micro and macrovascular compl of t2d Flashcards
3 types of microvascular complications
retinopathy, nephropathy, neuropathy
3 types of macrovascular disease
ischaemic heart disease, cerebrovascular disease, peripheral vascular disease
when does risk of microvascular disease increase exponentially? (what factor)
blood glucose/ hyperglycemia- target hba1c- below 53
what factor other than blood glucose do you need to check to avoid microvascular complications? (proportional relationship- linear)
blood pressure- HYPERTENSION
what are 2 blood-content related factors that are associated with microvascular complications
hyperlipidaemia (high cholesterol)- clogs arteries
hyperglycaemic memory- when for a period of time you had high-uncontrolled gluc levels and this can cause problmes later on (due to endothelial damage)
what are other factors that can increase risk of microvascular complications
duration of diabetes - when had for longer- since younger - think t1d usually- you need to monitor more
smoking - endothelial dysfunction
genetic factors - some people control glu less well and dont get compl and vise versa
when we say microvascular damage what part pf the vessel is actually being damaged?
endothelium
mechanism of microvascular damage (endothelium)
1) hyperlipidaemia and hyperglycaemia lead to
2) OXIDATIVE STRESS leads to
3) increased formation of mitochondrial superoxide free radicals (leads back to 2)
+
4) glycation of plasma porteins leaidng to advanced glycation poducts (AGEs)
5) activation of inflammatory pathways
6) damaged endothelium : a)leaky capillaries
b) ischaemia
what is the main cause of
visual loss in people with diabetes and blindness in people of working age?
diabetic retinopathy
how often do diabetics get screened for diabetic retinopathy and why?
annually because it initially is asymptomatic and we want to catch before it causes visual loss/ disturbance (irreversible)
what is another cause of visual disturbance in diabetes? what type fo disturbance?
blurry vision at start of diabetes due to thickening of lens in eye- part of osmotic sympotms- reversible and NOT THE SAME AS RETINOPATHY
What are the 2 normal features seen in a normal retina, where is each located and which is bright/ dark (in examination)
optic disc - side- bright
macula/ fovea - centre - dark (high resolution central colour vision)
what are the 4 pathologies in the eye?
background retinopathy
pre-proliferative retinopathy
proliferative retinopathy
maculopathy
which type of retinopathy is the least and which is most dangerous
least: background
most: proliferative
features in background retinopathy
1) dot (aneurisms) and blot haemorages
2) hard exudate - cheese colour from lipids
features in pre-proliferative retinopathy
“cotton wool” spots/ soft exudate - they are bright- represent retinal ischaemia (here we dont have the dots and blots- only these bright spots)
features of proliferative retinopathy
you see more branches on the retinal vessels/ more vessels (on disc or elsewhere in retina)
features of maculopathy
hard exudate but only around macula (Looks like background retinopathy but ONLY around macula as opposed to around the whole retina)
what does the management of all the eye pathologies involve before we move onto any kind of treatment?
Improve HbA1c, stop smoking, lipid lowering, good blood pressure control <130/80 mmHg
what is the management of background retinpathy?
continued annual surveillance
management of pre-proliferative retinopathy?
if left untreated will rpogress to proliferative so - early PANRETINAL photocoagulation
management for proliferative retinopathy
pnretinal photocoagulation
management for diabetic maculopathy
its oedema so: injection of anti-VEGF (vascular endothelial growth factor) straight into the eye
and grid photocoagulation
what is seen in the retina after pan retinal photocoagulation? what does this mean clinically?
black spots on the periphery of the retina- loss of some peripheral vision - its worth it bc if you leave it to proliferate it will lead to uncontrolled loss of vision
What stage of diabetic retinopathy can be observed rather than treated?
background retinopathy
3 reasons why diabetic nephropathy is important/ serious
associated with cardiovascular complications,
associated with END STAGE renal failure which requires haemoDIALYSIS
healthcare burden
what is an appropriate measurement for diabetic nephropathy surveillance?
Urine Albumin: creatinine ratio (UACR)
what is normal ACR and what are the 3 progression stages?
normal ZERO
microalbuminurea: >3 mg/mmol
proteinurea: >30mg/ mmol
nephrotic range: >3000mg/ 24hr
what do you do if a UACR comes back positive and why?
you need to repeat it to confirm because its ommon to have false positives due to UTI, fever
what are some innapropriate measurements for screening for diabetic nephropathy?
