Cholesterol*

What is cholesterol?

  • a lipid (type of fat) plays essential physiological role in the body

Where does it come from?

  • very little in food, eggs offal shellfish high
  • saturated fat turned into cholesterol in liver

Why do we need cholesterol?

  • without cholesterol the body won’t work
  • like specialised bricks it is needed for forming all cell membranes
  • insulates nerve fibres, allowing chemical messages to travel
  • synthesis hormones

Why is it bad?

  • coronary artery disease
  • disease of arteries

Need to know something about Lipoproteins – the molecules transport cholesterol

Cholesterol on it’s own not good enough

  1. Low density lipoproteins (LDL-C) is BAD cholesterol
  2. High density lipoproteins (HDL-C) is GOOD cholesterol
  3. Triglycerides

Plaque formation

  • Atherosclerosis starts with “fatty streaks” due to oxidised (LDL-C) BAD clinging to walls releasing extracellular cholesterol

Data

  • Average Total Cholesterol level in UK –> 5.8 mmol/l
  • Average Total Cholesterol Northumberland –> 6.5 mmol/l
  • Healthy cholesterol range Total cholesterol less than 5.2 mmol/l
  • LDL cholesterol less than 3.0 mmol/l
  • HDL cholesterol more than 1.15mmol/l

Ideal levels

Healthy levels for different types of cholesterol
Result Healthy level
Total cholesterol 5 or below
HDL (good cholesterol) 1 or above
LDL (bad cholesterol) 3 or below
Non-HDL (bad cholesterol) 4 or below
Triglycerides 2.3 or below

Abnormal value – What should we do?

  • order lipid profile
  • total cholesterol (TOTAL-C), HDL-C level, Cholesterol / HDL-C ratio

Confused?

So am I

Primary prevention of CHD

Government decided only those with risk of CHD events greater than 30% over 10 years warrant treatment

So what should we be doing?

Secondary Prevention EASY –> all know what to do?

  • total cholesterol below 5 mmol/l

Primary Prevention NOT so EASY – High cholesterol levels alone poor predictor CHD

  • identify risk assessment
  • total cholesterol > 5mmol/l
  • QRISK2 calculator – work out Cardiovasc risk score

Generally Abnormal Values are:

  • LDL cholesterol > 4 mmol/litre
  • HDL cholesterol <1 mmol/litre
  • Total cholesterol:HDL cholesterol >6.5 mmol/litre

National Service Framework (NSF) for Coronary Heart Disease (CHD)

  • primary care to achieve goals coronary heart disease prevention
  • including lipid modification

Cost of achieving CHD NSF lipid-lowering goals £31,000 to £52,000 per GP

Currently

  • majority English adults have adverse lipid levels
  • few people on lipid-lowering drugs as currently recommended

Secondary Prevention of CHD

This group most to gain from therapy

  • smoking
  • weight exercise
  • blood pressure below 140/85
  • low dose aspirin 75 mgs
  • statins cholesterol less than 5mmol/l
  • ACE inhibitors
  • Beta blockers
  • Warfarin / aspirin for atrial fibrillation
  • diabetes glucose blood pressure

Currently

  • only 2.5% adult population taking lipid lowering drugs (statins)
  • rates low among high risk patients for primary prevention
  • fewer than 4% individuals eligible for primary prevention receive statins
  • less than 30% of established CHD are taking statins
  • total target cholesterol levels are less than 50% in those on treatment

Benefits of Statins

How do they work

Biosynthesis precursors — HMG-CoA reductase enzyme –> cholesterol

Statins act here

  • demonstrated in 5 randomised placebo-controlled trials (30,000) 4S, WOSCOP, CARE etc.
  • results suggest risk reduction 34% coronary events in primary prevention

30% coronary events in secondary prevention

  • statin therapy taken for 5 years seems to reduce stroke by 25% too

Examples

Mrs Shirley S Age 67 years

Clinical data: Hypertension Probable angina Atenolol Fasting

  • Cholesterol 7.2mmol/l 3.2 – 6.5
  • Triglyceride 3.66mmol/l 0.79 – 1.97
  • HDL-CHOL. 1.0 mmol/l 1.2 – 1.7
  • CHOL/HDL RATIO 7.2
Mrs Felicity H Age 52 years

Clinical Data: Hypercholesterolaemia Brother died MI Heart Failure

  • Cholesterol 8.2mmol/l 3.2 – 6.5
  • Triglyceride 0.88 mmol/l 0.79 – 1.97
  • HDL-CHOL 1.6 mmol/l 1.2 – 1.7
  • CHOL/HDL RATIO 5.1
  • LDH-CHOL 6.2 mmol/l 0.0 – 4.2
Mr John M Age 62 years

Clinical Data: C.A.B.G.

  • Cholesterol 7.4mmol/l 3.2 – 6.5
  • Triglyceride 1.41 mmol/l 0.79 – 1.97
  • HDL-CHOL 1.3 mmol/l 1.2 – 1.7
  • CHOL/HDL RATIO 5.7 mmol/l

A cholesterol protocol

Secondary prevention –> Total cholesterol below 5 mmol/l (proven CHD)

Primary Prevention (risk >30%)–> Total cholesterol to 5 mmol/l or reduce by 30% (which greater)

  • USE STATINS OR
  • LDH cholesterol to <3 mmol/l or reduce by 30% (which greater)
  • OR Total cholesterol:HDL ratio (use Sheffield table)
Scroll to Top