 1
Type 2
Gestational Diabetes
Describe Type 1 Diabetes Mellitus (T1DM)
Characterized by an absolute lack of insulin secretion
Primarily due to autoimmune beta-cell destruction
Typically, markers of immune destruction are present: islet cell antibodies and insulin antibodies.
Not uncommon to see patients with T1DM to also have other autoimmune diseases
Is Type 1 Diabetes (T1DM) a disease often seen in children?
Yes, it is most commonly has its incidence in patients under 25 (13-14 yo. peak)
But we can occasionally see cases that emerge in the sixth and seventh decade of life
In children with diabetes, most of them have Type 2 diabetes. True or False?
False, most children (95%) have Type 1 diabetes
Adults with diabetes on the other hand show Type 2 diabetes (90%) of the time
Are Type 1 Diabetes (T1DM) incidence rates falling now?
No, it appears that they have a doubling time of a few decades
What initiates Type 1 diabetes and the subsequent breakdown of beta cells?
This immunologic trigger remains elusive, perhaps due to exposure to a virus or toxin
Review slide 24 to closely see how Type 1 diabetes (T1DM) progresses in terms of beta cell function
When do symptoms in Type 1 Diabetes manifest?
After 80-90% of beta cells have been destroyed
What is the “honeymoon phase” in Type 1 Diabetes (T1DM)?
Following initial correction of hyperglycemia with exogenous insulin, causes endogenous insulin production to recover temporarily
This usually occurs in the days to weeks following starting insulin
This “recovery” is temporary, so insulin therapy and monitoring continues