Diabetes Flashcards
What is Diabetes Mellitus?
a group of metabolic diseases in which ther are high blood sugar levels over a prolonged period
What are some symptoms of a high blood sugar?
frequent urination
increased thirst
increased hunger
Name some acute complications of diabetes?
- diabetic ketoacidosis
- non-ketotic hyperosmolar coma
- death
List some long-term complications of diabetes
- heart disease
- stroke
- chronic kidney failure
- foot ulcers
- damage to the eyes
What is the essential cause of diabetes?
- pancrease not producing enough insulin
OR - body not responding properly to the insulin that is produced
What are the 3 main types of diabetes mellitus?
T1DM
T2DM
Gestational diabetes
What is the cause of T1DM? Briefly state the pathophysiology
Causes is unknown
results from the pancreas failure to produce enough insulin
T1DM was previously referred to as…
Juvenile diabetes
Insulin-dependent diabetes mellitus
T2DM patients can also become dependent on insuling hence why this name is no longer used/appropriate
The alpha cells in the islets of langerhans produce …
glucagon
The Beta cells of the islet of langerhans produce…
insulin
The delta cells of the islets of langerhans produce…
somatostatin
What is the pathophysiology of T2DM?
begins with insulin resistance, a condition in which cells fail to respond to insulin properly
T2DM was previously referred to as …
- non insulin depenent DM
- adult onset diabetes
T2DM patients can eventually become dependent on insulin
What is the primary cause of T2DM?
excessive weight and not enough exercise
Who does gestational diabetes mainly affect?
pregnant women without a previous history of diabetes
Compare and contrast features of T1DM and T2DM
T1DM:
* Sudden onset
* onset mostly in children
* thin/normal body size
* ketoacidosis is common
* autoantibodies are usually present
* endogenous insulin is either low or absent
* 50% concordance in identical twins
* 10% prevalence
T2DM:
* gradual onset
* onset mostly in adults
* ketoacidosis is rare
* autoantibidies are absent
* endogenous insulin may be normal, decreased or increased
* 90% concordance in twins (highlights genetic risk)
* 90% prevalence
What are the main symptoms of diabetes?
Central:
* polydipsia (thirst)
* polyphagia (loss of glucose; eating more to compensate for glucose loss)
* lethargy
* stupor
* headache
Systemic:
* weight loss
Respiratory:
* Kusssmauls breathing- hyperventilation
Breath:
* smell of acetone- fruity smell of acetone
Eyes:
* blurred vision
Gastric:
* nausea
* vomiting
* abdominal pain
Urinary:
* polyuria
* glycosuria (glucose in urine)
Vasular:
-slow healing of cuts
Skin:
-itchy skin
What is ketoacidosis?
this is the result of a insulin resistance/lack of insulin; where the body is unable to use sugars fo energy and thus fat is used instead. Chemicals called ketones are a biproduct of the break down of fat
Ketones cause blood to become more acidic leading to respiratory compensation to breathe out - hyperventilation
What ate the classic symptoms of untreated diabetes?
- weight loss
- polyuria
- polydipsia
- polyphagia
What is the effect of prolonged high blood glucose on the eye?
leads to glucose absorpion in the lens of the eye
this leasds to changes in the shape of the lens resulting in vision changes
A number of skin rashes that can occur in diabetes are collectively known as…
diabetic dermadromes
The major long term complications of diabetes relates to damage to __________.
blood vessels
Diabetes doubles the risk of ________ disease
cardiovascular
includes:
CAD
macrovascular disease (stroke)
Peripheral vascular disease
75% of deaths in diabetes are due to coronary artery disease (affects blood vessels that supply the heart)
The primary complication of diabetes is due to damege in small blood vessels. Give examples of tissue/organs most likely to be affected by small vessel damage
- eye
- kidney (glomerulus)
- nerves (have their small blood supply)
What is the cause of diabetic retinopathy? What is the consequence of this condition?
damage to blood vessels in the retina of the eye
gradual vision loss, blindness
What are the consequences of diabetic nephropathy?
- tissue scarring
- urine protein loss (frothy urine)
- eventually CKD, sometimes requiring dialysis or kidney transplant
What is the most common complication of diabetes?
diabetic neuropathy
What are the symptoms of diabetic neuropathy?
- numbness
- tingling
- pain
- altered pain sensation which can lead to damage to the skin
Diabetes related foot problems- diabetic foot ulcers; difficult to treat often requiring amputation
What is the result of proximal diabetic neuropathy?
- painful muscle wasting
- muscle weakness
What is the function of insulin?
principle hormone that regulates the uptake of glucose from the blood into the cells of the body especially liver, adipose tissue and muscle
Insulin acts via what receptor in smooth muscle cells?
Insulin like growth factor receptor 1
IGF-1 receptors
What are the main ways in which the body obtains glucose?
- intestinal absorption of food
- breakdown of glycogen
- gluconeogenesis
What is glycogen?
storage form of glucose found in the liver
What is gluconeogenesis?
generation of glucose from non carbohydrate substrates in the body
What are the physiological effects of insulin on the body?
