Treatment of Diabetes Mellitus Flashcards
What are the 4 main components to the treatment of a patient with diabetes mellitus
patient education
glycaemic control
screening for and treatment of complications
screening for and treatment of cardiovascular risk factors
What should all newly diagnosed type 2 diabetic patients receive
verbal and written information about their diagnosis possible complications need for regular follow-up treatment options lifestyle adjustments
Additionally, information on group classes, meetings with a diabetic specialist nurse, dietician, other educational resources such as books, charities and websites
What are important components of non-pharmacological therapy in patients with T1DM
diet and exercise
How is glutted haemoglobin (HbA1c) formed
in a non enzymatic pathway by irreversible attachment of glucose to haemoglobin
What does HbA1c correlate with
mean good glucose over the previous 8-12 weeks
When might HvA1c values be falsely high
when RBC turnover is low
What is the foal of glycemic control
TO achieve normal or near normal glycaemia with an HbA1c of 53mmol/mol
How often is HbA1c measured
every 6 months in those meeting glycemic goals and every 3 months in those who are not meeting glycemic goals and in those whose treatment has changed
Why are cow and pig insulin preparations no longer used
They may cause allergic reactions in some patients
What type of insulin is now used
Synthetic human insulin
What is a short acting form of insulin
soluble (regular) insulin
When is soluble insulin injected
30 minutes before meals
Hypoglycaemia occurs more often in rapid acting insulin or soluble acting insulin
Soluble acting insulin
What are the benefits of using rapid acting insulin analogues
They have faster absorption and more rapid onset and shorter duration of action
What does intensive therapy of insulin regimes involve
administration of a basal level of insulin and primal boluses of a rapid acting insulin preparation
What is an intermediate acting insulin
isophane insulin
What is a long acting insulin analogue
glargine or detemir
What is the difference between long acting and intermediate acting insulin
Long acting do not have a peak effect where as isophane has a 6-10 hour peak effect
They are the basal insulins
What are the rapid acting insulin preparations
lispro
aspart
glulisine
What does the administration of a basal on acting insulin and boluses of rapid acting insulin with meals intend to do
mimic the normal insulin secretion profile of the pancreas
What does the basal insulin suppress
lipolysis and hepatic glucose production
What do the boluses of insulin do
They minimise the postprandial rise in blood glucose
Why is the use of premixed insulins not recommended for patients with type 1 diabetes
intensive therapy in patients requires frequent adjustments of the primal boils of the rapid acting insulin
What is the main benefit of using glargine over isophane insulin
fewer hypoglycaemic episodes with isophane
Why must insulin deter be given twice daily
it has a shorter duration of action than glargine
How is insulin administered
Subcutaneously using single-use syringes with needles, insulin pens with needles or an insulin pump
What are the disadvantages of insulin pumps
they are costly and cumbersome for some patients
Ketoacidosis may occur if the pump malfunctions
How is the needle inserted for administration of insulin
perpendicular to the pinched skin
Held in place for several seconds after insulin injection to avoid insulin leakage after withdrawal of the needle
What determines the length of the needle used
The patient’s weight
Where are potential sites of insulin injection
upper arms
abdominal wall
upper legs
buttocks
Why are the long actin insulins best injected into the leg or buttock
the absorption is slowest here
Why is the rapid acting insulin preparations best injected into the abdominal wall
insulin is absorbed more rapidly here
Why must injection sites be rotated
to avoid the risk of lipohypertrophy
What does insulin requirement depend on
body weight
age
pubertal stage
How much insulin is required for newly diagnosed children
daily insulin dose of 0.5-1U/kg
Patients in ketoacidosis require higher or lower doses of insulin
higher
How much of the total daily dose of insulin does the basal insulin dose comprise of
50%
What are the boluses adjusted according to
the carbohydrate content of the meals and the current blood glucose level
What are the main side-effects of intensive insulin therapy
hypoglycaemia and weight gain
How many times must patients monitor their blood glucose
4-7 times daily (before meals, mid morning, mid afternoon and before bedtime)
What is the purpose of intensive therapy to achieve lower levels of glycaemia in patients with type 2 diabetes
Lowered the risk of microvascular complications
Why should patients with proliferative retinopathy avoid weightlifting
due tot he increased risk of intraocular haemorrhage
Why should patients with neuropathy avoid long distance running or prolonged downhill skiing
Activities may precipitate stress fractures and pressure ulcers in the feet
What drug should be started at the time of diagnosis in patients with T2 DM
Metformin
How does metformin work
it decreases hepatic glucose output, inhibits lipolysis and increases insulin mediated glucose utilisation in the peripheral tissues
It lowers serum lipid and blood glucose by working through LKB1 which phosphorylate sand activates the enzyme adenosine monophosphate activated protein kinase
What are some side effects of metformin
nausea anorexia abdominal discomfort diarrhoea metallic taste in the mouth
What is a rare but serious side effect of metformin
Lactic acidosis
When should a sulphonylurea be started
If lifestyle modification and metformin do not achieve or sustain the glycemic goals within 2-3 months
Who are sulphonylureas indicated in
patients who are not a candidate for metformin or who cannot tolerate it
patients in whom metformin therapy alone is not controlling the glycaemia
How do sulphonylureas work
they bind to an inhibit the ATP dependent potassium channel in the pancreatic beta cells, resulting in a depolarisation of the beta cell membrane, calcium influx and a stimulation of insulin secretion
What is the most common side effect of sulphonylureas
hypoglycaemia
When is hypoglycaemia most likely to arise
after exercise missed meal high drug dose malnourishment alcohol abuse impaired renal or cardiac function FI disease concurrent treatment with salicylate etc.
