Diabetes Flashcards
Diabetes mellitus- UK prevalence
- 3.6 mil people in the UK- just over double the figure in 1996
- UK orevakence estimated to be 5 million by 2025
- 590,000 people in UK with diabetes but not diagnosed
- Nearly 2 out of 3 adults in UK are overweight or obese
- If current trends persist, 1 in 3 people will be obese by 2034 and 1 in 10 will develop type 2 diabetes
- > 5 million people have non-diabetic hyperglycaemia puuting them at risk of developing type 2 diabetes
- Considerable increase in morbidity and premature death (type 2 die 6-10 years earlier than non-diabetics, with type 1 15 years earlier but this is improving)
Diabetes mellitus- financial cost
- Cost to NHS around 10% of its budget: £1 million an hour or £24 billion a year with the cost of treating rising
- Cost of absenteeism, early retirement and social benefits total at £15.5 billion per annum
- Drugs only account for a portion of costs (£768 million)
Common types of diabetes
TYPE 1
-Absolute insulin deficiency
-Peak incidence between 9-14 years old but can occur at any age
-Of those with diabetes- 10% of adults and 98% of children
TYPE 2
-Relative insulin deficiency caused by disorders of insulin action and insulin secretion (insulin resistance)
-Peak incidence after age of 40, but increase incidence in younger people because of increased obesity
-Of those with diabetes- 90% of adults and 2% of children
-6x more common in south asian than Europeans (also develop at earlier age)
-Pre-diabetes is a metabolic syndrome, linked to obesity, which is a pre cursor to type 2
Gestational- (only diabetic while pregnant, but will go)
-Diabets first diagnosed in pregnancy
diabetic complication
- Most diabetics do not die from metabolic complications (hypoglycemic coma or ketoacidosis from hyperglycaemia, these are not common causes of death)
- Common causes of death is CVS complications (microvascular complications) e.g. heart attack, stroke
- Also high morbidity due to microvascular complications e.g. neuropathy, retinopath , neuropathy also depression and dementia
- Only 40% of people achieving targets recommended to decrease risk of complications
Key diabetic complications
- Stroke
- Eye damage (glaucoma, cataracts)
- MI
- Kidney damage
- Impotence or difficulty passing urine
- Numbness (neuropathy) and reduced blood supply (microvascular)
- Neuropathy is also responsible for erectile dysfunction in men
Diagnosis- symptoms
TYPE 1
-Usually acute
-Weight loss, polyuria, polydipsia (go many times), fatigue and ketoacidosis
TYPE 2
-Often insidious, goes unnoticed for years, with complications being the first obvious symptoms
-Thrist, polyuria, weight loss, chronic skin infections, vaginitis, dry eyes or blurred vision
Diagnosis- HbA1c
- Glycated Hb
- Measures glucose control over past 2-3 months
- WHO recommoned for diagnosis (>48 mmol/mol) in asymptomatic individuals
Diagnosis- glucose measurement
-Random venous plasma glucose conc >11.1 mmol/L
OR
A fasting plasma concentration >7.0mmol/L (Whole blood >6.1 mmol/L)
OR
plasma glucose concentration > 11.1 mmol/L drink 75g anhydrous glucose in oral glucose tolerance test (OGTT)- if plasma glucose is greater than 11 2 hours later than you have diabetes
Diagnosis- glucose measurements
- Diagnosis should never be made based on a finger prick test
- Should be confirmed by an accredited lab based on a venous blood sample (plasthma glucose conc tends to be 10-15% > than whole blood)
- If fasting or random values are not diagonstic, the OGTT should be used
Diagnosis- new tests
C-peptide test
-Released at same time as insulin
-Useful marker of insulin production
GAD Ab test
-Glutamic acid Decarboxylase AutoAb test
-Is body producing Ab that destroy its own GAD cells
-Differentitate between type 1 diabetes or latent autoimmunee diabetes of adulthood (LADA)
Glucose control
- In absence of diabetes, human blood glucose levels are maintained between 4-6 mmol/L
- The tighter the glycaemic control the greater the reduction in microvascular complications, but risk of hypo’s
