Diabetes and its treatment Flashcards
how is insulin made
beta cells of pancreas –> proinsulin –> breaks down in to C peptide and insulin
effects of insulin
decreases blood glucose
increases glucose in liver, kidneys, muscle
normal range of blood glucose levels
4-7M/m
define diabetes
metabolic disorder characterised by chronic hyperglycaemia resulting from defects in insulin secretion/ action/ both
difference between type 1 and type 2 insulin
type 1: insulin deficiency. autoimmune destruction of pancreas
type 2: insulin resistance (due to other hormones/ obesity)
why is obesity linked to insulin type 2 diabetes 2
hormones linked to obesity prevent insulin binding to receptor IRS1
mutations of 2nd messengers
what is cut off point for having diabetes
4-7m/M normal
8-10 impaired glucose tolerance
11 M/m DIABETES
IGT stand for and relevance to diabetes
impaired glucose tolerance
50% go on to develop diabetes
how doe HbA1c test for diabetes work
looks at glucose over ast 2-3 months (lifetime of current haemoglobin
HbA1c cannot pick up rapid changes, so do not use…
cannot pick up rapid changes, so do not use:
- children/ young people
- symptoms suggesting type 1 diabetes
- short duration diabetes symptoms
- pts at high risk of diabetes who are acutely ill
- pts taking medication that may cause rapid glucose rise eg corticosteroids
when HbA1c can be innacurate
TABLE ON DIAGNOSIS VALUES
- HIGH HbA1c 2: persistant HbF (thalassaemia), uraemia (carbamylates Hb) *high HbF Fucking High)
- LOW HbA1c 2: haemolysis, inc red cell turnover, blood loss (HbS, HbC, Low and SexC)
3 types of diabetes
1,2, gestational
2 types of pre diabetes
impaired fasting glycaemia
impaired glucose tolerance
impaired fasting glycaemia:
a. cause
b. risk of diabetes
c. risk of disease
d. treatment
e. preventing progress to diabetes
a. cause: unknown, ?glucose sensitising
b. risk of diabetes: 50%, 50% recovery to normal
c. risk of disease: not known
d. treatment: healthy diet, yearly glucose checks
e. preventing progress to diabetes: not known
impaired glucose tolerance:
a. cause
b. risk of diabetes
c. risk of disease
d. treatment
e. preventing progress to diabetes
a. cause: insulin resistance
b. risk of diabetes: 50%, 50% return to normal
c. risk of disease: heart disease, cerebrovascular disease
d. treatment: diabetic diet, yrly glucose checks, tx of cardiac risk factors
e. preventing progress to diabetes: exercise, weight loss
causes other than diabetes for
a. insulin deficiency
b. insulin resistance
a. insulin deficiency: cancer/ alcohol –> destroy pancreas
b. insulin resistance: receptor abnormalities (leprechaunism, insulin resistance symptoms A and B)
excessive hormones (cushing’s, acromegaly)
type 1 diabetes:
a. incidence
b. cause
c. pathology
a. incidence: 1/10 000, M>F, normally
6 symptoms of type 1 diabetes
- polyuria (bedwetting)
- thirst esp for sugary drinks
- weight loss
- dehydration
- ketoacidosis
- coma
possible genes for type 1 diabetes
DR3, DR4
new options for type 1 diabetes tx
- insulin pumps (continuous insulin –> less hypos but v expensive)
- inhaled insulin (only 1/10 dose absorbed. long term safety not known)
- islet cell transplant (beta cells)
- pancreas transplant
type 2 diabetes
a. incidence
b. cause
c. pathology
a. incidence: 1/1000 (more undiagnosed), m=f, normally >40
b. cause: genetic > environment
c. pathology: insulin resistance, insulin deficiency
relationship between birthweight and type 2 diabetes
low birthweight, go on to be heavy adults –> higher risk of diabetes
4 things which contribute to type 2 diabetes development
birthweight
genetics
exercise
fat distribution (upper body obesity ie in abdomen mroe risk of diabetes)
2 step model of type 2 diabetes
