Diabetes Flashcards
How does the patient present?
Polyuria Polydipsia Not sleeping well Wakes up during the night to use the bathroom Drinks more than usual
What question does the GP ask?
How much water is he passing a day?
How much water is he drinking a day?
What is prediabetes?
Blood sugars are higher than usual, but not high enough for you to be diagnosed with Type 2 diabetes.
Means that you are at high risk of developing type 2 diabetes
What are other terms for prediabetes?
Borderline diabetes
Impaired glucose regulation
Non-diabetic hyperglycaemia
What are the risk factors for diabetes?
Over 25 for African-Caribbean, Black African or South Asian
Over 40 if you are white
6x more likely if you have a direct family member
4x more likely in above groups
High blood pressure
Overweight
Large around the middle
How can type 2 diabetes be prevented?
Manage weight
Eat healthy, balanced diet
Be more active
What constitutes a healthy diet?
Mediterranean diet Dietary approaches to stop hypertension (DASH) Vegetarian and vegan diets the Nordic Diet Moderately cutting down on carbohydrates
What is the NHS Diabetes Prevention Programme?
Joint commitment from NHS England, Public Health England and Diabetes UK
Deliver at scan, evidence-based behavioural interventions for individuals identified as being high risk
Why has the programme been implemented?
Many cases of type 2 are preventable
Behavioural interventions can greatly reduce the risk
Treatment accounts for 10% of NHS’s budget
What are the aims of the programme?
Reduce incidence
To reduce incidence of associated complications with diabetes e.g. heart, stroke, kidney and eye problems
Reduce health inequalities associated with diabetes
How was the NHS DPP developed?
Review of the available evidence from existing programmes
Informed development of core components
Established a user involvement group
Demonstrator sites selected
Commissioned analysis of health survey for England data
What is the intervention?
Core goals:
Achieving healthy weight
Achievement of dietary recommendations
Achievement of physical activity recommendations
Who is eligible to go on the programme?
Prediabetics
HbA1c 42-48mmol/mol
Fasting plasma glucose 5.5-6.9mmol/l
What are the referral routes into the programme?
Identified as having an appropriately elevated risk level
NHS Health Check Programme
Identified through opportunistic assessment as part of routine clinical care
What are the core defects in type 2 diabetes mellitus?
Insulin resistance in muscle and the liver
Impaired insulin secretion by pancreatic beta cells
What are other defects in type 2 diabetes mellitus?
Resistance to glucagon-like peptide 1 (GLP1) contributes to failure in function of beta cells
Increased glucagon levels and enhanced hectic sensitivity to glucagon contribute to the excessive glucose production by the liver
Resistance in adipocytes results in accelerated lipolysis and increased plasma free fatty acid levels (also contribute to failure of beta cells)
Increased renal glucose reabsorption maintains hyperglycaemic levels
Resistance to appetite suppressive effects of a number of hormones contributes to weight gain
How does glucose enter cells?
Insulin binds to insulin receptor on cell membrane
Glucose enters via GLUT4 transporter (insulin dependent)
Found in muscle and adipose
Via facilitated diffusion
What happens to glucose after it enters the cell?
Glycolysis
Link reaction (oxidation of pyruvate)
TCA cycle
What are the main features of GLUT-1?
Found in: endothelium and erythrocytes
Function: Basal transport (insulin independent)
What are the main features of GLUT-2?
Found in: Kidney, small intestine, liver and pancreatic beta cells
Where is active transport used to transport glucose?
Kidney and Intestine
What are the main features of GLUT-3?
Found in: Neurones and placenta
What happens when someone is insulin insufficient?
Cells weight GLUT4 transporters will be relatively deplete of glucose
Others with other transporters will intake glucose down conc. gradient
Per molecule of glucose, how many ATP can be produced?
Roughly 30
What actions are prompted by insulin in the liver?
