Management of hyperlipidemia Flashcards
lipid metabolism?
- chylomicrons transport fats from intestinal mucosa to liver
- in the liver chylomicrons release TGs, come cholesterol and they become LDLs
- LDL then carries fat and choleseterol to body’s cells
- HDLs carry fat and cholesterol back to liver for excretion
- when oxidized LDL cholesterol increases and atheroma formation occurs in walls of arteries, which causes atherosclerosis
- HDL cholesterol is able to go and remove cholesterol from atheroma
What is happening in atherosclerosis?
inflammatory factors are being released
Primary (hereditary) causes of dsylipidemia?
- familial hypercholesterolemia: codominant genetic disorder, occurs in heterozygous form, occurs in 1-500 individuals, mutation in LDL receptor, they are absent or defective, resulting in unregulated synth. of LDLS, high risk for atherosclerosis, tendon xanthomas (75% of pts), tuberous xanthomas, and xanthelasmas of eyes
- familial combined hyperlipidemia: autosomal dominant, increased secretions of VLDLs
- dysbetalipoproteinemia: affects 1-10,000, results in apo E2, a binding defective form of apoE (which usually plays important role in catabolism of chylomicron and VLDL), increasaed risk for atherosclerosis, peripheral vascular disease, tuberous xanthomas, striae palmaris (thick skin on palms and soles)
What are xanthomas?
- soft, yellow skin plaques or nodules that contain deposits of lipoproteins inside histiocytes, especially likely to be found on pt with hyperlipidemia
WHere are tuberous and tendinous xanthomas found?
achilles tendon, knees, elbows, ankles
Secondary causes of hyperlipidemia?
- contribute to most cases of dyslipidemia in adults
- most common cause in developed countries: sedentary lifestyle with excessive dietary intake of saturated fat, cholesterol, and trans fats
- smoking
- uncontrolled DM II, metabolic syndrome
- hypothyroidism
- liver and renal disease
- corticosteroid use
- progestin use
- anabolic steroid use
- ETOH use/abuse
What requirements must be met for metabolic syndrome?
Must meet 3 of the following criteria:
- abdominal obesity (>40 in men, >35 in women)
- high TG level (>150)
- low HDL (130/84 mm Hg
- impaired fasting glucose level > 100
Examples of monunsaturated fats, and effect on cholesterol levels?
- olive oil canola oil, cashews, almonds, avocados
- lowers LDLs and raises HDL
Polyunsaturated fats:
corn, soybean oil, fish oil
- lowers LDLs and raises HDL
Saturated fats?
- whole milk, butter, cheese, red meat, coconut milk
- raise both HDl and LDL
Trans fats
- process food - raises LDLs
5 major steps to ID pt at risk for hyperlipidemia?
- 1 obtain fasting lipid profile
- 2 ID if there are any CHD risk equivalents
- 3 ID if any major CHD RFs other than LDL
- 4 if pt has CHD risk equivalent, or 2 or more risk factors (other than LDL), calculate 10 yr risk of CHD
- 5 determine risk category, in order to establish the LDL goal, when to initiate therapeutic lifestyle changes, and when to consider drug therapy
Why are these steps so impt in preventing CHD?
- optimum tx of lipids helps in primary and secondary prevention of CVD
- generally hyperlipidemia is asx
- CVD is still #1 killer in US has been since 1900
- 50% of CVD dx and 15% of CVD deaths are in pts
Guidelines for hyperlipidemia?
- ATP III of national cholesterol education program- natl heart lung and blood institute NIH:
- summarized recommendations for management of high serum cholesterol
- ATP III based on epidemiologic observations that showed graded relationship b/t total cholesterol concentration and coronary risk
- recommendations summarized based on: primary prevention (absence of disease) and secondary prevention (presence of preexisting CHD)
Step 1 of guidelines: check lipid panel
- healthy adults, no RFs - every 5 years starting at 20
- obtain fasting serum lipid profile consisting of total cholesterol, LDL, HDL
What are the lipid panel goals?
- total cholesterol: 40 in men, >50 in women, >60 cardio protective
- TGs
Goals for lipids?
LDL 60 high
serum TGs: 500 think pancreatitis
Step 2: ID CHD risk equivalents: these are?
- diabetes
- other forms of clinical atherosclerosis disease: clinical CHD, AAA, PAD, sx CAD
Guidelines for diabetes being a risk equivalent?
- men over 40 with DM II and any other risk factor or over 50 with no RFs
- women over 45 with DM II and any other CHD risk facotr or over 55 w/o risk factors
- men or women of any age who have had DM (I or II) for over 20 years if they have risk factor or more than 25 years w/o risk factor
Step 3: determine major risk factors of CVD? (other than LDL)
- smoking
- HTN (BP>140/90 or antiHTN meds)
- low HDL 45 and women: > 55
Step 4: assessment of risk?
- for persons without known CHD, other forms of atherosclerotic disease or diabetes:
- count number of risk factors
- use framingham scoring for persons with >2 risk factors to determine absolute 10 year CHD risk
- first look at age, TC, HDL, systolic BP, smoking status, add up pts
Step 5: determine risk category
- CHD or CHD risk equivalent (10 year risk > 20%) -want LDL 130
- 2 or more risk factors (10 yr risk 130 initiate therapeutic lifestyle changes, drug therapy >130
- 0-1 risk factor (10 yr risk 190 drug lowering therapy
Secondary prevention recommendations (LDL goals, drug therapy)
- intensive statin therapy in pts with acute coronary sndrome recommended as initial therapy
- pts at very high risk for CHD events should be targeted for LDL below 70 (if unable to achieve by statin alone, use second agent)
- usualy risk pt with stable CHD unable to achieve LDL goal alone with statin 0 should have 2nd agent added
- if they don’t tolerate a statin, they should be tx with another lipid lowering agent
Who is at very high risk for CHD events?
- est coronary heart disease + mult major risk factors (diabetes) or severe or poorly controlled risk factors (cont. smoking) or mult risk factors of metabolic syndrome (esp TGs>200 + non HDL-C > 130 plus HDL less than 40 or acute coronary syndrome
Goals for very high risk pts?
- more intesnive lipid lowering therapy
- LDL belwo 70
- sig. reduction in all cause mortality (RRR 13%), death from heart disease or related blood vessel disease (RRR 17%), and major CV events (RRR 24%) at levels less than 100 mg/dL
- most observers are in strong support of LDL below 70 in high risk pts
After categorizing what pr’s RRR is now what?
- initiate therapeutic lifestyle changes alone (diet change should lower TGs)
or - TLC and drug therapy: tx hyperlipidemia with drug therapy (decision based on LDL level)
Dietary and lifestyle changes will have what type of impact?
- may decrease LDL by 10%
- total fat
What are statins?
- HMG - CoA reductase inhibitors
- most heavily used class of lipid lowering drugs
- excellent agents at lowering LDL cholesterol and decreasing associated morbidity and mortality rates for primary and secondary prevention of CAD
- LDL lowering 20-60%
- can increase HDL (crestor mostly) and lower TGs
- well tolerated by most pts