GFR and creatinine because these would change only in PROGRESSED kidney disease- its too late to prevent then
mechanism of diabetic nephropathy
1) Hypertension and hyperglycaemia
2) hypertension in glomerulus
3) PROTEINUREA
4) fibrosis of GLOMERULUS and INTERSTITIAL space
5) GLOMERUAL FILTRATION DECLINE
6) renal failure
what treatment should people with microalbuminurea/ porteinurea get?
ARB or ACEi even if normotensive
these drugs imptove progression of diabetic nephropathy AND reduce bp
NEVER FORGET HOLLISTIC APPROACH- popping them on a drug is not enough bc still theres risk for cardiovascular disease so need to control other facotors, smoking ect.
specific OTHER things to consider in diabetic nephropathy other than drugs
Aim for good glycaemic control (HbA1c <53 mmol/mol)Reduce
BP (aim <130/80 mmHg) usually through ACEi or A2RB
Stop smoking
Start an SGLT-2 inhibitor if T2DM?
how is angiotensin 2 made?
1) angiotensinogen from liver
2) stimulated by renin from the kidney to turn into angiotensin I
2) STIMULATED BY ACE to turn into angiotensin II
where does angiotensin II act on and what are the effects?
on angiotensin receptors in
1) blood vessels for vasoconstriciton
2) zona glomerulosa of adrenal cortex for aldosterone secretion
what are 2 types of antihypertensives?
ACEi : ace inhibitors and ARBs - angiotensin receptor blockers
what do the ACEi drugs and ARBs drugs names end with?
-pril
-sartan
what is the name of small vessels supplying nerves?
vasa nervosum
when do you get neuropathy (pathophysio)
when vasa nervosum get blocked
most common cause of neuropathy and therefore lower limb amputation
diabetes mellitus
unique risk factors for diabetic neuropathy
age
height (longer nerves in lower limbs of tall people)
presence of diabetic retinopathy
why is neuropathy more common in feet?
bc longest nerves
why is diabetic neuropathy in feet clinically relevant
1) can be painful
2) patients may not sense injury-> infection
what are the 2 main factors u need to check for in diabetic foot
factors you want to check for:
1) sensation
2) blood flow
how do you check for these factors in diabetic foot
1) inspect- look for deofrmity - ulceration
2) sense test with monofilament - ankle jerks
3) asses foot pulses: dorsalis pedis and posterior tibial
what are patients with reduced sensation to feet and reduce vascular supply to feet at risk for and what are the med names of the two thongs mentioned above?
peripheral neuropathy
peripheral vascular disease
risk of ulceration
peripheral neuropathy management
. Regular inspection of feet by affected individual
2. Good footwear
3. Avoid barefoot walking
Podiatry and chiropody if needed
periptheral neuropathy with ulceration management
Multidisciplinary diabetes foot clinic
Offloading
Revascularisation if concomitant PVD
Antibiotics if infected
Orthotic footwear
Amputation if all else fails
2 other types of neuropathy
mononeuropathy
autonomic neuropahty
what are 2 common forms of mononeuropathy
1) drop of one wrist. leg
2) 3rd CN/ occulomotor PALSY: eye looks down and out (think eye drops like the rest)
what is autonomic neuropathy
damage to sympathetic and parasympathetic nerves along multiple systems: cardiovascular, GI, bladder
GI sympotms of autonomic neuropathy and problems it causes with diabetes
diarrhoea
constipation
vomiting + nausea (late GASTRIC emptying )- CHALLENGING with short acting glucose doses
CARDIO sympotms of autonomic neuropathy
postural hypotension - colapse when standing
sudden cardiac death - cardiac autonomic supply
effect of hyperglycaemic management on cardiovascular disease (MACRO vascular complic)
MINOR EFFECT
modifiable RISK factors for macrovascular disease
dyslipidaemia
central obesity
diabetes mellitus
smoking
hypertension
non modif risk factors for macrovascular disease
age
sex
birth weight
genes
Managing cardiovascular risk in diabetes mellitus
Smoking status – support to quit
Blood pressure < 130/80 mmHg if microvascular complication or increased metabolic risk (NB often needs multiple agents)
Lipid profile – total chol <4, LDL <2
Weight – discuss lifestyle intervention +/- pharmacological treatments
Annual urine microalbuminuria screen – risk factor for cardiovascular disease
