Block 1: dyslipidaemia Flashcards
Dyslipidaemia: overview
- Relationship between total and LDL-C levels and CAD, CVD and peripheral vascular disease
- 50% of the population, highly preventable
- Majority of patients with atherosclerosis have dyslipidaemia
- Asymptomatic
- Too much cholesterol can build up in the arteries causing atherosclerosis
Progression of dyslipidaemia
- Initially dyslipidaemia: no symptoms, reversible
- Atherosclerosis: symptoms, reversible
- Symptoms, non-reversible: can develop Ischaemic heart disease, CVD, Peripheral vascular disease
Dyslipidaemia bloods (lipid profile)
- Total Cholesterol (Desirable <5 mmol / l)
- Low density Lipoproteins (LDL) (Desirable <2.5 mmol / l): ‘Bad cholesterol’
- High Density lipoproteins (HDL) (Desirable > 1.2 in women and > 1 in men): ‘Good cholesterol’
- Triglycerides (Desirable < 2.5 mmol / l)
- Total cholesterol/ HDL Ratio (Desirable < 4 )
- Total cholesterol measures the combination of LDL, HDL, and VLDL. VLDL is a precursor of LDL, the bad cholesterol.
- Others: Very low density lipoproteins (VLDL), Lipoprotein A, Apolipoproteins
LDL
- Carries most of the cholesterol in the blood
- Combines with other substances to clog arteries
- Due to diet high in saturated and trans fats
- Should be <2.5 but in heart disease should be lower
- HDL helps remove LDL. Want high HDL
Triglycerides
- The body converts excess calories, sugar and alcohol into triglycerides.
- Type of fat that is carried in the blood and stored in fat cells
- Increases risk of metabolic syndrome which is linked to heart disease and diabetes
Causes of dyslipidaemia
- Primary: Genetic dyslipidaemia (Familial Hypercholesterolaemia)
- Secondary: T2D, Nephrotic syndrome, Hypothyroidism, obesity, smoking, lifestyle
Familial hypercholesterolaemia: 3-4x risk of heart attack and stroke
Risk factors for high cholesterol
- Diet high in saturated fats and cholesterol
- Family history
- Being overweight or obese
- Age
- Diabetes
- Physical inactivity, smoking, alcohol
Ways to lower cholesterol: dietary modification
- Saturated fats (animal fats and oils) raise LDL and trans fats increases LDL and reduces HDL
- Reduce diet of baked goods, fried food and margarine
- Unsaturated fats can lower LDL with other diet changes, they are in avocados, olive oil and peanut oil
- Moderate alcohol intake, stop smoking
Other ways to lower cholesterol: lifestyle, medicine
- Lifestyle: loose weight, stop smoking, increase physical activity
- Statins: either lipid soluble (Atorvastatin) or water soluble (Rosuvastatin). Decrease LDL and TG, increase HDL
- Fibrates, Ezetimibe, Omega 3 fatty acids
- Bile acid sequestrants
- PCSK 9 inhibitors, Inclisiron
Initial tests for dyslipidaemia
- Full lipid profile
- BMI: weight and hight
- Blood pressure
- Fasting glucose
- Bloods: Hba1c, thyroid function tests, U&E, LFT
Signs of hyperlipidaemia
- Tendon xanthomata: nodules that develop in the hands and Achilles tendon
- Xanthelasma: nodules on the eyelids
- Premature corneal arcus: bluish rims surrounding the iris
Genetic dysipidaemia
- Familial combined hyperlipidaemia: increased LDL, triglycerides or both
- Heterozygous familial Hypercholesterolaemia: increased LDL
- Polygenic Hypercholesterolaemia
- Familial Hypertriglyceridemia
Familial Hypercholesterolaemia
- Family history of early cardiac event
- High LDL cholesterol, above 190 in adults and 160 in children
- Autosomal dominant inheritance, if you have it children have 50% chance of getting it
- 1:200
When to suspect FH
- High LDL >5
- Early cardiovascular event: in themselves or close relatives
- Strong family history
- Stigmata: Tendon xanthoma, Arcus Lipidalis
Testing for FH
- Risk calculated using Dutch lipid scoring system. If >8 definite FH, 6-8 probable FH, 3-5 possible FH, <3 unlikely FH
- Confirmatory test: gene sequencing, once confirmed family members are screened (family cascading)
- Simon Broom criteria: helps confirm FH
Management of FH
- Life style modification: better diet and increase exercise
- Family cascading: test rest of the family
- Statins
- Ezetimibe
- PCSK-9 inhibitors: Alirocumab, Evolucumab. Work on LDL receptors to destroy more LDL in the liver
- Inclisiron: reduces production of PCSK-9
- Medication aim: bring LDL as low as possible <2.5
Diabetic neuropathy
- When it causes damage to your nerves
- 4 types: peripheral neuropathy, sensory neuropathy, autonomic neuropathy, motor neuropathy
- Treatment: monotherapy with antidepressant drugs inclusing tricyclics (amitriptyline, hydrochloride), duloxetine, Can use antiepileptics (pregabalin and gabapentin)
- For diarrhoea use tetracycline or codein phosphate. In gastroparesis use erythromycin
Symptoms of diabetic neuropathy
- Peripheral: pain in hands or feet
-Sensory: tingling, numbness, inability to feel pain/temperature, shooting pain, loss of coordination - Autonomic: gastroparesis (bloating, constipation, diarrhoea), loss of bladder control, irregular heart beats, impotence
- Motor: muscle weakness
Hyperosmolar hyperglycaemia
Life threatening complication of T2D: severe hyperglycaemia, extreme dehydration, hyperosmolar state and altered consciousness
Often due to concurrent illness
Treatment- IV saline and insulin
Complications: coma, seizure, death
Symptoms: urination, thirst, nausea, dry skin
No ketones in blood
Types of thinking
- Type 1: fast paced intuitive, unconscious. Processes information quickly. Influenced by emotions, experiences and memories
- Type 2: deliberate effort, concentrated thought. Processes information slowly. Is influenced by facts, logic and evidence