Type 1 and 2 Diabetes Flashcards
What is the range for normal glucose levels?
3.5-8 mmol/L
Why are there high levels of glucose in diabetes?
- Lack of insulin production (Type 1)
- Insulin resistance (Type 2)
General Overview of Type 1 Diabetes
- Occurs in childhood/ early adult life
- Involves autoimmune destruction of B cells
- Greater environmental influence
- May develop Diabetic ketoacidosis
What are the possible causes of type 1 diabetes?
- Environmental factors that trigger autoimmune destruction
- Lack of vitamin D
- Dietary factors
What are the clinical features of diabetes in general?
- Young age
- 6 week history of polydipsea, polyuria and weight loss
- Ketoacidosis (this is specific to type 1)
- Hyperglycaemia causes appearance of glucose in renal tubule resulting in polyuria as water moves into the renal tubule
- Polyuria causes increased thirst due to the low water content in blood vessels, polydipsea
- Fluid depletion as well as breakdown of protein and fats causes loss in weight
What is Diabetic Ketoacidosis?
Low levels of insulin and high levels of glucagon mean glucose in blood is not taken up into cells. Body compensates for this by increasing gluconeogenesis, lipolysis and proteolysis. These processes result in the formation of ketones, hence acidosis
=> Common precipitating factors of DKA:
- Infection
- Missed insulin doses
- MI
What is the clinical presentation of Diabetic Ketoacidosis?
- Vomiting
- Abdominal pain
- Reduced level of consciousness
- Deep hyperventilation
- Ketotic breath
- Low pH
What are the investigations of Diabetic Ketoacidosis?
- Blood Glucose Levels
≥ 11 mmol/L indicates hyperglycaemia - Blood ketones
> 3 mmol/L indicates ketonemia - Urine dipstick
Positive for glucose - Serum U&E
Elevated due to dehydration
What is the emergency management of Diabetic Ketoacidosis?
- Fluid replacement. IV saline is given first to correct all the water loss
- Insulin replacement. IV insulin given at a rate of 0.1 units/kg/hour until plasma glucose < 15mmol/L, then 5% dextrose is started
- Potassium replacement, to correct hypokalemia which may be caused by the insulin infusion
- Heparin if mobile or conscious
=> Long acting insulin should be continued and short acting insulin should be stopped
=> Cerebral oedema is a serious complication of management due to overcorrection of fluid loss
What is the differential diagnosis of polyuria?
- DM
- DI
- Primary polydipsia
What are the complications of Diabetes?
- Macrovascular
- Microvascular
- Foot complications
What is the main macrovascular complication and what steps can be taken to reduce it?
- Atherosclerosis
=> Risk can be reduced by:
- Hypertension treatment
- Stop smoking
- ACE inhibitor
- Low dose Aspirin
- Statin treatment
What are the main microvascular complications in diabetes?
- Affect kidneys, eyes and nerves
- Nephropathy
- Retinopathy
- Neuropathy
What are the different types of neuropathies?
=> Symmetrical sensory neuropathy
- Cannot be treated
- Glove stocking syndrome
=> Acute painful neuropathy
- Burning/ crawling pains in lower limb
=> Mononeuritis
- One or more nerves affected
=> Amyotrophy
- Painful muscle wasting, asymmetrical
=> Autonomic neuropathy
- Postural hypotension
Diabetic foot, screening and management
=> Presentation:
- Neuropathy
- Ischaemia
- Complications: calluses, ulcerations, Charcot’s arthropathy
=> Screening:
- Screening for ischaemia involves palpating pulses
- Screening for neuropathy involves using 10g monofilament on sole of foot
=> Management:
- Anyone who presents with anything other than calluses alone classes as moderate or high risk, and should be followed up regularly by the local diabetic foot centre
What are the investigations in suspected Diabetes?
Main test - fasting glucose
≥ 7 mmol/L indicates diabetes
Random plasma glucose
≥ 11.1 mmol/L indicates diabetes
Oral Glucose Tolerance Test - Gold Standard
Hb1Ac
42-47 mmol/L is pre-diabetic
≥ 48 mmol/L is diabetes
To make the diagnosis, HbA1c and fasting glucose are both tested in that order
What is the criteria for successful management of diabetes?
- Good glycemic control
- Good regular exercise, stop smoking and drinking alcohol
- Treat hypertension and hyperlipidemia
- Regular checks
What does the diet plan for diabetes involve?
