Trigger 1: Diabetes Flashcards
diabetes mellitus
hyperglycaemia due to insufficient insulin secretion
Clinical def:
fasting blood glucose over 7mmol/L
type 1 incidence vs T2
10% vs 90%
Consequences of diabtes
- Reduces life expectancy between:
o 5 to 14 years in people with T1
o 6 years for Y2 - Contributes to kidney failure and CVD
Monogenic forms
Single gene defects causes diabetes (due to B-cell defect)
types of monogenic diabetes
- Neonatal
- Maturity onset diabetes of the young
Neonatal gene defects
- Most common mutations in KCNJ11 and ABCC8 (form subunits of kATP channel)
(2) Maturity onset diabetes of the young (MODY) gene defect
- 6 genes have been identified that account for 87% of UK MODY:
i. HNF1A
ii. HNF1B
iii. Hnf4A
iv. Glucokinase
Type 2 diabetes
Hyperglycaemia due to insufficient secretion. Combination of increased insulin resistance and beta-cell defects. Can have very high levels of insulin secretion, but due to insulin resistance glucose levels remain high.
presentation of T2DM
Presentation of type 2 diabetes Long duration Older at diagnosis: 50s and 60s Overweight Strong family history Thirst, hunger, polyuria Oral and vaginal thrush Tiredness, sleepiness , change of behaviour
Treatment of type 2 diabetes
Diet Exercise Drugs to improve insulin sensitivity Drugs to stimulate insulin secretion Drugs to promote glucose excretion via the kidneys Insulin injections
Drugs to stimulate insulin secretion
- GLP-1 agonists
- Sulphonylureas
Drugs to promote glucose excretion via the kidneys
- Gliflozins
Drugs to improve insulin sensitivity
- Metformin
- Pioglitazone
Type 1 diabetes
Autoimmune destruction of insulin-producing beta cells of the pancreas. Due to a presence of autoantibodies and autoreactive T-cells directed against islet cells or their antigenic constituents e.g. Insulin, GAD65, IA-2.
People with type 1 diabetes selectively lose the insulin-secreting B-cells from their islets
Possible reasons for destruction of B cells in T1DM
- Vit D def
- Virus?
- environmental toxins
- hygiene hypothesis
- overt diabtes
precipitating events
Cause (an event or situation, typically one that is undesirable) to happen suddenly, unexpectedly, or prematurely- in T1D occurs in older people
Symptoms of T1DM
- thirst
- thinner
- tired
- toilet
Characteristics of T1DM
- Young age onset
- Sudden onset
- Thin
- Immune-auto antibodies, T cells
- Genetic- MHC class II and I, CTLA4
- Family history
- Insulin deficient
- Ketoacidosis
treatment of T1DM
- Insulin replacement therapy- injections or pump
- Regular blood glucose monitoring
- Carbohydrate counting/exercise
- Transplantation- islet or pancreas
Testing for diabtes
- HbA1c
- FPG
- OGTT
- Random venous blood glucose
HbA1c
Measures % of glycated H in the blood
Increased in more hyperglycaemic periods
>6.5% for clinical diagnosis
Advantage: doesn’t require fasting and representative of glycaemic control form the past 3 months
Fasting blood glucose
> 7mmol/L
Random venous blood glucose
> 11.1mmol/l
