week 2 Flashcards
what is the disease process of T2DM?
genetic+ environmental factors → insulin resistance → Compensatory beta-cell hyperplasia → failure to compensate (genetic predisposition)
what ethnicity is at a greater risk of T2DM?
east asian, indian
above what BMI for male and female is thee inc risk of T2DM?
24 Female; 25Male
in T2DM: insulin secretion
reduced
in T2DM: lipolysis
inc
in T2DM: glucose reabsorption in the kidney
inc
in T2DM: muscle glucose uptake
reduced
in T2DM: neurotransmitter
disturbance
in T2DM: hepatic glucose production
inc
in T2DM: incretin effect
reduced
in T2DM: glucagon
inc
how does the body adapt to insulin resistance? why does this fail?
inc Beta-cell mass.
genetic predisposition causes failure
why does weight reduction help T2DM
because its reduces insulin resistance and allows remaining Beta-cells to function with less.
how is theCVS risk address in T2DM?
statains and anti-hypertensives
management of type 2 DM
weight loss, exercise, metformin, statin, ACEi, diet/lifestyle, review appts.
how is metformin given initially
start 500mg and gradually increase due to GI side effects
what is the first line drug for type 2 DM?
metformin
how does metformin act
mechanism unclear.
reduces hepatic gluconeognesis and inc peripheral glucose uptake.
what are the adverse effect of metformin
GI and lactic acidosis (kidney, lung or liver disease beware)
what risk of three complications are reduced with good glucose control?
retinopathy, neuropathy, nephropathy.
what is seen as a good HbA1c
below 53
what is seen as a great/aggressive HbA1c
below 48
what are some second line drugs for type 2 DM?
SGLT2, glitazone, GLP-1R, SU, basal insulin, Gliptin (DPP-4 inhibitor)
what do incretins do?
stimulate decrease in blood glucose levels post-oral glucose (after eating).
((It is because of incretins and their amplifying effect that IV glucose has very shallow insulin spike compared to oral glucose))
what does obesity increase risk of?
T2DM
CVS: high BP, CAD, CHF, PE, Stroke
Cancer (many types)
OA, chronic back pain
Asthma, sleep apnoea, GB disease
what is the greatest contester to obesity - TV/cars or diet?
TV and cars
how does adipose tissue increase CVS risk?
adipose tissue is not inert, it has some similar properties to macrophages - key inflammatory cytokines found in adipose tissue can lead to atherosclerosis.
what is the function of leptin?
to tell body it has enough fat (energy stored as fat)
what happens if leptin deficient/lacking leptin receptors
inc appetite and weight gain
how is obesity treated?
diet, exersise, drugs, surgery
what drug can be used (as adjunct to dieting) to treat obesity?
Orlistat
how does Orlistat work?
inhibits lipase therefore blocking absorption of dietary fat in the gut
what are there procedures undergone in bariatric surgery?
gastic band, bypass or sleeve gastrectomy (long-term outcomes)
what is the best diet for weight loss?
low fat/low carbohydrate diets
success of diet depends on how committed patient is
why is it difficult to lose weight (after a little weight loss)?
because adaptive thermogenesis occurs
why does adaptive thermogenesis occur?
weight loss causes reduction in Resting Metabolic Rate(RMR) too but RMR falls MORE than expected making the next stage of weight loss more difficult
fat mass and non-fat mass make what
full body mass
what must occur in patient trying to lose weight
hypocalorific diet (intake must be less than usage) - the lower the RMR the harder to lose weight as the harder it is to keep intake under RMR
Name two advantages people with high metabolisms have
harder to gain weight
easier to lose weight (as RMR is higher easier to reach hypo calorific diet)
what are the risk factors for type2DM
obesity, age, genetics (ethrinicy, FHx), deprivation
what risk score is used to work out risk of type 2 DM in 10 years?
