Intro To Diabetes Flashcards
What is diabetes
Diabetes is when blood glucose is too high and over years leads to damage of the small and large blood vessels causing premature death from CV disease
Why is diabetes a major health concern
10% of the NHS budget 2014
1 in 4 develops kidney disease and is the single most common cause of ESRD in UK
Leading cause of blindness of working age
Most common cause of non traumatic lower limb amputation
15% life time risk of amputation
70% deaths due to cardiovascular disease (CAD and stroke)
Life expectancy is reduced on average by 5 to 15 years in people with T1DM and 5 to 10 years with
T2DM
Pathophysiology of diabetes
Pathophysiology of Diabetes
When you eat, your body breaks food down into glucose. Glucose is a type of sugar that is your body ’s main source of energy
Pathophysiology of Diabetes - As blood glucose rises, the body sends a signal to the pancreas, which releases insulin
Acting as a key, insulin binds to a place on the cell wall (an insulin receptor), unlocking the cell so glucose can pass into it. There, most of the glucose is used for energy right away
So why does blood glucose rise?
Simply put….
Inability to produce insulin due to beta cell failure and / or
Insulin production adequate but insulin resistance prevents insulin working effectively and invariably linked to obesity
Knowing that these are the 2 principle mechanisms helps understand how diabetes is treated
T1 and T2 DM
Type 1 diabetes - The pancreas does not produce enough insulin (absolute insulin deficiency) due to an immune based destruction of beta cells
Type 2 diabetes - Your pancreas may not produce enough insulin (relative insulin deficiency)
Or your cells do not use insulin properly. The insulin cannot fully “ unlock” the cells to allow glucose to enter (insulin resistance).
Presentation and diagnosis of DM
Typical symptoms of hyperglycaemia
Polyuria, polydipsia, blurring of vision, urogenital infections - thrush
Symptoms of inadequate energy utilisation
Tiredness, weakness, lethargy, weight loss
The severity of these symptoms will depend upon the rate of rise of blood glucose as well as the absolute levels of glucose achieved
Diagnosis of diabetes
You need laboratory confirmation on
Fasting glucose
Oral Glucose tolerance test
HbA1c
You need symptoms and 1 abnormal test or 2 if asymptomatic
All acceptable but need to recognise that patients may be positive on 1 or 2 tests but not all three
Type 1 diabetes
Absolute insulin deficiency secondary to autoimmune destruction of
Importance of ketones
Ketone production is suppressed by insulin
Except in the presence of starvation - there will be a Trace of ketones in healthy starved people
Serum or urine
In the absence of insulin, ketone production is activated
Presence of ketones is indication for immediate insulin therapy
Should not wait until tomorrow
Ketoacidosis definition - Hyperglycaemia, Ketonaemia (abnormally high ketone bodies in the blood), Acidosis
Absolute or relative deficiency of insulin
Enhanced lipolysis leads to uncontrolled ketosis
Large quantities of ketone bodies formed including 3- beta-hydroxybutyrate, acetoacetic acid and acetone (get pear drop smell on breath)
Type 2 Diabetes
Affects 4.5 million people in UK
90% of type 2 DM are overweight or obese
Prevalence increasing dramatically
Many asymptomatic and diagnosis made at routine health checks
Most are over 40 years of age
Often managed by diet and tablets
However, increasing seen in younger people and children
Type 2 diabetes: What causes insulin resistance to develop?
Obesity – in particular central obesity
Accounts for 85% of the risk for developing diabetes
Muscle and liver fat deposition
Elevated circulating Free fatty acids
Can also be contributed by Physical inactivity And genetic influences
Hunter gather to fast food in a generation
liver fat content decreases with low calorie dieting
Within 7 days fasting blood glucose normalises in Type 2 diabetes
BEFORE any weight loss - There is a massive fall in liver fat content and return of NORMAL insulin sensitivity
This change is in step with decreasing pancreatic fat content normalising ß cell function
Over 8 weeks first phase insulin release and maximal rates of insulin release return to NORMAL
Type 2 diabetes can be considered as a potential reversible metabolic disorder precipitated CHRONIC intraorgan fat
Signs, treatment and complications of T2 DM
Symptoms
Very variable as slower rise in blood glucose
May have polyuria, polydipsia, weight loss
Can be difficult to elicit from patient • No urinary ketones
May be asymptomatic
Diagnosis made by routine screen
Patient Usually, though not universally, older Most are over 40 years of age Increasing seen in younger people and children 90% are overweight or obese
How do we treat Type 2 diabetes?
Lifestyle
Non-insulin therapies
Biguanides, sulphonylureas, thiazolidinediones, GLP1 analogues. DPP4 inhibitors,
Metabolic syndrome
Metabolic syndrome is a cluster of the most dangerous risk factors associated with cardiovascular disease: - diabetes and raised fasting plasma glucose, abdominal obesity, high cholesterol and BP
Together they confer a marked increase in cardiovascular risk
For a person to have the metabolic syndrome:
Waist measurement > 94cm for men and > 80 cm for women
Plus any 2 of the following:
Raised triglyceride > 1.7mmol/l or treatment
Reduced HDL cholesterol <1.0 for men and 1.2mmol/l for women
Raised blood pressure > 135/85 or treatment
Or raised fasting blood glucose > 5.6mmol/l or treated diabetes
What causes the metabolic syndrome?
Insulin resistance and central obesity, genetics, physical inactivity, ageing