- Low sugar
- High starch
- Artificial sweeteners
- Low fat
- Include protein
What is the specific management of type 1 diabetes?
- Receptors still respond to insulin, the issue is insulin insufficiency
- External source of insulin taken
- Check glucose levels 4 times a day before meals
Target should be 5-7 mmol/L on waking and 4-7 mmol/L before meals
- Monitor HbA1c every 3-6 months, aim for ≤ 48
- Metformin recommended in those with BMI ≥ 25
=> Types of insulin:
- BD biphasic regimens (twice daily premixed insulin)
- QDS regimens (before meals ultra fast + bedtime long acting)
- Once daily (before bed long acting insulin)
Overview of type 2 diabetes
- Older population
- Obesity is the biggest risk factor
- Mainly due to insulin resistance and end stage B cell dysfunction
- Greater genetic influence (HLA linked)
- May develop hyperosmolar hyperglycaemic state (HSS)
What is the clinical presentation of hyperosmolar hyperglycaemic state?
- Dehydration
- Decreased conciousness
- Normal pH as no ketoacidosis
What are the names of the drugs used in the management of type 2 diabetes
- Conservative management involving diet and lifestyle change
If conservative management not working, start medication
METMORFIN SULFONYLUREAS GLITAZONES DPP-4 INHIBITORS (GLIPTINS) SGLT-2 INHIBITORS
What drugs induce diabetes?
- Corticosteroids
- Anti-HIV drugs
- Antipsychotics
How do you diagnose type 2 diabetes?
If patient is symptomatic:
- Fasting glucose ≥ 7 mmol/L
- Random plasma glucose ≥ 11.1 mmol/L
- HbA1c ≥ 48
If patient is asymptomatic, above criteria must be true for 2 separate occasions
What is impaired fasting glucose and impaired glucose tolerance?
6.1 ≤ Fasting glucose (mmol/L) < 7 implies Impaired Fasting Glucose (IFG)
People with Impaired Fasting Glucose are offered a OGGT. 7.8 ≤ OGTT < 11.1 then the patient does NOT have diabetes, they have Impaired Glucose Tolerance
=> Impaired Glucose Tolerance
Fasting glucose < 7 mmol/L
7.8 ≤ OGTT 2 hour value < 11.1 mmol/L
In what conditions or circumstances are HbA1c readings not useful?
- Presence of abnormal haemoglobin
- Altered lifespan of red blood cells
- Recent blood transfusions
- Anaemia
- Ethnicity
- Ageing
- All children and young people
- Type 1 Diabetes
- Symptoms of diabetes < 2 months
- Acutely ill patients
- If on medications that cause hyperglycaemia
- Acute pancreatic damage
- Pregnancy
=> Cases where RBC lifespan is lower:
- G6PD deficiency
- Sickle cell anaemia
- Hereditary spherocytosis
=> Cases when RBC lifespan increased:
- Splenectomy
- Iron defieincy anaemia
- Vitamin B12/folate deficiency
What is the specific management of type 2 diabetes in those where Metformin is not contraindicated?
- Lifestyle and diet
- First line is Metformin
=> HbA1c > 58 mmol/L
Meformin + Gliptin OR Metformin + Sulfonylurea OR Metformin + Pioglitazone OR Metformin + SGLT2 inhibitor
=> HbA1c > 58 mmol/L
Metformin + Gliptin + Sulfonylurea
OR
Metformin + Pioglitazone + Sulfonylurea
OR
Metformin + SGLT2 inhibitor + Sulfonylurea
OR
Metformin + SGLT2 inhibitor + Pioglitazone
=> If triple therapy is not effective, contraindicated or not tolerated AND BMI ≥ 35:
Metformin + Sulfonylurea + GLP-1 mimetic
If after dual therapy there is no improvement in HbA1c levels and they remain above 58, insulin infusion may be considered rather than using the oral drugs
What is the specific management of type 2 diabetes in those with Metformin contraindication?
First line - Gliptin OR Sulfonylurea OR Pioglitazone
=> HbA1c > 58 mmol/mol
Gliptin + Pioglitazone OR Gliptin + Sulfonylurea OR Sulfonylurea + Pioglitazone
=> HbA1c > 58 mmol/mol
- Insulin infusion
What are the risk factors of gestational diabetes?
