CVD risk assessment tools

A 40-year-old man attends to discuss his recent cholesterol test. He asks you if he should start cholesterol-lowering medication. Which of the following clinical parameters are used in the QRISK3 calculation to determine cardiovascular risk?

• Personal history of impaired fasting glycaemia

• FH of IHD in a 1st degree relative <70 years

• Personal history of liver disease

• Personal history of rheumatoid arthritis

• Personal history of ischaemic heart disease

The cholesterol : HDL ratio rather than serum cholesterol level is used in QRISK3, and a FH of angina or heart attack in a 1st-degree relative aged <60 is used. Diabetic status is required in the QRISK3 calculation, although no consideration is given to impaired fasting glycaemia.

References

• QRISK3 (risk of heart attack or stroke over the next 10 years)

• QIntervention (how that risk could change with interventions)​

• JBS3 (Joint British Societies for the prevention of CVD risk calculators)

Cholesterol / Familial hypercholesterolaemia

Which ONE of the following lipid measurements is most useful, in association with DNA testing, to identify patients who have FH?

1. High density lipoprotein (HDL)

2. Low density lipoprotein cholesterol (LDL-C)

3. Total cholesterol

4. Triglycerides

5. Very low density lipoprotein (VLDL)

Current guidelines recommend using cascade testing, which combines DNA testing and LDL-C concentration measurement to identify affected first, second-degree (and when suitable, third-degree) relatives of those with a clinical diagnosis of FH.

A 45-year-old man is concerned about his cardiac health. O/E, he has tendinous xanthomata of his hands. You carry out a lipid profile including total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). Which of the following lipid profile results is part of the Simon Broome diagnostic criteria for identifying individuals with familial hypercholesterolaemia?

• TC > 5.3 mmol/l and LDL-C > 2.2 mmol/l

• TC > 6.0 mmol/l and LDL-C > 3.1 mmol/l

• TC > 6.7 mmol/L and LDL-C > 4.0 mmol/l

• TC > 7.5 mmol/l and LDL-C > 4.9 mmol/l

• TC < 8.2 mmol/l and LDL-C > 5.8 mmol/l

The importance of identifying FH in individuals of all ages cannot be overemphasised. In the UK, heterozygous FH affects approximately 110,000 people. If left untreated, FH leads to a >50% risk of CHD in men by the age of 50 years and at least 30% in women by the age of 60 years. Homozygous FH is rare, with symptoms appearing in childhood, and associated with early death from CHD. Using the Simon Broome diagnostic criteria for identifying individuals with FH an individual can be diagnosed with definite FH if they have cholesterol concentrations as follows:

• Child/young person: TC >6.7 & LDL-C >4.0

• Adult: TC >7.5 & LDL-C > 4.9

and tendinous xanthomas, or evidence of these in 1st or 2nd-degree relative

or,

• DNA-based evidence of an LDL-receptor mutation, familial defective apo B-100, or a PCSK9 mutation

A person can be diagnosed with possible FH if they have cholesterol concentrations as above and at least one of the following.

• FH of MI <50 in 2nd-degree relative or <60 in 1st-degree relative

• FH of raised TC >7.5 in adult 1st- or 2nd-degree relative or >6.7 in child, brother or sister >16 years

References

• Familial hypercholesterolaemia: identification and management (NICE CG 71). 2008 (updated 2019); Familial hypercholesterolaemia (CKS)

• Cholesterol (NHS Choices)

Lipid modification / Statins

• Lipid modification - CVD prevention (CKS)

• Statins (NHS Choices)​

• Interpretation of the evidence for the efficacy and safety of statin therapy (Lancet, 2016)