ENDO - Diabetes assessment & Mx Flashcards
What are the types of diabetes?
Definition base on etiologic differences
Type 1: Autoimmune, idiopathic, absolute insulin deficiency 2o beta cell destruction
Type 2: spectrum with insulin resistance and varying degrees of insulin secretion
•In developed countries, 90% overweight ± metabolic syndrome
Other – 5% cases
•Gestational (Pregnancy related)
•Terms like insulin dependent, non insulin dependent, juvenile onset, maturity onset etc. no longer used
How do you diagnose diabetes?
- RBG
- FPG (fasting plasma glucose)
- HbA1C
- 2 hour value in OGTT (oral glucose tolerance test with 75g)
–Symptoms + RBG >11.1mmol/L or
–FPG > 7.0mmol/L* or
–HbA1C > 48 mmol/mol (6.5%)*†
–2 hour value >11.1mmol/l in the OGTT
*In absence of unequivocal hyperglycaemia with acute metabolic decompensation, criteria should be confirmed by repeat testing
† HbA1C became available as a Medicare funded test for the diagnosis of diabetes in November 2014.
What is the FPG (fasting plasma glucose) of normal person?
Less than 6.1mM
What is the FPG (fasting plasma glucose) of an impaired fasting glucose person?
FPG 6.1-6.9mM
What is the FPG (fasting plasma glucose) of a diabetic?
> 7.0mM
Describe (3) characterisations of type 1 diabetes
- Characterised by autoimmune destruction, of the pancreatic beta cells
- Absolute insulin deficiency
- Insulin required to prevent death
Pathophysiology of T1D
- genetic susceptibility
- environmental susceptibility
- prediabetic stage
- when diabetic
- Genetic susceptibility (MZ concordance less than 50%)
- Environmental event triggers process susceptible people
- Prediabetic stage: mulitple antibodies (eg. Anti GAD, anti islet cell) detected in blood. Variable duration
- Diabetes – occurs when insufficient insulin is produced to maintain normal blood glucose (by this stage most beta cells have been destroyed)
What is the (5 steps) natural history of T1D?
- Genetically at risk (genetic predisposition)
- Environmental triggers (insulitis; beta cell damage)
- Islet antibody positive (insulitis; beta cell damage)
- First phase insulin response impaired (pre-diabetes)
- Diabetes
(3) characterisations of T2D
- Most common type of diabetes
- Variable degrees of insulin deficiency and resistance
- Often part of the metabolic syndrome
Pathophysiology of T2D
- genetic susceptibility
- environmental susceptibility
- Both beta cell defects and insulin resistance are present
- Major environmental factor is obesity
- GENETICS (MZ twin concordance up to 80%; higher than T1D)
- Likely polygenic, > 250 candidate genes examined
When you’re doubtful of T1D or T2D as diagnosis, what (2) tests can you do?
- measure C-peptide (good indicator of endogenous insulin production). There will be none in T1D
- Anti GAD & anti islet cell antibodies: likely to be positive in T1D
Above what glucose level consistently would cause tiredness & susceptibility to infection?
> 13-14mM
What (5) factors determine risk for long term complications of T2D?
–Duration of diabetes: in Type 2, complications present in 50% at time of diagnosis because diagnosis is often very late
–Degree of glucose control: HbA1C
–Degree of BP control
–Control of other CV risk factors: Lipids, Smoking
–Individual (genetic) susceptibility
What are the principals of T2D Mx?
- Healthy eating / weight loss if overweight (refer to dietitian. Low GI, reduced fats)
- Exercise
- Oral anti-diabetic agents
- Self blood glucose monitoring for some patients*.
- Regular surveillance for microvascular complications (eyes, kidneys, nerves)
- Risk reduction macrovascular complications (blood pressure, lipids, smoking)
- Useful particularly of patients treated with insulin or sulphonylureas where hypoglycaemia may occur.
Discuss the relationship between BGL & exercise in diabetes
- Increases glucose uptake into muscle
- Can stimulate release of stress hormones leading to short term glucose increase. However this is variable depending on intensity and duration.
- In the longer term, BGL’s usually decrease.
- Hypoglycaemia following exercise can occur up to 24 hours later (if treated with insulin or SU).
- Improved sensitisation of muscle to exercise can last 2-3 days
- Best to exercise consistently and regularly.