FINDRISC
what is important to consider/recommend in diet for diabetic (8 things)
Regular meals
Starchy CHO at each meal
Eat more fruit and veg
Cut down on fat, esp. saturated
Limit sugar / sugary foods
Reduce salt intake
Limit alcohol
Avoid diabetic foods
what is important in diabetes?: type 2 DM diet and aims
weight loss, smaller meals and snacks, physical activity, monitoring blood glucose and meds (if on insulin).
sustained weight loss/heatlhy weight alone can treat diabetes type 2
what is important in diabetes?: type 1 DM diet and aims
balancing insulin to CHO intake(carb counting), timing taking insulin, regular blood glucose monitoring.
what guide is used for macronutrient intake in diabetes
eatwell plate (similar to general population)
how to advise about sugars and sweeteners in diabetes.
no evidence that sugar has any greater impact than regular Carbohydrates - monitor OVERALL intake
what should be reduced by SIGN in non-pharamcological management of diabetes type 2
reduced energy dense foods (fat), fast foods, Alcohol and sedentary behaviour.
diet prescription by SIGN in non-pharamcological management of diabetes type 2
-600kcal deficit (tailored)
what is encouraged by SIGN in non-pharamcological management of diabetes type 2
Low energy density food and drinks
Mod to vig activity:
- Regular, tailored, provide support - If diabetic with complications - medical review
Self-weighing (caution - people have unreal expectations 5-10% loss is good but people aim for more than that)
stress and illness can impact on gylcameic control . T/F
true
exercise can cause what in diabetic (type 1). what needs done
hypoglycaemia, adjust dosage
alcohol and diabetes problems [2] and pros [1]
hidden calories.
hypo can occur (esp if no food 12-16 hours post-drinking) - esp if using insulin or SU’s
moderate-alcohol drinking may lower risk of diabetes
what is the Glycaemic index (GI)?
measure of impact food has on blood glucose rise. [insufficient evidence to recommend]
what does diet do in type 1 and 2? (prevention or management)
1- management
2 prevention and management.
what re the chronic complications of DM?
Macrovascular:
IHD
Stroke
Microvascular:
Neuropathy
Nephropathy
Retinopathy
Cognitive dysfunction/ Dementia
Erectile Dysfunction
Psychiatric
what is diabetes the leading cause of? (3 things)
blindness, dialysis, amputation
what causes microvascular pathology?
hyperglycaemia [and hyperlipidaemia]
what do hyperglycaemia [and hyperlipidaemia] cause that subsequently leads to microvascular complications
AGE-RAGE, hypoxia, oxidative stress, inflammation, mitochondrial dysfunction
what are microvascular complications associated with DM
retinopathy, nephropathy, neuropathy
what are the 4 types of neuropathy that can occur (due to DM)
peripheral, autonomic, proximal, focal neuropathy
what is peripheral neuropathy?
pain/ loss of feeling in feet, hands
what is autonomic neuropathy
changes in bowel (gastroparesis), bladder function, sexual response, sweating, heart rate, blood pressure
what is proximal neuropathy
pain in the thighs, hips or buttocks leading to weakness in the legs (Amyotrophy)
what is focal neuropathy
sudden weakness in one nerve or a group of nerves causing muscle weakness or pain e.g. carpal tunnel, ulnar mono neuropathy, foot drop, bells palsy, cranial nerve palsy
what are the risk factors for developing neuropathy due to DM?
Increased length of diabetes
Poor glycaemic control
Type 1 diabetes > Type 2
High Cholesterol/ Lipids
Smoking
Alcohol
Inherited Traits (genes)
Mechanical Injury
what are the symptoms of peripheral neuropathy?
