hyperlipidemia Flashcards
how do lipids travel in blood
- chylomicrons
- VLDL (mainly TG)
- LDL (mainly xol)
- HDL (mainly phospholipids)
what is xol a major rf for?
CVD
relationship between HDL and CVD
HDL correlates inversely with CVD
who needs full fasting lipid profile screening
1. those @ risk of hyperlipidemia if:
- fhx +ve for high xol
- corneal arcus <50yo
- xanthomata/xantholasma
2. those @risk of CVD
- known CVD
- fhx of cvd <60yo
- DM/impaired tolerance of glucose
- HTN
- smoker
- high bmi
- low socioeconomic/asian
main 2 types of hyperlipidemia
- common 1ry hyperlipidemia- )70%), high LDL only
- familial 1ry hyperlipidemia - multiple phenotypes exist
- high risk of CVD,
- refer to specialist
target levels [fasting]
[fasting]
TC: <5mmmol/L
LDL: <3mmol/L
TG: <1.7mmol/L
HDL- men [>1.0mmol] ;; women [>1.2mmol/L]
Hyperlipidaemia: secondary causes
Causes of predominantly hypertriglyceridaemia
- diabetes mellitus (types 1 and 2)
- obesity
- alcohol
- chronic renal failure
- drugs: thiazides, non-selective beta-blockers, unopposed oestrogen
- liver disease
Causes of predominantly hypercholesterolaemia
- nephrotic syndrome
- cholestasis
- hypothyroidism
phenotypes of hyperlipidemia
- common [polygenic] hypercholesteralemia = commonest form!!
- chol: 6.5-9
- TG: <2.3
- high LDL [>4.0]
- may have xanthelasma/arcus
- nb xanthomata dont develop
- familial combined hyperlipidemia
- total chol: 6.5-10.0
- >2.3-12
- high LDL. [>4.0] high VLDL
- low HDL [<1.0]
- here, xanthelasma/xanthomata DO NOT occur
- arcus = oft present
- oft: overweight + have htn
other types of hyperlipidemia to know about:
- familial hyperchylomicronemia [apo protein lipase/apocII deficiency]
- lipidemia retinalis [creamy appearance of retinal vessels]
- hepatosplenomeg
- eruptive xanthomata [yellow/brown papules surrounded by erythematous hole, on but, post thigh, elbow
- heterozygous familial hypercholesterolemia [LDL R deficits] = autosomal dom
- 70% have tendon xanthomata
- fhx of high cholesterol
- dysbetalipoproteinemia
- palmar striae
- tuberoeruptive xanthoma
- prem CAD
- familial hypertryglyceridemia
- chol- 6.5-12
- TG: 3-6
- high VLDL
- often overweight, over 30
- type V hyperlipoproteinemia
- TG: 10-30
- eruptive xanthomata
- lipidermia retinalis
- hepatosplenomegaly
what is mixed hyperlipidemia?
high LDL + high TG
causes:
- T2DM
- metabolic syndrome
- alcohol abuse
- CRF
mx of hyperlipidemia
- identify familial/2ry hyperlipidemia as mx may vary
- lifestyle advice
- aim bmi 20-25
- miterranean diet
- increase exercise
TOP RX PRIORITY: IF HAVE KNOWN CVD RISK [no need to calculate their risk if already high]
i2nd RX PRIORITY: if have:
- CKD
- T1DM
- >10% CVD risk [irrespective of baseline lipid levels]
1st line:
20mg atorvastatin @ night [primary prevention]
80mg atorvastatin [2ry prevention/1ry prevention if have kidney disease]
alternative:
40mg simvastatin [SE: myalgia, myositis, high LFTs, abdo pain, ng: grapefruit and cytochrome p450i’s increase serum conc’s]
TARGET PLSAMA XOL DECREASE OF > 40% IN THO WITH CVD
2ND LINE:
EXETEMIBE [cholesterol absorption inhibitor]
- used in statin intolerance/in combo with statin to achieve max target reduction
3rd line:
ALIOROCUMAB - mab agonist, acts to decrease hepatocyte LDL receptor expression
- [v effective at deceasing LDL
- v expensice
- given as injection every 2 weeks]
BEZAFIBRATE [useful in mixed hyperlipidemias, class: fibrates]
ANION EXCHANGE RESINS EG. COLESTYRAMINE
NICOTINIC ACID [high hdl, low ldl, se’s: severe flushes]
ASPIRIN 300MG
if have high TG ==> best to use fribrates/nicotinic acid/fish oil
when to make referral
- use s/s
- lipid profile
- fhx
- judge likelihood of familial lipid disorder rather than strict cut off values
exclude other causes:
- excess alcohol
- uncontrolled DM
- hypothyroidism
- liver disease
- nephrotic syndrome
when to consider poss familial hypercholesterolemia if have what figures..?
TC >7.5 mmol/L
fhx of prem CAD
arrange specialist assessment if:
TC >9.0
non hdl xol 1.7.5 [even if fhx neg]
urgent specialist review if:
TG = >20mmol/L
- not due to excess alcohol/poor glycemic control
==> if TG 10-20: repeast test w/i 2 weeks + review for 2ry causes of high cholesterol
what does non HDL mean?
non-HDL= TC-HDL
gives a better assessent for risk of heart disease esp if you have high TG
usually base risk depending on LDL levels but sometimes heart attacks occur even when LDL levels are low.