Monitoring blood glucose control
HBGM (Human blood glucose monitoring)
-Essential for those on insulin
-Educational value
-Overused in Type 2 diabetes not on insulin
Urine dipstick testing (used to test hyperglycaemia)
Venous blood glucose (fasting)
HbA1c (glycated Hb)
-Aim for between 48-59 mmol/mol (6.5-7.5%)
Ketones
- May be presenting feature in type 1
- Can occur if patient forget to take insulin or if there is increase insulin demand e.g. infection, stress
- Insulin lack –> increased breakdown of proteins in order to generate energy
- Measure ketones with urine dip-stick
- When ketones are high or very high known as diabetic ketoacidosis (DKA)
- Ketoacidotic coma can be life-threatening
Microvascular complications
- 80% of diabetics die from cardiovascular disease
- Diabetics are 2-3x more likely to have a stroke compared to non-diabetics
- So essential to have tight control of BP and ChE
Blood pressure measurement
- Sphygmomanometer
- Increasing electronic
- Must be regularly calibrated
- BP target lower in diabetics (<140/80 mmHg)
- Even lower if have kidney, eye or cerebrovascular damage (<130/80 mmHg)
Cholesterol ChE
Full lipid profiles (fasting)
- Total ChE <4 mmol/L
- LDL ChE <2 mmol/L
- HDL ChE
- Triglycerides
Microvascular- nephropathy
- Poor control leads to enlargement of kidneys and initially a higher GFR
- Renal damage causes HTN, HTN causes renal damage
- Single largest cause of end-stage renal failure in westernised countries
- In UK , 1000 diabetic patients start kidney dialysis each year
Nephropathy- annual monitoring
-Microalbuminuria (urinary albumin secretion is 30-300 mg.day) give early warning of diabetic nephropathy
-Measure by either test on 24 hour urine collection or increasingly a single dipstick urine test
-Abnormal ACR (albumin:creatiaine ratio)=
+ACR >2.5 mg/mol for men
+ACR >3.5 mg/mol for women
-Frak proteinuria (300mg per day) marks development of clinical nephropathy
-Measure using urine dipstick
-U&Es
-Must start ACEI or ARB even if they dont have HTN, this will slow nephropathy
-Microvascular- ocular
- Transient visual disturbances due to osmotic changes (hyperglycaemia)
- Retinopathy- Diabetes is the single largest cause of blindness in people of working age
- Cataracts develop earlier in diabetics
- Glaucoma may be primary or secondary to retinopathy
Retinopathy
- Asymptomatic until well advanced
- Classified into stages- background, pre-proliferative, proliferative, advanced and maculopathy
- DUE HIGH GLUCOSE
Ocular disease- annual monitoring
Visual acuity -6m from snellen chart with and without pin-hole Retinal examination -Opthalmoscope -Retinal imaging camera
Microvascular- neuropathy
- Commonest is distal peripheral neuropathy
- Motor neuropathy leading to muscle weakness, wasting and pain
- Automatic neuropathy can affect any part of the sympathetic or parasympathetic nervous systeme.g. erectile dysfunction, bladder instability
The diabetic foot
- Peripheral neuropathy can be painful, but eventually leads to loss of sensation
- Vascular disease leads to ischaemia
- So have a goot rhat doesn’t deal an insult and has poor blood flow, coupled with high glucose levels
- Small injuries rapidly develop into ulcers, infection sets in, followed by gangrene
- Every week, over 135 leg, foot, toe amputations are carried out on people with diabetes in the UK (80% of these are preventable)
Diabetic foot- monitoring
- By patient, check feet daily, encourage use of chiropody service for foot care
- Annually general foot exam, foot pulses (blood flow, doppler) and microfilament (press parts of the foot for feelings)
- If high risk, regular care/assessment by podiatrist
Monitoring for the diabetic patient
- Glycaemic control- blood glucose and HbA1c
- Ketones if necessary
- BP
- ChE
- Renal function- SrCr, microalbumuria, proteinuria
- Eye disease- visual acuity, retinal examination
- Peripheral neuropathy- foot examination, foot pulses and microfilament
- ALL AT LEAST ANNUALLY, some at least 3-6/12