What are less common side effects of sulphonylureas
nausea
skin reactions (including photosensitivity)
abnormal LFTs
Name some sulphonylureas
glipizide
gliclazide
What is the main thiazolidinediones used for treatment of T2DM
Pioglitazone
When is pioglitazone considered
when sulphonylureas are contraindicated or when hypoglycaemia is particularly undesirable
How do thiazolidinediones work
Act mainly by increasing insulin sensitivity and the peripheral uptake and utilisation of glucose in muscle and fat
They bind to and activate peroxisome proliferator-activated receptors which regulate gene expression
What are some side effects of thiazolidinediones
Weight gain
fluid retention and increased risk of heart failure
What are meglitinedes
short acting drugs that act by regulating ATP dependent potassium channels in pancreatic beta cells thereby increasing insulin secretion
When should a dose of meglitindes be missed
if a meal is missed
What is the most common adverse effect of meglitinicdes
hypoglycaemia
What does GLP-1 do
stimulates glucose-dependent insulin release, inhibits glucagon release
slows gastric emptying
reduces food intake
What is an advantage of Eventide (GLP analogue)
weight loss
What type of drug is sitagliptin
GLP-1 analogue
How are GLP-1 analogues administered
Subcutaneous injection at least twice daily in T2 or with every meal in T1
How does pramlintide work ?
it slows gastric emptying, reduces post-prandial rises in blood glucose and improves HbA1c in both type 1 and 2
What patients may benefit from pramlintide
Type 1 or Type 2 who are inadequately controlled with insulin therapy alone, particularly in those who gain weight despite lifestyle intervention
Why do HbA1c levels rise over time in T2DM
Worsening beta cell dysfunction, decreased insulin release and more severe insulin resistance
What do premixed insulins contain
A mixture of short acting and intermediate acting insulin
What does the effect of exercise on blood glucose depend on
whether the patients is hypoinsulinaemic or hyperinsulinaemic at the time of exercise
Why might exercise cause hypoglycaemia in diabetic patients with adequate serum insulin
Exogenous insulin cannot be shut off and maintains muscle glucose uptake and inhibits hepatic glucose output
What information should patients who exercise be told
May need to reduce the insulin dose that affects the time of day you exercise and the injection should be given 60-90 mins prior
Don’t inject near the muscles that are exercising to prevent increased insulin absorption
How can late hypoglycaemia be avoided
Eating slowly absorbed carbohydrates immediately after exercise (dried fruit)
What can slow the progression of retinopathy
laser photocoagulation therapy
What can slow the progression of nephropathy
administration of an ACE inhibitor or ARB
What is the earliest clinical finding in diabetic nephropathy
Microalbuminuria
Urinary albumin excretion rate of between 30 and 300 mg per day
How is microalbuminuria diagnosed
by measuring the albumin-to-creatinine ratio in a spot urine sample
How do Ace inhibitors work in nephropathy
they both lower iurinary protein excretion and slow the rate of disease progression
What would a diabetic foot exam consist of
Inspection: integrity of skin between toes and under metatarsal heads, erythema, warmth and callus
Check for neuropathy with monofilament and vibration
Peripheral arterial disease: palpation of the pedal pulses and ask history of claudication
What should be obtained if peripheral arterial disease is suspected
Ankle-brachial pressure index
What are some risk factors of microvascular disease
hypertension
obesity
dyslipidaemia
smoking
what would cardiovascular risk factor modification in patients with diabetes include
blood pressure control
screening for and treatment of dyslipidaemia
smoking cessation
aspirin
Why might hypertension develop in diabetics
Reabsorption of the excess filtered glucose along with sodium i the proximal tubules
hyperinsulinaemia
increased arterial stiffness and diabetic nephropathy
What is the recommended BP goal for most diabetic patients
less than 130/80mmHg
What is the main indication for pancreatic islet cell transplantation
problematic hypoglycaemia unawareness
