Diabetes Flashcards
Look at diagrams on slides
Look at diagrams on slides
Uses of blood glucose
Muscle storage for later use (glycogen)
Energy source for muscle and other tissues
Storage as fat (triglycerides)
Liver storage for later use (glycogen)
Energy for CNS and brain (60-70%)
Excretion in urine with high blood sugar (~>160mg/dL)
Regulation of blood glucose
Maintenance of blood glucose levels essential
Too high: release of water from tissues due to osmotic pressure: dehydration, death
Too low: lack of fuel to produce ATP
-brain depends on glucose as fuel (can’t use fats etc.) –> coma
-RBCs low on ATP; can’t provide oxygen to tissues –> death
Low blood sugar –>
alpha cells in pancreas respond
- release glucagon
- stimulates liver to break down glycogen and release glucose into blood
- normal blood glucose achieved
High blood sugar –>
Beta cells in pancreas respond
- release insulin
- stimulates muscles and fat cells to take glucose from blood
- normal blood glucose achieved
Diabetes origin
From latin - siphon
From Greek - a passing through (reference to excessive urination)
Recognised for 2000 years
Originally diagnosed by sweet taste of urine
Known as Pissing Evil in 17th century
Blood glucose levels fasting
Normal fasting conditions: 3-5 mmol/l
Diabetic fasting conditions: 4-7 mmol/l
Blood glucose after a meal
Normal: less than 10 mmol/l 90 min post food
Diabetes: >20 mmol/l
Diabetes mellitus
Metabolic disorder of carbohydrate metabolism
Characteristic: hyperglycaemia (> blood glucose)
High morbidity and mortality
Macrovascular complications
Stroke Heart disease -atherosclerosis -endothelial dysfunction -hypertension -procoagulant state -antifibrinolitic state -vascular inflammation Peripheral vascular disease
Microvascular complications
Retinopathy -macular edema -capillary nonperfusion -angiogenesis -haemorrhage -glaucoma Nephropathy -damaged glomeruli -hyperfiltration -renal damage Peripheral neuropathy -nerve damage -ulceration -necrosis Foot problems
Symptoms of diabetes
Blurry vision > thirst and need to urinate Feeling tired or ill Recurring skin, gum, bladder infections Dry, itchy skin Unexpected weight loss Slow healing cuts and bruises Loss of feeling or tingling feeling in feet
Types of diabetes
Type I (insulin dependent)
Type II
Gestational diabetes
Impaired glucose tolerance (IGT) and impaired fasting glycaemia (IFG)
Type I diabetes
Chronic (generally) childhood disease
Affects 18-20 per 100,000 children in UK
Sometimes associated with thyroid disease
Genetic susceptibility shown
Linked to viral infection (e.g. congenital rubella syndrome)
Type I diabetes science behind
Lack of insulin production Thought to be autoimmune mediated disorder -affects islets of Langerhans -beta cells killed by antibodies Therefore, lack of insulin production Most cases <40
Type 2 diabetes
Non-insulin dependent/ adult-onset diabetes
Genetic disposition + environment
Type 2 diabetes causes
Genetic disposition:
-multiple genetic susceptibility –> primary beta-cells defect –> damaged/ inadequate insulin secretion
-multiple genetic susceptibility –> periphery insulin resistance –> inadequate uptake
Environment: obesity
—–> hyperglycaemia + free fatty acids –> type 2 diabetes
Insulin resistance
Lack of insulin results in low glucose in cells i.e. cells do not take up glucose
Insulin resistance –>
- ->liver: produces glucose from stored glycogen –> slow to replenish glycogen –> glucose not taken by cells and blood glucose increases
- ->skeletal muscle: < glycogen storage and use of glucose –> glucose not taken by cells and blood glucose increases
- -> fatty tissue: fat broken down and use as energy source –> > fatty acids as some insulin in present, normal fatty acid metabolism occurs and no ketones are produced
Type 2 diabetes main symptoms
- Polyuria: frequent urination due to osmotic diuresis
- Polydisia: > thirst and > fluid intake due to polyuria
- Polyphagia: > appetite
Type 2 diabetes other symptoms
Dry mouth, itchiness, > incidence of thrush, cramps, skin infections
Gestational diabetes
2-5% of all pregnancies
Onset in late 2nd trimester (20-28 weeks)
Gestational diabetes predisposing factors
Age (>35 although can occur in younger mums)
Ethnic group
-6x more common in South Asian descent
-3x more common in African-Caribbean people
Obesity
Gestational diabetes symptoms
No obvious external symptoms On occasions, classic diabetes symptoms are observed -excessive thirst -frequent urination -increased appetite
Gestational diabetes causes
Hormonal changes –> cells less responsive to insulin
Increased resistance to insulin
> blood glucose
Long-term effect: larger babies, mum at risk of type 2 diabetes
Glucose testing
Fasting plasma glucose (FPG) Oral glucose tolerance test (OGTT) Random plasma glucose test Glycated haemoglobin A1c (HbA1C) Fructosamine test
Fasting plasma glucose (FPG)
Measures blood glucose when person has not eaten for at least 8h (detect diabetes and pre-diabetes)
