Type 1 and Type 2 diabetes Flashcards
What is type 1 diabetes?
inability to produce/secrete insulin due to autoimmune destruction of the beta-cells in the pancreatic islets of Langerhan.
What is type 2 diabetes?
a combination of peripheral insulin resistance and inadequate secretion of insulin. It is strongly associated with obesity and the metabolic syndrome.
At what age does type 1 diabetes develop?
typically develops in children and adolescents
But condition can develop at any age
Which genes are associated with diabetes development?
HLA-DR3- DQ2
HLA-DR4-DQ8
Which other autoimmune conditions is type 1 diabetes associated with?
Autoimmune thyroiditis
Graves disease
Coeliac disease
Addison’s disease
Pernicious anaemia
Describe the hypotheses behind diabetes development - combination of genetic and environmental factors
genetically susceptible individuals may develop autoantibodies that target the beta-cells in response to an external trigger (e.g. viral infection).
Which autoantibody is most commonly found in those with type 1 diabetes?
anti-glutamic acid decarboxylase (anti-GAD) antibody
Where is anti-glutamic acid decarboxylase (anti-GAD) antibody found?
enzyme found within beta cells of the pancreas
What is the normal range for blood glucose?
3.5-8.0 mmol/L.
What are the consequences of decreased insulin concentration in the body?
More glucose is produced by the liver -
Increases glycogenolysis and gluconeogenesis
Decreased glucose uptake
Increased lipolysis
Decreased glucose uptake in adipose tissue and muscle
Decreased protein synthesis and increases protein degradation (increased fat and muscle break down)
Reduced peripheral uptake of glucose to use for energy. Weight loss occurs
What happens to the blood sugar when enough insulin is not being produced?
hyperglycaemia - high blood sugar
Which acid base disorder is associated with type 1 diabetes and how does it develop?
metabolic acidosis
Body is not obtaning enough enegery as glucose is not being taken up peripheraly and being used for energy
Fatty acids are taken up into hepatocytes and converted into ketone bodies.
Ketone bodies are released back into the circulation and utilised for energy in the form of ATP.
The development of ketosis leads to metabolic acidosis
What are the features of Latent-onset autoimmune diabetes in adults?
Type 1 diabetes later in life
autoimmune destruction of beta cells
tends to have a gradual onset.
patients who develop diabetes in adult life with associated ketosis, weight loss, low BMI and family history of autoimmune disease.
What are the signs and symptoms of type 1 diabetes?
Symptoms
- lethargy
- polyuria
- polydipsia
- weight loss
- Vomiting
Signs
- Mild-moderate dehydration (dry skin, dry mucous membranes, reduced skin turgor)
- BMI < 25
How is type 2 diabetes diagnosed?
classical clinical features are found in the presence of a raised random blood glucose level.
Which further tests are conducted on patients suspected with Latent-onset autoimmune diabetes in adults?
c-peptide, genetic testing
There are 5 main aspects to the management of type 1 diabetes - name them
Insulin use and regimes
Blood glucose monitoring
Treatment targets
Monitoring for
complications
Education
List the different types of insulin used in the treatment of type 1 diabetes
Rapid acting - Novorapid, Lispro
Short acting - Humulin R
Intermediate acting - Humulin I or N
Mixed - Humulin M3
or Humulin 70/30: Mix of short and intermediate-acting insulin
Long acting - Lantus, Levmir
Biphasic - mixture of rapid and intermediate eg Novomix 30
What are the 3 main insulin regimes used in patients with type 1 Diabetes?
Basal-bolus regime - rapid- or short-acting insulin before meals and a long-acting preparation for basal requirements.
One, two, or three injections per day regime: - traditionally a biphasic regime with the use of both short-acting and intermediate-acting insulin as separate injections or a mixed product.
Continuous insulin infusion via a pump - supplies rapid- or short-acting insulin. It may be used in patients who are experiencing troubling hypoglycaemic episodes with multiple daily injections regimes.
Which of the insulin regimes is used for newly diagnosed patients?
Basal-bolus regime
Which of the insulin regimes is used for patients having troubling hypoglycaemia episodes?
Continuous insulin infusion via a pump
How often are people with hypoglycaemia required to monitor there blood glucose in a day? When during the day can it be monitored? What is the target blood glucose at monitoring period?
At least four times a day
On waking: fasting blood glucose 5–7 mmol/L
Before meals: blood glucose 4–7 mmol/L
Post meals: test after 90 minutes, blood glucose 5–9 mmol/L
Can also measure it before bed instead of in the morning
Under which conditions may a patient be required to monitor there blood glucose more than 4 times daily
porting activities, pregnancy and in those with hypoglycaemic episodes.