Distal symmetric or sensorimotor neuropathy
Numbness/insensitivity;Tingling/ burning; Sharp pains or cramps; Sensitivity to touch; Loss of balance and coordination
what are complications of peripheral neuropathy?
charcot foot, painless trauma (object, fracture), foot ulcer (not felt due to bad footwear)
treatment options for painful neuropathy
ATYPICAL ANALGESICS; amitriptyline (off-label), duloxetine, gabapentin, or pregabalin; combinations not recommended. Titrate up as needed.
treatment options for painful neuropathy if localised neuropathic pain?
topical Capsaicin Cream
what is Charcot Foot?
reduced sensation and reduced proprioception with trauma/damage to foot causing loss of joint position/ osteoarthropathy
focal neuropathy PC/signs
sudden, affects specific nerves,
EG: Inability to focus eye Double vision Aching behind eye Bell’s palsy Pain in thigh/ chest/ lower back/ pelvis Pain on outside of foot
autonomic neuropathy affects what nerves?
affects nerves regulating HR + BP, as well as gastric motility, resp function, urination, sexual function and vision
what is AGE-RAGE
advanced glycation end products are proteins or lipids that become glycated as a result of exposure to sugars.
(factor in worsening of many degenerative diseases esp DM)
what problems in the digestive system can autonomic neuropathy cause?
gastric slowing/frequency (constipation and diarrhoea possible)
gastroparesis - slow stomach emptying causing persistent nausea, vomiting, bloatedness, los of appetite
oesophagus nerve damage causing dysphagia and wight loss
(all make BG levels hards to control)
how to treat gastroparesis causes by DM (autonomic neuropathy)
improve glycemic control
dietary (smaller portions with fibre - liquid meals if severe)
promotility durgs (metoclopramide) and anti-nausea meds (prochlorperazine). abdo pain (NSAID’s or tricyclic antidepressants).
botulinum toxin (into sphincter )
gastric pacemaker (severe)
how can sweat be affects in autonomic neuropathy
[nerves controlling sweating damaged so cannot regulate body temperature well] profuse nights sweats or while eating (gustatory sweating)
treatment for profuse nights sweats or gustatory sweating
Topical glycopyrrolate, clonidine, botulinum toxin
what can occur CVS-wise in autonomic neuropathy?
BP may drop sharply after sitting/standing (light headed/fainting)
HR may stay high instead of rising/falling to normal activities
investigations/diagnostic tools for neuropathy
nerve conduction studeis/EMG
HR variability
US
Gastric emptying studies
what is diabetic nephropathy?
A progressive kidney disease caused by damage to the capillaries in the kidneys’ glomeruli.
what is Diabetic Nephropathy characterised by?
nephrotic syndrome and diffuse scarring of the glomeruli
Microvascular changes- angiopathy of capillaries
what is Diabetic Nephropathy also known as
Kimmelsteil- Wilson Syndrome or Nodular Glomerulosclerosis
what are the Consequences
of Diabetic Nephropathy?
develop hypertension
relentless decline in renal function
accelerated vascular disease
how is Diabetic Nephropathy diagnosed?
micro/marcoalbuminuria
elevated creatine (severe)
what is used for Diabetic Nephropathy screening
urinary albumin creatinine ratio (ACR)
risk factors for neuropathy progression
Hypertension Cholesterol Smoking Glycaemic control Albuminuria
what needs done if patient has microalbuminuria?
monitor creatine level, monitor fasting lipid profile
screen for retinopathy/PVD/high BP/IHD.
discourage smoking
investigate other range causes
treatment for diabetic nephropathy
BP (agressive management - 130/70)
good glycemic control (HbA1c around 53 mmol/mol)
Patients with microalbuminuria or proteinuria should be commenced on an ACEi/ARB
what is the commonest cause of kidney failure/dialysis?
DM
common diabetic eye problems
Diabetic Retinopathy
Cataract
Glaucoma
Acute hyperglycaemia- visual blurring (reversible)
what is a cataract
clouding of lens (deveops earlier in diabetics)
what is glaucoma
increase in fluid pressure in the eye leading to optic nerve damage. [2 x more common in diabetes]
what are the stages of retinopathy?