- Obesity
- Previous gestational diabetes
- Previous baby birthweight ≥ 4.5kg
- Family history
- South asian, Black, Arfo-Caribbean or Middle Eastern ethnicity
How is gestational diabetes diagnosed?
Fasting plasma glucose ≥ 5.6 mmol/L
OR
2-hour plasma glucose ≥ 7.8 mmol/L
What complication is type 2 diabetes associated with?
- Hyperosmolar Hyperglycaemic State
- Occurs due to insulin deficiency and increased counter regulatory hormones, but the small amount of insulin is high enough to prevent ketonemia
What are the clinical features of hyperosmolar hyperglycaemic state?
- Insidious onset
- Hyper-coagulable state
- Confusion
- Vomiting
- Venous thrombosis
What is the management of Hyperosmolar Hyperglycaemic State?
- Rehydration
- Prophylactic heparin
- Gentler insulin regime
- More agressive broad spectrum antibiotic regime
What are the 4 stages of Diabetic Retinopathy?
=> Background Retinopathy
- Microaneurysms
- Haemorrhages
- Hard exudates
=> Pre-proliferative Retinopathy
- Cotton wool spots
- > 3 blot haemorrhages
- Venous beading/looping
- Deep/dark cluster haemorrhages
=> Proliferative Retinopathy
- Retinal neovascularisation
- Fibrous tissue forming anterior to retinal disc
=> Maculopathy:
How is Diabetic Retinopathy prevented?
- Annual retinal screening
- Referral to opthalmologist with proliferative changes
How is Diabetic Nephropathy prevented?
- Strict glycaemic and BP control
- Proteinuria monitored at each clinical appointment and microalbuminuria monitored annually
What is microalbuminuria?
- Albumin in urine
- Albumin : Creatinine Ratio > 2.5 (men)
- Albumin : Creatinine Ratio > 3.5 (women)
=> If > 3 then ACEi, Ang II blockers or Spirolactone helps protect kidneys
What are the affects of Diabetic Neuropathy?
- Neuropathic ulcers
- Charcot arthropathy
- Paraesthesia
- Impotence
- Diarrhoea/constipation
- Orthostatic hypotension
What is Mature Onset Diabetes of Young? (MODY)
- Characterised by the development of Type 2 diabetes in those < 25
- Autosomal dominant condition
- MODY 3, MODY 2 and MODY 5 are the main types
=> MODY 3:
- Defect in HNF-1 alpha gene
- Associated with increased risk of HCC
=> MODY 2:
- Defect in glucokinase gene
=> MODY 5:
- Defect in HNF-1 beta gene
- liver and renal cysts seen
What is Latent Autoimmune Diabetes of Adults? (LADA)
- Small group of patients that develop problems later in life
- Form of Type 1 Diabetes
MICA of Metformin
=> MOA
- Reduces hepatic glucose output and increases glucose uptake and use by skeletal muscles
- Activation of AMP kinase
=> Indications:
- First choice in Type 2 Diabetes
=> Contraindications:
- Renal impairment
- Liver impairment
- Acute alcohol intoxication
- Chronic alcohol abuse
=> Adverse effects:
- GI upset
- Lactic acidosis
MICA of Sulfonylureas and examples
Eg. Gliclazide
=> MOA:
- Block K channels of B cells
- Stimulate insulin secretion
=> Indications:
- Combination with metformin for T2D
- Single use when Metformin contraindicated
=> Contraindications:
- Renal impairment
- Hepatic impairment
- Increased risk of hypoglycaemia
=> Adverse effects:
- GI upset
- Increased weight
- Hypoglycaemia
- Hyponatremia
- Rare hypersensitivity reactions
MICA of Glitazones and examples
Eg. Pioglitazone, Rsoiglitazone
=> MOA:
- Increase sensitivity to insulin
=> Contraindications:
- Past or present Congestive Cardiac Failure
- Osteoperosis
- Obesity
- Oedema
=> Adverse effects:
- Hypoglycaemia
- Fractures
- Fluid retention
- Increased LFTs
MICA of DPP-4 inhibitors and examples
DPP-4 inhibitors = Gliptins
Eg. Sitagliptin
=> MOA:
- Block action of DPP-4, hormone which destroys hormone incretin
=> Adverse effects:
- Increased risk of pancreatitis
MICA of SGLT2 inhibitors and examples
Eg. -gliflozins
=> MOA:
- Inhibit reabsorption of glucose in kidneys
=> Adverse effects:
- UTIs