What is used to monitor the long term control of blood glucose? How often should the test be conducted?
HbA1c - glycated haemoglobin, indicative of the average blood glucose over 3 months
It should be repeated every 3-6 months to assess glycaemic control.
What should the target HbA1c be? When may a higher target be required?
HbA1c < 48 mmol/L (6.5%).
Higher threshold?
hypoglycaemic episodes, occupation and co-morbidities.
How often should patients obtain a diabetic complications review. What is assessed during these reviews?
At least once a year- more often if required
Assessment of injection site - fat accumilation
Retinopathy review - screening
Nephropathy review - renal function (eGFR) and albumin:creatinine ratio (ACR)
Diabetic foot review (neuropathy) - full examination including footwear, monofilament assessment of neuropathy, vascular assessment +/- dopplers.
Cardiovascular risks - optimisation of blood pressure, lipids, weight, smoking and others
Thyroid disease - Blood tests
Which Retinopathy complications are associated with diabetes?
Non prolifertaive - Dilation of the retina veins and microaneurysms which can cause internal hemorrhaging and oedema in the retina. Oedema in the central retina is the main cause of vision loss in this case
- Dot and blot haemorrhages
- Hard exudates
- Cotton wool spots
- Venous beading (pre- proliferative)
Proliferative
Fragile, new blood vessels form near the optic disk and grow on the vitreous chamber and elsewhere in the retina. They can bleed, reduce vision and lead to separation and detachment of areas of the retina
- new vessels at the disc and elsewhere
- fibrosis
- traction retinal detachment
Maculopathy
- Exudates
- Oedema
Which Nephropathy complications are associated with diabetes?
Disease of the kidney involving damage to the blood vessels
in the glomerulus
is characterised by proteinuria, glomerular hypertrophy,
decreased glomerular filtration and renal fibrosis
First sign = microalbuminuria, which can be assessed with an albumin:creatinine ratio (ACR). An ACR 3 - 30 mg/mmol is suggestive of microalbuminuria
Which neuropathy complications are associated with diabetes?
Damage to the nerve fibres and blood vessels supplying nerves
- Peripheral
It causes pain or loss of feeling in the hands, arms, feet, and legs
It causes pain in thighs and hips and weakness in legs
- It can cause changes in digestion, bowel (gastric paresis) and bladder control problems, and erectile dysfunction
It can affect any nerve in the body and it causes pain or weakness
Symmetrical polyneuropathy: typically a peripheral neuropathy that occurs in the leg secondary to loss of vibration, pain and temperature sensation.
Mononeuropathy: damage to a single cranial or peripheral nerve (e.g. third nerve palsy).
Diabetic amyotrophy: a spectrum of disease affecting the lumbosacral plexus leading to symmetrical pain, weakness and wasting in the proximal muscles of the leg.
Autonomic neuropathy: a spectrum of conditions related to damage of the autonomic nervous system, which can effect multiple systems.
Which Cardiovascular complications are associated with diabetes?
- Increases risk of atherosclerosis plaque formation
- Tissue nutrient and oxygen supply to heart and brain and extremities is compromised
- Cerebrovascular disease (stroke)
- Heart Disease (Myocardial infarction, congestive heart failure)
- Peripheral vascular disease (ulceration, gangrene and amputation
In the context of type 1 diabetes what does the term sick day rules mean?
Understanding what to do during intercurrent illnesses is essential in patients with T1DM to prevent poor glycemic control and potential ketoacidosis.
List 5 sick day rules
Continue insulin therapy, alterations may be required, advice from a specialist may be sought
Increase frequency of blood glucose monitoring
Consider ketone monitoring
Maintain good hydration and when possible a normal meal pattern, meals may be replaced by carbohydrate based drinks
Seek urgent medical attention if unable to tolerate oral intake, drowsy or sustained vomiting
Which Diabetic foot problems /complications are associated with diabetes?
Due to loss of sensation and poor blood supply, patients are at risk of a number of complications including diabetic ulcers, secondary infection (e.g. cellulitis, osteomyelitis), skin necrosis and eventually amputation.
Charcot’s joint - results from loss of sensation and subsequent repeated micro-trauma to the foot. Typically mid foot. Microtrauma in the presence of poor peripheral blood flow leads to remodelling, swelling and distortion of the whole joint.
Which skin infections are those with diabetes prone to?
staphylococcal skin abcesses, oral or genital candidiasis
Which symptoms are associated with typ2 2 diabetes?