- inhibits the breakdown of glycogen or the process of gluconeogenesis
- stimulates transport of glucose into muscle and fat cells
- stimulate storage of glucose in the form of glycogen
What is the effect of low glucose levels in the body?
- glycogen breakdown
- gluconeogenesis
- decreasesd insulin release from beta cell
- release of glucagon from alpha cells
What is the physiological effect of glucagon on the body?
- stimulates break down of glycogen
- increased blood glucose levels
- can stimulate gluconeogenesis ?
What is the net effect of persitently high blood glucose levels (include biochemical effects)?
- poor protein synthesis
- breakdown of fat storage (ketoacidosis)
- kidneys will reach a threshold of reabsorption of glucose; therefore glycosuria
- increases osmotic pressure of urine- polyuria- increased loss of fluids
- loss of fluids will be replaced osmotically by water held in body cells and other body compartments (dehydration)
- dehydration is then compensated for with polydipsia
What is T1DM characterised by?
the loss of insulin producing beta cells in the islet of langerhans in the pancreas
leads to insulin deficiency
T1DM can be classified as either ________ or ____. State the more dominant class.
idiopathic (unknown)
immune mediated
Majority of T1DM is of the immune mediated nature
Briefly describe what the immune mediated form of T1DM entails
A T-cell mediated attack which leads to the loss of beta cells and thus insulin
In T1DM, unlike T2DM, what remains unaffected?
sensitivity and response to insulin
there just isn’t enough insulin being produced
There is a genetic component to T1DM. What genes have been implicated in the risk of developing diabetes?
HLA genotype
In genetically susceptible people, the onset of diabetes can be triggered by one or more environmental factors such as …
viral infection
diet
T2DM is characterised by insulin resistance. What does this mean?
this is when there is a defective resoonse of body tissues to insulin; this is believed to involve the insulin receptors
What is th predominant abnormality in the early stage of T2DM?
reduced insulin sensitivity
What are the main causes of T2DM?
lifestyle factors (diet, exercise, obesity, stress)
genetics
Outline dietary factors which contribute to the development of diabetes
- sugar-sweetened drinks
- types of fats in diet
- eating lots of white rice may increase the risk of diabetes
- lack of exercise beliebe to cause 7% of cases
What types of fat increased the risk of T2DM?
Saturated fats
Trans fatty acids
What kinds of fats decrease the risk of developing T2DM?
polyunsaturated fats
monounsaturated fats
What are the causes of gestational diabetes?
- relatively inadequate insulin secretion
- inadequate responsiveness to insulin
GD may improve or disappear after delivery
What are the management strategies for gestational diabetes ?
- dietary changes
- blood glucose monitoring
- in some cases, insulin may be required
What are the risks of gestational diabetes?
- macrosomia (high birth weight)
- congenital heart defects
- central nervous system abnormalities
- skeletal muscle malformations
Briefly describe the caues of macrosomia in GD
high blood glucose levels in mother
brings extra glucose to the baby
causes the baby to put on weight
Respiratory distress syndrome is a complication observed in children who’s mothers have GD. Briefly describe the pathology of this
- increased glucose levels in baby
- this leads to increased levels of insulin in babys blood (may come from mother who is only insulin resistant?)
- insulin may inhibit surfactant production by type II alveolar cells
*
surfactant- lipoprotein secreted by type II cells
increased the surface tension in the alveoli when no air is present
keeps them open
Infanst of mothers with GD are at an increased risk of hyperbilirubinaemia. True or false
True
may result from increased red cell destruction
Perinatal death is a severe consequence of GD. Why does this occur?
due to poor placental perfusion due to vascular impairment
(diabetes damages microvasculature)
When is labour induction indicated in GD?
when there is decreased placental function
When are c-sections indicated for GD patients?
- marked fetal distress
- risk of injury associated with macrosomia such as shoulder dystocia
How can diabetes increase the risk of periodontal disease?
- microangiopathy (diseased microvasculature) can alter antigenic challenge -infection?
- altered cell mediated immune response and impaired neutrophil chemotaxis- ability to fight off infection
- increased calciumand glucose leads to plaque formation
- increased collagen breakdown (accumulation of MMPs, metalloproteinases)
gingiva is 60% collagen
increased presence of MMPs leads to break down of gingiva
impaired angiogenesis is caused by action of MMPs in diabetes
What are some oral complications of diabetes?
- xerostomia is common reason is unclear
- tenderness, pain and burning sensation of tongue
- enlargment of parotid gland with sialosis
- increased caries prevalence (xerostomia, glucose)
- hyperglycaemia shows a positive association with dental caries
What is sialosis?
enlargment of major salivary gland
normal gland tissue is replaced by adipose tissue
There is an increased risk of infection in patients with diabetes. Briefly outline some reasons for this
- reason unknown but macrophage metabolism is altered with inhibition of phagocytosis
- peripheral neuropathy and poor peripheral circulation
- immunological deficiency
- high sugar medium
- decreased production of antibodies
- candical infections more common, adding to effects with xerostomia
increased risk of dental infections
There is delayed wound healing in patients with diabetes. Why is this? What is an oral implication of this
- due to microangiopathy (damaged microvasculature) and utilisation of protein for energy, may retard the repair of tissues - gluconeogenesis will divert use of proteins which could be otherwise used for wound healing
Delayed wound healing increase the prevalence of ____________ in dentistry
dry socket
What are the side effect of drugs such as glicazide or chlopropamide used to treat diabeters?
