What is Diabetes Mellitus? (including Epidemiology of Diabetes) Flashcards
what is the definition of diabetes mellitus
group of metabolic diseases of multiple aetiologies characterised by hyperglycaemia together with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion, insulin action or both
what is polydipsia
excessive thirst
what is polyuria
noun: polyuria
production of abnormally large volumes of dilute urine
what are symptoms of hyperglycaemia
polydipsia polyuria blurred vision weight loss infections tiredness
what are long term complications of hyperglycaemia
microvascular e.g retinopathy, neuropathy,nephropathy
macrovascular e.g stroke, MI, PVD
what can be measured in order to diagnose diabetes
blood glucose
HbA1c
what is a HbA1c
a glycosylated haemoglobin molecule
what is the relationship between HbA1c and glucose in the blood
the more glucose in the blood the more HbA1c will be present in the blood
what is the diagnostic glucose level for fasting
> 7.0 mmol/l (or equal to)
what is the diagnostic glucose level at random
> 11.1 mmol/l (or equal to)
if glucose levels are >11.1mmol/l after an oral glucose tolerance test what does this indicate
diabetes
what does a HbA1c level of 48mmol/mol indicate
diabetes
what is gestational diabetes
high blood sugar that develops during pregnancy (usually disappears after birth)
what are cases where HbA1c cannot be used for diagnosis of diabetes
- children young people
- pregnancy
- short duration of symptoms
- patients who are acutely ill
- HIV
- pancreatic damage
what is the most common type of diabetes
type 2 (88%)
what is the only hormone that lowers blood glucose
insulin
what do alpha cells in the pancreas secrete
glucagon
what is hyperglycaemia
abnormally high blood glucose level
what is ketonaemia
presence of abnormally high ketone bodies in the blood
what are the symptoms of untreated type 1 diabetes
thirst tiredness polyuria/nocturia weight loss blurred vision abdominal pain
what may be found on investigation that would support the diagnosis of type 1 diabetes
ketone breath dehydration increased RR tachycardic hypotension low grade infections e.g thrush
what are the symptoms of undiagnosed type 2 diabetes
may have none thirst tiredness polyuria/nocturia sometimes weight loss blurred vision symptoms of complications e.g CVD
what signs may be found on examination that would support a diagnosis of type 2 diabetes
NOT KETOTIC
usually overweight (not always)
low grade infections
type 2 DM may have microvascular/macrovascular complications at Dx
what are risk factors for diabetes
overweight family history inactive lifestyle previous high bld Glu impaired Glu tolerance
what are particular risk factors for diabetes in woman
history of diabetes in pregnancy (gestational diabetes)
had a big baby (more that 4kg)
what ethnicities/age groups are more at risk of diabetes
> 30 yrs if Maori/Asian /Pacific island descent
> 40yrs if European
what is the cause of Maturity Onset Diabetes in the Young (MODY)
autosomal dominant single gene defect which results in impaired beta cell function
what is the function of Glucokinase
it is a gene that plays an important role in recognising how high blood glucose is in the body. It acts as the glucose sensor for the pancreas.
what is secondary diabetes
diabetes that occurs as a result of another medical condition
what can cause secondary diabetes
drug therapy-corticosteroids
pancreatic destruction
endocrine disorders e.g Cushing’s, Acromegaly, pituitary tumour