- polyuria
- polydipsia
- nocturia
- weight loss
- fatigue
- blurred vision
- pruritis
- recurrent urinary or genitourinary infections
Name the 4 tests used in the diagnosis of diabetes
Fasting plasma glucose (FPG)
Random plasma glucose (RPG)
75 gram oral glucose tolerance test (OGTT)
Haemoglobin A1c (HbA1c, glycated haemoglobin)
What is the difference in diagnosiing diabetes in someone with symptoms and in someone without?
for an individual who has no symptoms, two diagnostic tests are required (eg 2x
FPG, or HbA1c, but only one abnormal OGTT is required)
One diagnostic test is enough to diagnose diabetes for someone with symptoms
What is the difference in diagnosing diabetes in someone with symptoms and in someone without?
For an individual who has no symptoms, two diagnostic tests are required (e.g. 2x
FPG, or HbA1c, but only one abnormal OGTT is required)
One diagnostic test is enough to diagnose diabetes for someone with symptoms
For each test used in diagnosing diabetes, state which values are normal, abnormal, and indicative of impaired glucose tolerance (IGT)
Fasting plasma glucose
N = <6.0 DM = >7.0 IGT = <7.0
Impaired fasting glucose = 6.1-6.9
Random blood glucose
N = <7.8 DM = >11.1
HbA1c
N = <42 (5.9%) DM = > 48 (6.5) IGT = 42-47 (6.0-6.4)
2H plasma glucose
N = <7.8 DM = >11.1
IGT = 7.8-11.0
IFG = <7.8
For each test used in diagnosing diabetes, state which values are normal, abnormal, and indicative of impaired glucose tolerance (IGT)
Fasting plasma glucose
N = <6.0 DM = >7.0 IGT = <7.0
Impaired fasting glucose = 6.1-6.9
Random blood glucose
N = <7.8 DM = >11.1
HbA1c
N = <42 (5.9%) DM = > 48 (6.5) IGT = 42-47 (6.0-6.4)
2H plasma glucose (OGTT)
N = <7.8 DM = >11.1
IGT = 7.8-11.0
IFG = <7.8
Which endocrine disease can cause diabetes?
Acromegaly - excess growth hormone
Cushing’s syndrome - excess cortisol
Glucagonoma - excess glucagon
Phaechromocytoma - excess catecholamines
Hyperthyroidism - excess thyroid hormone
Conn’s syndrome- excess aldosterone
Which drugs can cause diabetes?
Glucocorticoids
b-blockers
Thiazide diuretics
Tacrolimus (used in transplantation – may cause “New Onset Diabetes
after Transplantation” [NODAT])
Atypical anti-psychotics – eg. olanzapine, risperidone, clozapine
Which infections can cause type 2 diabetes?
Congenital rubella
Cytomegalovirus
others
What does the term glucose toxicity mean with regards to type 2 diabetes?
When hyperglycaemia enhances insulin resistance and b- cell failure (unable to produce as much insulin) in type 2 diabetes
High glucose = poorer B cell function so less insulin secretion
What are thrifty genes?
Genes,which favour that favour fat storage and / or insulin resistance help us in times of famine
May be overly activated in diabetes
How do fat cells contribute to insulin resistance?
pro-inflammatory cytokines from adipocytes contribute to insulin resistance
In type 2 diabetes, what happens to the mass of beta cells and alpha cells?
b-cell mass is relatively preserved
a-cell population increased – leads to excess glucagon relative to insulin
Later on with type 2 diabetes, which protein is deposited in the pancreas which lings diabetes to dementia?
Amyloid peptide deposition in the pancreatic islets occurs late in the disease
List the 5 main factors associated with metabolic syndrome?
- Central Obesity
- Low HDL Concentration
- High Triglyceride
- High Blood pressure
- increased Fasting glucose
Which individuals should be screened for type 2 diabetes?
- Over weight people
- Strong family history of diabetes
- History of gestational diabetes
- Ethnic minorities
▪ South Asian – 6x increased risk
▪Afro-Caribbean – 2x increased risk
Individuals with known
vascular disease
- Coronary Heart Disease,
- Peripheral Vascular Disease,
- Cerebrovascular disease
- Patients on steroids / atypical anti-psychotic therapy / transplants
Unexplained foot ulcers / recurrent candida / skin abscesses
When can using HbA1cot diagnose diabetes be problematic?
conditions interrupting erythropoiesis (e.g. EPO use, iron-deficiency),
haemoglobin structure issues (e.g. haemoglobinopathies),
glycation issues (e.g. CKD, alcoholism),
red cell survival (e.g. haemolysis, splenectomy)
What are the 3 main injection sites for insulin? List in order of fastest absorption site to slowest
Abdomen
Thighs
Buttocks