-sulfonylurea (stimulate release of insulin from pancreas)
-sulfonylureas may be associated with a lichenoid reaction
Patients with diabetes can present with pulpitis for no obvious reasons. Why is this the case?
nerve plexuses that occupy the pulp are at risk of inflammation
there is also vascular degeneration; vessels that supply the nerves in the pulp are damanged
Oral ulcers are a result of …
a breakdown in the epithelial lining
List the dental management considerations that should be made for a diabetic patient
MH:
* glucose levels
* frequency of hypoglycaemic episodes (consequence of medication)
* medication, dosage and times
* consultation
Scheduling of visits:
* morning appointments
* do not coincide with peak activity (hypoglycaemia)
Diet
* ensure patient has eaten normally and taken medications as usual
Blood glucose monitoring:
* should be measured before the start of appointment
Prophylactic antibiotics:
* [at an increased risk of infection]
* establish infection
* pre-operation contamination wound
* makor surgery
What considerations should be made for diabetic patients during dental treatment?
- hypoglycaemic attack
- hyperglycaemia
What considerations should be made for diabetic patients after dental treatment?
- infection control
- dietary intake
- medication e.g. aspirin
What are salicylates contradinidcated for prescription to diabetic patients in the dental surgery?
this is because they increase insulin secretion and sensitivity
As well as diabetic medication, this can lead to hypoglycaemia in patients
What is the cause of neurological symptoms of hypoglycaemia?
the brain can only access glucose for metabolism
does not metabolise proteins or fats
What are the initial signs of hypoglycaemia?
mood changes
decreased spontaneity
hunger
weakness
What are the signs of hypoglycaemia (after initial signs)?
Fight/flight
sweating
incoherence
tachycardia
Hypoglycaemia can result in…
unconsciousness
hypotension
hypothermia
seizures
coma
death
If a patient is conscious and able to swallow, how would you manage a hypoglycaemic event?
- sugar drink, 150ml carbonated drin
- 2 tea spoons of sugar in water
- orange squash
- repeat 10-15 minutes
If a patient is drowsy, how would you manage a hypoglycaemic event?
- sublingual carbohydrate gel
- hypostop gel (10g) glucose
- repeat 10-15 minutes
If a patient is very drowsy or unconscious, how would you manage a hypoglycaemic attack?
- glucagon 1mg IM/subcutaneous + sugary drink
- check blood glucose rises above 5.0mmol in 10 minutes
If a patient remains unconscious and unresponsive to glucagon in 2-3 minutes, what should you do?
- call ambulance
- monitor airway and pulse
In a severe hyperglycaemic event, ketoacidosis may develop. What symptoms accompanies this condition?
- nausea
- vomiting
- abdominal pain
- acetone odor
How would you manage an hyperglycaemia in an emergency?
- seek medical intervention immediately
- insulin administration
- while in emergency give glucose first (difficult to differentiate between hypo and hyper); small amount is unlikely to cause significant harm
How is diabetes diagnosed?
- fasting plasma glucose levels >/=7mmol/L /126mg/dL
- plamsa glucose >=11mmol/L(200mg/dL) 2 hours after 75g oral glucose load in a GTT
- symptoms of a high blood sugar and casual plasma glucose
- glycated hemoglobin (HbA1c) >/= 48mmol/mol
*
GTT- glucose tolerance test
What is an oral glucose tolerance test?
measures the bodys ability to metabolise glucose
When is an OGTT most commonly done?
to check for gestational diabetes
How is an OGTT performed?
- pt is asked to fast for 8-12 hours
- blood is drawn to test the fasting blood glucose level
- glucose drink is administered
- blood samples drawn for 3 times with a time interval of 1 hour
What amount of glucose should be administered in a standard OGTT?
75/100 grams of glucose
What is the OGTT result of a patient withoit diabetes?
Fasting value <6mmol/L
at 2 hours, under 7.8mmol/L
What is the OGTT result for people with an impaired glucose tolerance?
Fasting value- 6.0-7.0mmol/L
at 2 hours 7.9-11.0mmol/L
What the OGTT results of a diabetic patient?
fasting levels: >7.0mmol/L
at 2 hours: over 11mmol/L
What are the levels of HbA1c in a normal patient (mmol/mol and DCCT%)?
- <42mmol/mol
- <6.0%
What are the levels of HbA1c in a diabetic patient (mmol/mol and DCCT%)?
- > /= 48mmol/mol
- > /= 6.5%
What is the management of diabetes?
- lifestyle: nutrition, exercise, diet control to maintain BP
- medication
- surgery (for symptoms); pancreas transplant, kidney transplant, weight loss surgery