Mild non-proliferative (Background)
Moderate non-proliferative
Severe non-proliferative
Proliferative
macula/maculopathy is important why?
macula is the centre of the retina [responsible for what we see straight in front of us/ at the centre of our field of vision.]
The macula is very important as it gives us the vision needed for detailed activities such as reading and writing, and the ability to appreciate colour (cones)
terminology in diabetic retinopathy: haemorrages, cotton wool spots, hard exudates, IRMA?
Haemorrages: Dot/ Blot/ Flame
Cotton Wool Spots: Ischaemic Areas
Hard Exudates: Lipid break down products
IRMA: Intra-retinal microvascular abnormalities (abnormalities of blood vessels/ precursor to neovascularisation but blood vessels are patent (not leaking))
what is graded separately when it comes to Diabetic eye problems?
Retinopathy and Maculopathy are graded seperately
describe what would be seen on pre-proliferative retinopathy?
Haemorrages and Microaneurysms only
describe what would be seen on mild background retinopathy?
Micro aneurysms, hard exudates, haemorrages
describe what would be seen on Severe Non-proliferative retinopathy?
IRMA, venous beading, haemorrages
describe what would be seen on Severe Proliferative retinopathy?
New Vessel Formation
what does bleeding at the back of the eye due to DM cause? [Vitreous haemorrhage]
Sudden change in vision
Floaters
what can occur in severe proferative diabetic retinopathy?
Pre-retinal Fibrosis +/- traction retinal detachment;
Vitreous haemorrhage
other complications include secondary glaucoma and retinal detachment
how is macula degeneration assessed?
Optical Coherence Tomography (OCT)
treatment for diabetic retinopathy?
(prevention= good BG control, statins, anti-hypertensives + annual screening, )
laser, vitrectomy, anti-VEGF injections
what complication can occur due to vascular and neuropathy in DM?
ED (erectile dysfuction) - 50% of diabetic men
what are risk factors for ED?
DM, CRF, hepatic failure, MS, depression, other(vascular disease, low HDL, high cholesterol, hormonal deficiency)
causes of ED
DM [vascular and neuropathy contributions]
spinal cord injuries, pelvic/urogenital surgery
alcohol, substance abuse, smoking,
current medications
drugs that can cause ED?
anti-hypertensives (All capable - Common: thiazides and BB - Uncommon: CCB’s, alpha-adrenergic blockers, and ACEi)
CNS drugs (Antidepressants, tricyclics, SSRIs
Tranquilizers
Sedatives
Analgesics)
what should all patients with diabetes should have at least annual screening of?
eyes, feet and kidneys [ACR/ U and Es]
-remember to think about ED
what may early detection prevent and reduce rates of?
prevent progression and reduce rates of blindness, amputation, foot ulcer and kidney failure (dialysis)
if what three things are controlled, then the risk of complications can be reduced substantially. what are the three factors
BG
BP
Blood lipid
(good control of all three lower complication risk)
name a buguanide
metfromin
give three examples of sulphonureas
Glicazide
Glibenclamide
Glimeparide
name a Thiazolidinedione
Pioglitazone
Rosiglitazone - withdrawn
(good )effects of metformin
Hyperglycaemia management:
Hypoglycaemia: (very rare when used as mono therapy)
Often reduces weight
Prevents microvascular/macrvascular complications:
(reduces trigylcerides + LDL + BP, safe in pregncacy, helps NAFLD, PCOS)
adverse effect of metformin
Common: GI :
Anorexia, nausea, vomiting, diarrhoea, abdo pain, [metal] taste disturbance
GI side effects in up to 25%; only 5% cannot tolerate the drug
Interference with vitamin B12 and folic acid absorption (anaemia is rare)
Lactic acidosis
rare unless renal/lung/heart disease
(Liver failure + rash very rare)
practical issues: metformin (how to start, when to stop, when to be cautious)
start low go slow for GI side effects,
caution in Cardio/resp/Renal patients.
half dose if eGFR 30-45 and stop is < 30
discontinue if advanced cirrhosis/liver failure
what is the first line agent for T2DM?
metformin
what are examples of 1 and 2 generation Sulphonylureas (SU)?
