Diabetes Flashcards
What is the definition of diabetes by WHO?
Diabetes is a chronic, metabolic disease characterized by elevated levels of blood glucose (or blood sugar), which leads over time to serious damage to the heart, blood vessels, eyes, kidneys, and nerves.
What is the most common type of diabetes?
Type 2
Explain how type 1 diabetes is an auto immune disorder?
Develop antibodies that attack the beta cells which causes insulitis and eventually results in complete destruction and inability to produce insulin.
4 Ts for children with type 1 diabetes?
Tired
Toilet (increased frequency)
Thirsty
Thinner
Describe classic type 1 diabetes presentation?
Pre-school and peri-puberty Small peak in late 30’s Usually lean Acute Onset severe symptoms severe weight loss ketonuria and/or metabolic acidosis no evidence of microvascular disease at diagnosis immediate and permanent requirement for insulin
Describe classic type 2 diabetes presentation?
middle-aged/elderly
usually obese
pre-diagnosis duration of probably 6-10 years
insidious onset over weeks to years
ketonuria minimal or absent
evidence of micro-vascular disease at diagnosis in 20 %
managed initially with diet + tablets
Describe 4 blood tests for diabetes
Fasting glucose
HbA1c
2hr glucose in OGTT
Random Glucose
What is the 2hr glucose in OGTT?
Oral glucose tolerance test, you measure fasting glucose then give sugary solution and see what there glucose is after 2hrs.
Describe HbA1c test and how it works?
It measures glaciated haemoglobin so gives an idea of your blood glucose for the last 2-3months.
What is the diagnostic criteria for diabetes?
HbA1c: 48 mm/mol or above Fasting glucose: 7mm/mol or above 2hr glucose in OGTT: 11.1mm/mol or above Random glucose: 11.1mm/mol or above One abnormal value for symptomatic individuals and two are needed for asymptomatic people. Glucose tolerance test usually only required for borderline cases or gestational diabetes.
Fasting is defined as no calorific intake for at least…
8 hrs
Testing for diabetes or prediabetes in asymptomatic adults should be considered in…
First-degree relative with diabetes
High-risk race/ethnicity (e.g., African American, Latino, Native American, Asian American, Pacific Islander)
History of CVD
Hypertension (≥140/90 mmHg or on therapy for hypertension)
HDL cholesterol level <35 mg/dL (0.90 mmol/L) and/or a triglyceride level >250 mg/dL (2.82 mmol/L)
Women with polycystic ovary syndrome
Physical inactivity
Other clinical conditions associated with insulin resistance (e.g., severe obesity, acanthosis nigricans)
What are normal blood results?
HbA1c: 41 mm/mol or below
Fasting glucose: 6mm/mol or below
2hr glucose in OGTT: 7.7mm/mol or below
Describe the 4 types of diabetes?
Type 1: auto immunity to beta cells no insulin
Type 2: increased resistance to insulin action
Type 3: Gestational diabetes (Any degree of glucose intolerance arising or diagnosed during pregnancy)
Type 4: Others causes e.g. pancreatic disease, endocrine disorders, drug induced, genetic related e.g. CF
Risk factors for type 2 diabetes?
Obesity
Genetic susceptibility
South East Asian have higher rates in slimmer adults
Family history
Associated with hypertension, hyperlipidaemia, hyperglycaemia and polycystic ovarian syndrome (so must check for these)
Describe presentation of type 2 diabetes?
May present asymptomatic from screening or be an incidental finding in hospital.
If symptoms: usually doesn’t present acutely, and often signs of microvascular complications already.
Symptoms: thirst, polyuria, thrush, weakness, fatigue, blurred vision, infections, complications e.g. neuropathy and retinopathy.
Type 2 diabetes is a diagnosis of _________
exclusion
Why does polyuria occur in diabetes?
Increased urination: Occurs due to excess sugar in the blood. Normally when kidneys create urine they reabsorb glucose but instead it goes into the urine as body attempts to lower glucose.
Why does polydipsia occur in diabetes?
Increased thirst: glucose in urine pulls water out with it
Why does thrush occur in diabetes?
High glucose is favourable conditions may also have irritated skin and a lower immune response
Why does fatigue occur in diabetes?
Blood sugar changing and also dehydration
Why does blurred vision occur in diabetes?
High blood sugar causes the lens in the eye to swell
Explain tests that can rule out other forms of diabetes and rule in type 2?
Test for type 1 antibodies in combination 95% sensitivity so if don’t have only 5% chance it’s type 1. GAD, IA-2 and ZnT8.
Measure C-peptide, this will only decrease after 3yrs (children), 5yrs (adults) in Type 1 so is useful for confirming type 1 as opposed to diagnosing type 2 (NOTE occasionally type 1 has persistent C-peptide)
Can measure C peptide in type 2s after fasting.
Describe overview of treatment for type 2?
Lifestyle changes in everyone then
Pharmacological agents and manage and screen for microvascular complications
Type 2 should treat to lower HbA1c to ______
Why?
53mmol/l
This reduces risks of complications but don’t try and get any lower as bad results from study
Explain the pharmacological treatment of type 2 diabetes?
Metformin- first line
Sulphonylureas- first line when metformin contraindicated or intolerant. Can also be add on treatment.
