Diabetes Flashcards
(20 cards)
What is diabetes
A metabolic disorder characterized by the presence of hyperglycemia due to:
- defective insulin secretion and/or
- Defective insulin action
what are the longterm complication of diabetes
- kidney, eye, nerves, heart, and blood vessels
what % of the population has diabetes
how many people will have it in 2019?
what % is undiagnosed
Prevalence is ~6.3% of the population (all ages and males/females grouped together).
This is expected to be 3.7 million by 2019.
Estimated that up to 20% of diabetes cases are undiagnosed.
Type 1 is also increasing but why is type 2 more?
due to:
- Population is again
- Obesity rate are rising
- Sedentary lifestyle
- Aboriginal people are 3-5x more likely to develop type 2 diabtes
- 77% of new Canadians come from pepulations at increased risk for type 2 diabetes. Eg. Hispanics, asina, south Asian, African descent.
what is type 1
primarily a result of pancreatic beta cell destruction and is prone to ketoacidosis.
what is type 2
may range from predominant insulin resistance with relative insulin deficiency to a predominant secretory defect with insulin resistance.
What is GESTATIONAL DIABETES MELLITUS (GDM)
) refers to glucose intolerance with onset or first recognition during pregnancy.
there are other uncommon forms of diabetes- what do they consist of
specific genetically defined forms of diabetes – NOT common (eg. Single gene defect)
diabetes can also stem from other diseases:
Pancreatitis
Pancreatic cancer and surgical removal of pancrease
Cystic fibrosis
Excess glucocorticoids
- chronic administration as a drug eg. Prednisone
- excess endogenous production (cushing’s syndrome- overactivity of adrenal cortex)
Type 1:
what % of all diabetes
who does it affect
~5-10% of cases of diabetes
Usually but not always < 30 years of age
Occurs more commonly in people of European descent. Marked geographic variation in annual incidence.
Insulin deficient (production).
what are other characteristics of type 1: how much is it increasing per year
how does it appear
Prone to development of ketosis.(excess production of ketones- can progress to ketoacidosis- (low blood ph due to excessive ketones)
Typical Type 1 patient is a child or adolescent at onset
Disease appears more suddenly with severe symptoms.
Less common in pre-school age children but incidence is ing.
Incidence overall is ing at a rate of 3%/year
- Dupports the role of environment etiology.
What causes type 1: etiology
idiopathic (unknown)
Genetic defects plus environmental factors necessary.(they interact) (polygenic)
Genetic pattern transmits (many genes involved) transmit predisposition to diabetes.
# of susceptibility genes under study.|(already have the susceptibility but what triggers it) e.g. candidate =
Environmental factors that have been studied: eg. Vitamin D
viruses – e.g. enteroviruses, rotavirus, rubella but evidence is mostly against
dietary factors. e.g. exposure to cows’ milk protein
vitamin D intake
what is TEDDY
The Environmental Determinants of Diabetes in the Young
large international study to follow high risk infants from birth to adolescence to try to establish the importance of specific environmental factors.
Pathogenesis of type 1
Autoimmune destruction of insulin-producing beta cells in the pancreas by CD4+ and CD8+ T cells and macrophages infiltrating the islets.
When fully developed little or no insulin is produced
what is the treatment for type 1
diet insulin and exercise
Type 2: who does it affect, who prevalent compared all diabetes clinical symptoms what happenes
Usually middle aged or elderly at onset
….But recent alarming incidence in childhood
- Predominimantly adolecents
- Especially in aboriginal population
Most are not ketosis prone (a small proportion are). (but a small proportion is)
Clinical symptoms often subtle and unnoticed by the patient
Accounts for majority of DM (~ 90% )
Patient has a combination of:
- Insulin resistance: diminished tissue response to insulin ( impaired insulin signaling arising from postreceptor defects) AND
- An insulin secretion defect (metabolic defect) (different than type 1)- the dgree of these two in people varies-
Relative importance of insulin resistance versus secretion defect varies among patients
Thus, a heterogenous group of disorders with the common endpoint of hyperglycemia.
Etiology and pathogenesis
Etiology and Pathogenesis
Genetic predisposition (polygenic) PLUS environmental factors.(interacting)
Recall basic endocrine physiology.
How does an endocrine hormone such as insulin exert its action? – it’s a protein- it needs to bind to a receptor on the surface of the cell.
How is it determined which are the target tissues or cells? – the cells with the insulin receptors.
normal glucose tolerance
ability to remove a specified glucose load from the blood and within a defined period of time. Means that their body put out insulin to keep their glucose normal
what is Fasting hyperglycemia
caused by abnormally high hepatic glucose output due to hepatic resistance to insulin action.
what are the pathways in the liver
gluconeogenesis and glycogenolysis