1st generation (rarely used any more):
Chlorpropramide
Tolbutamide
2nd generation (shorter acting):
Glicazide
Glibenclamide/glyburide
Glimepiride
what are the effects of SUs?
manage hyperglycaemia (potently), prevent microvascular complications
SU adverse effects
Hypoglycaemia - (Particular care in elderly/frail, alcohol excess, liver disease)
Weight gain
GI upset, headache
Rarely hypersensitivity, blood dyscrasias and liver dysfunction
Avoid in severe renal or hepatic failure
when are SU used?
second line after metformin
those intolerant to metformin
acute circumstances for gylcaemic control (takes 48hrs to work whereas metformin takes a few weeks )
TZD’s/Thiazolidinediones act in what way?
PPARγ agonists
TZD effects (good)
Hyperglycaemia management:
Hypoglycaemia not common
Improvement in microalbuminuria (no vascualr improvement however)
TZD effects [bad]
Hypoglycaemia (if used with SU)
Weight Effect: inevitable
due to increase in subcutaneous (but not visceral) fat and fluid retention
Heart Failure
bone density affects (# rate)
who are TZD’s not given to? why?
over 65’s (# risk)
HF patients (Fluid retention results in near doubling of risk of admission with heart failure (risk still low in non-elderly without pre-existing HF))
what type of drugs act on the incretin pathway?
GLP-1R agonists
DPP-4 inhibitors
what is the incretin effect
less insulin produced off IV rather than oral glucose (due to incretins from gut being transported in blood to pancreas)
why is hypoglycemia more common in SU?
because B cells continually produce insulin.
what two incretins (intestinal secretion of insulin) molecules are there and what cells are they from?
GIP ;Kcells
GLP-1; L cell
example(s) of a GLP -1R agonist
Exenatide
[Exendin, Liraglutide, Lixisenatide]
benefits of GLP-1R agonist
Promote insulin secretion from pancreas without hypoglycaemia
Suppress glucagon (which is increased in T2DM)
Decrease gastric emptying – early satiety
Act on hypothalamus – reduce appetite – resulting weight loss (~3kg
[reduced CVS outcomes, death and improves renal disease]
disadvantages of GLP-1R agonist
Nausea – usually resolves in most by 6-8 weeks
Injectable
pancreatits?
DPP-4 inhibitors example of?
Vildagliptin, Sitagliptin, Saxagliptin, Linagliptin
why are DPP-4i’s less potent than GLP-1 mimetics?
as can only work on what’s there and GLP-1 levels are low in T2DM
pro’s of DPP-4i’s
Promote insulin secretion from pancreas without hypoglycaemia
Suppress glucagon (which is increased in T2DM)
Weight neutral
cons of DPP-4i’s
Very limited side effects
Not that potent
No weight loss
Pancreatitis?
examples of SGLT2 inhibitor (3)
CANAGLIFLOZIN
EMPAGLIFLOZIN
DAPAGLIFLOZIN
what do SGLT2 inhibitors do/how they work?
decrease uptake of sugar in kindness glomerulus by about one quarter (pee out sugar!)
pro’s of SGLT2i’s
weight loss,
blood sugar control,
reduced CVS events, death and hospitalisation for HF
benefical for most renal outcomes
cons of SGLT2 i’s
sugar in urine causes PC of T2DM symptoms (INC THRUSH AND INC URINE INFECTIONS)
doesn’t work well if kidney damages (eGFR <60 not used)
which T2DM drugs give CVS benefit?
Empagliflozin (and probably all SGLT2i), Liraglutide
Semaglutide, Pioglitazone.
slightly metformin and exenatide
which T2DM drugs are neutral in CVS benefit?
Lixisenatide, DPP4i, SU