Thiazolidinediones, DPP4i, SGLT2i and GLP agonists also all add ons.
Insulin last resort.
SGLT2i given to those with established CV disease or sometimes GLP agonists
GLP given to those BMI over 30 with poor control as help lose weight.
When is metformin contraindicated?
Renal impairment
Contraindications for Thiazolidinediones? Adverse effects?
Many actually taken off market
Pioglitazone contraindicated in HF and increases risk of fractures as well as bladder cancer.
Describe BMI calculation and interpretation?
BMI= kg/m2
Normal= 18.5-24.9
Overweight= 25-29.9
Obese= 30 and above
Why can waist circumference give more information than BMI?
BMI doesn’t differentiate between fat or muscle whereas waist circumference measures visceral fat.
Describe normal and overweight waist circumferences?
- Male high WC= 94-102 and very high more than 102
* Women high WC= 80-88 and very high more than 88
What ethnicity risks from obesity start at lighter weights?
South asians
What are the physical activity guidelines?
150 mins of moderate activity a week or 75 mins of vigorous activity or combination
Plus strength 2 days a week
Minimise sedentary time
Older adults should do balance improving things
Define Monogenic Diabetes
Rare types of diabetes caused by a single gene mutation.
When should you consider monogenic diabetes?
In people presenting with early onset diabetes in association with an affected parent and early onset diabetes in approx. 50% of relatives.
MODY is autosomal ________
dominant
Explain two genetic defects that can cause MODY?
Glucokinase defect
Defects in HNF transcription factors particularly HNF-1alpha
Describe how glucokinase defect cause MODY and what the treatment is
The gene helps the body recognise how high the blood glucose levels are so without this blood glucose is slightly higher than normal.
Will have a higher than normal glucose from birth
Complications are rare and there is no evidence that treatment is beneficial, only relevant to know about in pregnancy.
Compare onset of glucokinase MODY vs HNF-1alpha MODY
Glucokinase will have hyperglycaemia from birth as just have different set homeostatic point whereas in HNF-1alpha the diabetes will develop gradually with onset in adolescence early 20s
Complications occur in glucokinase or HNF-1alpha MODY?
HNF-1alpha complications are much more common
Don’t get complications in glucokinase
Describe how HNF-1alpha mutation causes MODY and what the treatment is
Transcription factor mutation that results in less insulin being produced by the pancreas
Diabetes develops in adolescence/ early 20s complications are frequent
This should be treated with SUs (gliclazide) as this allows insulin to be secreted so is important to differentiate from Type 2
Treatment of HNF-1 alpha MODY vs glucokinase?
Glucokinase doesn’t need treatment
HNF-1alpha give sulfonylureas (gliclazide)
Define neonatal diabetes?
Diabetes that requires insulin treatment in the 1st 3 month
Unlikely to be type 1 diabetes if child is under…
1
Describe transient and permanent neonatal diabetes?
Transient neonatal diabetes is usually diagnosed within the first week and resolves by week 12. Can get permanent neonatal diabetes which is usually diagnosed 0-6 weeks and needs lifelong treatment.
What are many forms of neonatal diabetes due to?
Mutations in KATP channel in sensing ATP so can be treated with SUs which will close the channel if ATP cannot.
Treatment of neonatal diabetes?
If mutation in KATP channel in sensing ATP can give SUs (glibenclamide) as this will help close the channel so insulin can be secreted
Some may need insulin treatment.
In primary care what are high risk groups that should be recalled annually to screen for diabetes? What test is done?
Fasting Glucose plasma measurement
- Impaired glucose tolerance (pre-diabetes)
- Impaired fasting glycaemia (pre-diabetes)
- Past history of gestational diabetes
What is gestational diabetes?
Gestational diabetes is high blood sugar (glucose) that develops during pregnancy and usually disappears after giving birth. It happens when your body cannot produce enough insulin to meet your extra needs in pregnancy.
Describe when diabetes needs referred to secondary care?
- Definite or likely type 1 diabetes needs a URGENT referral to secondary care
- Type 2 diabetes is often managed in primary care
- All children need referred or those with low or low normal BMI but NOT urgent
- Patients pregnant or planning pregnancy need referral
- Pre existing renal impairment needs referred
- Other clinical concerns refer
- Consider referral if patient if patient under 40 at diagnosis particularly if strong family history
Blood glucose levels will usually ______ in response to stress or illness
rise
High creatinine can indicate….
kidney damage
What are the potential macrovascular complications of diabetes?
Stroke, MI, peripheral vascular disease, atherosclerosis risk all increased in diabetics but these conditions are not specific to diabetics.
What are the potential microvascular complications of diabetes more specific to diabetes?
Eye disease- retinopathy, cataracts, maculopathy, blurring, glaucoma
Nephropathy
Neuropathy- peripheral, proximal, autonomic
What are the eye complications with diabetes?
Retinopathy (most common) Maculopathy and macular oedema Earlier development of cataracts Glaucoma Visual Blurriness caused by acute hyperglycaemia
How can you reduce the risk of eye complications in those with diabetes?
Annual screening for all low risk diabetics helps identify those who need referred to the eye clinic
What happens in diabetic kidney disease?
Progressive kidney disease caused by damage to the capillaries in the kidney’s glomeruli