Tells liver to take up and store glucose (glycogenesis) Decreased gluconeogenesis Decreased lipolysis Decreased glycogenolysis Increased lipogenesis
What actions are prompted by insulin in muscles?
Increased glucose uptkae
Increased glycogenesis
Increase protein synthesis
Decreased protein catabolism
What actions are prompted by insulin in fat?
Lipogenesis
Prevent lipolysis
Increased glucose uptake
What occurs in type II diabetes?
Tissues are insulin resistant
Body produces insufficiently producing insulin
What can initially occurs in type II diabetes?
Hyper-production of insulin by beta cells
Eventually they can no longer produce this amount
This is when a patient become diabetic
What would you see in the bloods of a diabetic patient?
Increased free fatty acids
Increased blood glucose
How can being overweight contribute to diabetes?
Visceral fat is particularly resistant to insulin
Diabetes susceptibility genes
Adipokines come from fatty tissue have toxic action on beta cells
Inflammation
In what order would the condition come in?
Normoglycaemia
Impaired fasting glucose
Impaired glucose tolerance
Type 2 diabete mellitus
What is a normal fasting glucose?
<5.5mmol/l
What is a normal post prandial glucose?
<7.8mmol/l
To obtain result you give them a 75g oral glucose load and result taken 2 hours after
What is a normal random glucose?
<11.1mmol/l
What are the main features of impaired fasting glucose?
Abnormal fasting glucose but not diabetic levels
Normal post-prandial and random
What are the main features of impaired glucose tolerance?
Cannot manage glucose adequately after a meal
Post-prandial always abnormal
Fasting glucose <7mmol/l, can be normal
Random always normal
What values define diabetes?
Fasting glucose >7mmol/l
Post-prandial glucose >11.1mmol/l
Random >11.1mmol/l
What else need to be considered before giving a diagnosis?
HbA1c
Do they have symptoms?
What is impaired fasting glucose?
Predominantly hepatic insulin resistance leads to continuous glucose output from the liver
What is impaired glucose tolerance?
Predominantly muscle insulin resistance plus impaired post-prandial insulin release results in poos cellular glucose uptake
Which test is the least useful in diagnosing T2DM?
Urine dip test
Glucose may be present at a level below diabetes
Other conditions can cause glucose to be present in urine
What is the renal urine threshold for glucose?
About 10mmol/l
Varies from person to person
And within a person
What is an HbA1c?
Haemoglobin that has become glycosylated
Occurs non-enzymatically
Advantages of HbA1c as a diagnostic tool?
Hb has a lifespan of 120 days a so show glucose levels over a three month period
Patient doesn’t need to fast
No need to waste resource on sugary drinks
Patient doesn’t need to come in 2 hours beforehand
Disadvantages of HbA2c as a diagnostic tool?
Co-morbidities may affect result e.g. Anaemia, HIV, pregnancy
Relies on normal red blood cell/ Hb levels to compare with reference range
If RBCs die early will give a falsely low reading
What is a behavioural insight?
Uses knowledge of how and why people behave to encourager positive behaviour change
Considers psychology, social anthropology and behavioural economics
How can you optimise uptake to a programme e.g. DPP?
Discussion with GP who can explain admission
Infographic and leaflets with simple instructions
Target high risk group by sending personalised letters
How can you make an infographic most effective?
Think about the audience and adjust content
Language
Pictures featuring people from different ethnicities and sizes
When talking about food think about different cultures
How can you ensure maximum retention on the programme?
Local/ less travel Convenient times Cater with healthy foods Incentives e.g. discount for health food store Make them fun and engaging
How can the DPP help with behavioural changes?
Progress monitoring Social activities with groups of people with similar goals Motivate each other Forums for healthy recipes Prepare for shogun with a list
What is the EAST framework for behavioural change?
Easy
Attractive
Social
Timely
What is the medication used for diabetes?
Metformin
Why is Metformin used as first line treatment of T2DM?