Oral glucose tolerance test (OGTT)
Measures glucose after individual has fasted for at least 8h and 2h after consuming glucose containing drink (detect diabetes and pre-diabetes)
Random plasma glucose test
Casual plasma glucose test i.e. measures glucose irrespective of whether person has eaten or not (diagnose diabetic only)
Glycated Haemoglobin A1c (HbA1C)
Red cells life spain is ~8-12 weeks
Hb1Ac given indication of average glucose level for 8-12 weeks
Normal: 2.5-5.5%
Diabetes: ~6.5%
One of best ways to check that diabetes is under control
Fructosamine (Glycated serum protein, glycated albumin) test
Formed from serum proteins such as albumin -reaction between fructose and amine Used in cases of -blood loss -haemolytic anaemia -sickle cell anaemia Gives average results for last 2-3 weeks Tends to be basis of over-the-counter tests
Hyperglycaemia: other factors
Steroids
Antipsychotic
Diuretics
Antihypertensive
Hypoglycaemia: other factors
Alcohol
Hormone deficiencies
Prolonged starvation
Management of diabetes aim
To lower blood glucose levels
Monitor blood glucose regularly
Regular meal times
Important to follow up care
Management of diabetes type 1
Insulin (essential)
Exercise
Diet (low in fat, cholesterol and simple sugar)
Management of diabetes type 2
Weight reduction
Diet
Exercise
If above not successful then oral hypoglycaemic medications and then insulin
Management of diabetes: sugar
Avoid adding sugar to food
Avoid foods sweetened with sugar or honey
Management of diabetes: cholesterol and fat
> carbohydrates before sustained exercise
Limit intake of saturated and hydrogenated fats and cholestertol
Diabetes treatments
Oral hypoglycaemic agents:
- Biguanides (Metformin) - type 2 diabetes and type 1 with insulin therapy
- Sulphonylureas (Tolbutamide, gliclazide, glimepiride)
Biguanides (Metformin)
Inhibits glucose production by liver (gluconeogenesis)
Useful in pxs who are obese
Sulphonylureas
> amount of insulin made in pancreas (required functional islets of Langerhans)
Long lasting effect
-problem: hypoglycaemia in elderly pxs or those with kidney problems
Unwanted effects of Sulphonylureas
Appetite stimulants (weight gain) Hypoglycaemia GI upsets (3% of pxs) Potentially teratogenic (do not use in pregnancy or planning one)
Unwanted effects of Biguanides (Metformin)
- GI disturbance
- lactic acidosis (contrindicated for those with renal, severe pulmonary or cardiac conditions)
Drugs that augment hypoglycaemic effects of sulfonylureas
NSAIDs
Alcohol
Antibacterial (Sulphonamides, trimethoprim, chloramphenicol)
Antifungal (Miconazole, fluconazole)
Drugs that decrease the actions of sulfonylureas
Diuretics
Corticosteroids
Diabetes and oral health
Oral disease has been referred to as 6th ‘opathy’ of diabetes
Dental diseases due to diabetes: gum diseases very common
-red and swollen gums
-> bleeding while brushing
-> plaque
Results in periodontitis and gingivitis
-gum disease followed by tooth decay
-inflamed and sore tissues, ulcers
Lack of saliva (xerostomia)
Dental hygiene, diabetes and heart problems
> bleeding time –> longer to heal
Lack of saliva (xerostomia)
< salivary flow –> bacteria and other residues not washed
< antimicrobial effect of saliva
> oral infections (e.g. thrush very common in diabetics)
Dental hygiene, diabetes and heart problems
Bacteria can enter blood stream - endocardititis
Cholesterol build up in blood stream - atherosclerosis
Diabetes and smoking
Diabetic smokers have higher risk of dental problems e.g. periodontitis
Smoking impairs blood flow and affects healing after dental proceduse
Risk increases with smokers > 45
> risks of morbidity and premature deaths (macrovascular complication)
Care of diabetic dental pxs: major surgery procedures
Diet control
Reduce stress
Insulin & blood sugar control
Antibiotic requirements
Care of diabetic dental pxs: invasiev procedures
Morning appointments Reduce stress Current medications; insulin & blood glucose levels Antibiotic requirements Treatment breaks
Care of diabetic dental pxs: non-invasive procedures
Morning appointments Medications being taken Analgesic requirements Need for treatment breaks e.g. bathroom & snacks Stress importance of regular visits
Pre-diabetes
Precursor to diabetes
Tend to lead to full diabetes developing
Frequently associated with poor diet/ obesity/ lifestyle issues
Abnormally high blood glucose - perhaps not high enough or without symptoms for full diabetes
Pre-diabetes forms
Impaired fasting glycaemia
Impaired glucose tolerance
Impaired fasting glycaemia
Elevated high blood glucose, not high enough to be diabetic
50% risk of progressing to diabetes
Lifestyle changes can reduce risk of progressing
Impaired glucose tolerance
After eating, between normal blood glucose and diabetic blood glucose levels
Associated with > risk of cardiovascular problems
Diet, lifestyle changes reduce risk of progressing