genetic predispositon –>
insulin resistance –>
relative lack of insulin –>
hyperglycaemia
diet/ activity levels/ level of obesity all contribute to this process
3 types of presentation of type 2 diabetes
- non-symptomatic: routine screening urine/ RPG
- metabolic: thirst, polyuria (less acute than type 1)
- non-metabolic 8: blurred vision, intertrigo, peripheral neuropathy, angina/MI, UTI, pruitis vulvae/ balanitis, peripheral vascular disease, foot ulcers
type 2 diabetes tx for
a. thin people
b. fat people
a. thin people: diet, exerise -> sulphonylureas -> +metformin -> +newer drugs -> insulin
b. fat people: diet, exercise, weight loss -> metformin -> +sulphonylureas -> +newer drug -> insulin
what is the incretin effect
twice as much insulin released when glucose taken orally compared to IV due to GLP1 (glucagon like receptor 1)
5 effects of GLP1 and what does it stand for
glucagon-like-receptor 1
pancreas (2):– enhances glucose-dependent insulin secretion in beta cells of pancreas
–alpha cell suppression of postprandial glucagon secretion
-reduces hepatic glucose production
-slows rate of gastric emptying
-promotes satiety, reduces appetite
what causes GLP-1 secretion
ingestion of food
what is HbA1c and its relationship with diabetes
glycated haemoglobin
indicates blood glucose level –> high HbA1c, high risk of diabetes
mechanism of dapagliflozin
TABLE ON DIABETES DRUGS
Blocks SGLT2 in proximal tubule of kidney –> less reabsorption
list
a. insulin sensitisers
b. insulin releasers
c. insulin replacement
a. insulin sensitisers: thiaolidinediones, metformin
b. insulin releasers: sulphonylureas, meglitinides
c. insulin replacement: insulin
treatment of gestational diabetes
85% diet
15% diet + insulin
4 factors increasing risk of gestational diabetes
obese
previous diabetes in pregnancy
asian
age >35
when in pregnancy does gestational diabetes often occur
2nd/3rd trimester
future prospect of gestational diabetes
50% get diabetes in next 5 yrs
15% get diabetes in next pregnancy
complications of gestational diabetes 3
- large baby
- stillbirth
- death of mother
acute complications of diabetes 2
hypoglycaemia
diabetic comas
chronic complications of diabetes 6
microvascular 3: neuropathy, retinopathy, nephropathy
macrovascular 3: IHD, CVA, PVD
symptoms of hypoglycaemia:
a. early warning
b. mild
c. more advanced
d. unconsious
a. early warning: shaking, trembling, sweating, pins&needles, hunger, headache, palpation
b. mild: double vision, slurred speech, difficulty concentrating
c. more advanced: confusion, change of behaviour
d. unconscious: epileptic fits, weakness
draw diagram of normal hormonal responses to hypoglycaemia
list whats missing in diabetes
see lecture
diabetes:
- no adrenaline to increase hepatic glucose production
- no glucagon to increase hepatic glucose production
3 causes of hypoglycaemia
- missed meal
- too much insulin
- alcohol
treatment of hypoglycaemia if the pt is:
a. conscious
b. drowsy
c. unconscious
a. conscious: oral glucose
b. drowsy: hypostop
c. unconscious: s/c glucagon, IV 50% dextrose
2 types of diabetic comas
- diabetic ketoacidosis (DKA) with type 1 diabetes
- hyperosmolar non-ketoic hyperglycaemia (HONK)
risk of these with each type of diabetes
a. retinopathy
b. neuropathy
c. nephropathy
a. retinopathy: 100% type 1 pts
b. neuropathy: increase with time. 70-100%
c. nephropathy: 30-40% type 1, less in type 2 pts
are micro/ macrovascular complications present in impaired glucose tolerance (IGT)
macrovascular
what reduces risk of macrovascular complications
metformin
what is made in the following pancreatic cells
A cells
B cells
D cells
A cells: glucagon (A away, glucose away)
B cells: insulin
D cells: somatostatin