Few serious side effects Safe to take for a long time Well tolerated Oral tablet- easy to take Does not cause weight gain Reduces risk of cardiovascular events Cheap drug
Where does metformin act??
Liver Fat Muscle Wide mechanism of action In cells with GLUT4 it increases translocastion of GLUT4 to membrane
What are the symptoms of T2DM?
Nocturia Polydipsia Fatigue Weight loss Thrush Itching around penis/vagina Cuts and wounds taking longer to heal Blurred vision
What are the two types of complications that can arise from diabetes?
Microcvascular
Macrovascular
Give some examples of microvascular complications?
Retinopathy—> Blindness
Nephropathy—> renal failure
Neuropathy—> Impotence and diabetic foot disorders
Give some examples of macrovascular complications?
Cardiovascular diseases
E.g. heart attacks, strokes, insufficiency in blood flow to legs
What can be shown to delay onset and progression of complications?
Good metabolic control
How is retinopathy caused?
Small blood vessel damage to the back layer of the eye, the retina leading to progressive loss of vision
How can retinopathy be diagnosed?
Regular eye examinations
How can retinopathy be treated?
Good metabolic control
Early detection
Timely intervention
How can nephropathy be caused?
Damage to small blood vessels in the kidney
What can diabetic kidney disease lead to?
Kidney failure
Death
Leading cause of dialysis and kidney transplant
What are the symptoms of nephropathy?
Usually no symptoms early on Feelings of tiredness Anemia Not think clearly Electrolyte imbalances
How can diabetic kidney disease be diagnosed?
Simple urine test for protein
Blood test for kidney function
How can nephropathy be treated?
Controls of high blood glucose
Control of high blood pressure
Intervention with medication
Restriction of dietary protein
How does diabetes cause neuropathy?
Direct damage by hyperglycaemia
Decreased blood flow to nerves by damaging small blood vessels
What are the symptoms of neuropathy?
Numbness in extremities
Pain in extremities
Impotence
Not recognising cuts and developing foot infections
What is diabetic foot disease?
Ulceration and subsequent limb amputation
Most costly complications of diabetes
Results from both vascular and neurological disease processes
Comprehensive foot programmes can reduce amputation rates by 45-85%
How does diabetes cause cardiovascular disease?
Hyperglycaemia causes atherosclerosis ‘clogging of arteries’
Narrowing causes decreased blood flow to cardiac muscle (heart attack) or brain (stroke)
What are the symptoms of cardiovascular disease?
Chest pain Leg pain Confusion Paralysis Etc.
How can cardiovascular diseases be diagnosed?
Early detection of other risk factors e.g. Smoking High blood pressure High serum cholesterol Obesity
How can cardiovascular diseases be treated?
Controlling risk factors
Controlling blood glucose
What is T2DM?
Chronic metabolic disorder associated with hyperglycaemia caused by impaired insulin secretion and insulin resistance
How is impaired insulin secretion caused?
By pancreatic beta cells dysfunctioning As a result of Lipotoxicity Glucotoxicity Resistance to incretins (intestinal hormones that stimulate insulin secretion)
What results from peripheral organs (liver, muscle, kidneys etc.) becoming insulin resistant?
Reduced glucose uptake from blood
Excessive glucose reabsorption by kidney
Increased gluconeogenesis
What causes insulin resistance?
Impaired insulin receptor signalling as a result of
Genetic abnormalities
Ectopic lipid accumulation
Mitochondrial dysfunction
Inflammation and endoplasmic reticulum stress
What determines the risk of complications?
Severity and duration of hyperglycaemia
What is the action of diabetes drugs?
Target hepatic glucose production Promotes insulin secretion Increases sensitivity to insulin Act on the inverting axis Target intestinal and renal glucose absorption
What percentage of diabetes cases are T2DM?
> 90%
Why might incidence of T2DM have increase in China and India where there is a low prevalence of obesity?
Fat vs. Muscle ratios
Different fat distribution and a greater severity of beta cell failure
