lipid-lowering drugs

Question 1

what is ischaemic heart disease due to?

Answer 1

formation of atheromatous plaques in coronary arteries that associated with dyslipidemias

Question 2

types of lipids in blood

Answer 2

• fatty acids
• triglycerides (non-polar core)
• phospholipids (polar surface)
• cholesterol (polar surface)
• cholesteryl esters (non-polar core)

Question 3

basic functions for chylomicrons

Answer 3

transport TG from gut to adipose tissue and skeletal muscle

Question 4

basic functions of VLDL

Answer 4

transport endogenous TG from liver to peripheral tissues

Question 5

basic functions of LDL

Answer 5

transport cholesterol from liver/intestine to peripheral tissues

Question 6

basic function of HDL

Answer 6

transport cholesterol from periphery to liver to be excreted

Question 7

causes of dyslipidaemias

Answer 7

• hypercholesterolaemia
• hypertriglyceridaemia
• combined both above

Question 8

what is primary dyslipidaemia due to?

Answer 8

diet and genetics

Question 9

what are secondary dyslipidaemia due to?

Answer 9

due to underlying disease eg:

• hyperthyroidism
• diabetes type II
• alcoholism
• chronic renal failure

Question 10

treatments of dyslipidaemia

Answer 10

1. dietary modification
2. reduction of other risk factors
3. lipid-lowering drugs

Question 11

examples of lipid-lowering drugs

Answer 11

• statin
• fibrates
• anion exchange resins
• cholesterol absorption inhibitors
• nicotinic acid
• omega-3-triglycerides

Question 12

define statins

Answer 12

• competitive HMG-CoA reductase inhibitors

- first line for primary and secondary prevention

Question 13

examples of drugs of statins

Answer 13

• simvastatin
• lovastatin
• prevastatin
• atorvastatin

Question 14

functions of statins

Answer 14

• increase hepatic LDL receptors to draw cholesterol from blood stream
• increase clearance of plasma cholesterol
• decrease oxidative stress and vascular inflammation
• increase stability of atherosclerotic lesions
• slight decrease TG and increase HDL
• immune suppression
• protection against sepsis

Question 15

side effects of statins

Answer 15

• myalgias
• GI disturbances
• raised liver enzymes
• rarely severe myositis

Question 16

examples of drugs of fibrates

Answer 16

• gemfibrozil

- fenofibrate

Question 17

functions of fibrates

Answer 17

1. decrease VLDL and TG
2. as PPARs agonists:
   - increase fatty acid oxidation in liver, striated muscle
   - increase expression of lipoprotein lipase, apoA1 and apoA5
   - anti-inflammatory effect via decrease TNF

Question 18

side effects of fibrates

Answer 18

• rhabdomyolysis (damaged skeletal muscle)

- caution in combining with statin can cause above

Question 19

examples of bile-acid binding resins (insoluble in water and stays in gut)

Answer 19

• colestyramine

- colestipol

Question 20

functions of bile-acid binding resins

Answer 20

• decrease cholesterol absorption into gut
• increase endogenous cholesterol metabolism
• increase LDL receptor expression

Question 21

side effects of bile-acid binding resins

Answer 21

• bulky
• unpalatable (toxic)
• constipation
• diarrhoea
• impair absorption of neutral drugs
• severe effects if combine with statin

Question 22

what is ezetimibe?

Answer 22

• specific cholesterol transport inhibitor
• prodrug, glucuronidated in epithelium
• no interaction with warfarin and digoxin
• add-on to statin

Question 23

examples of drugs of nicotinic acid

Answer 23

acipimox (fewer SE but less effective)

Question 24

functions of nicotinic acid

Answer 24

• decrease cholesterol and TG synthesis
• decrease VLDL, LDL
• increase HDL
• usually added to statin or resin

Question 25

side effects of nicotinic acid

Answer 25

- flushing - palpitations - GI disturbance - slight increase of liver enzymes - risk of hepatotoxicity

Question 26

risk groups of getting atherosclerosis

Answer 26

- prior atherosclerotic disease - diabetes mellitus - age >40 - familial hypercholesterolaemia - smoking - hypertension