Fasting samples (14 h) are required for interpretation only of triglyceride values. The sample for plasma cholesterol does not need to be taken fasting but may be spuriously elevated by 10% for up to 15 min due to exercise prior to venepuncture.
Possible secondary causes of hyperlipidaemia
||Raised cholesterol & triglycerides
|Hypothyroidism Liver disease
|High alcohol intake
NICE Guidance #94: Statins for the prevention of cardiovascular events
- Statin therapy is recommended for adults with clinical evidence of CVD.
- Statin therapy is recommended as part of the management strategy for the primary prevention of CVD for adults who have a 20% or greater 10-year risk of developing CVD. This level of CVD risk should be estimated using an appropriate risk calculator, or by clinical assessment for people for whom an appropriate risk calculator is not available (for example, older people, people with diabetes or people in high-risk ethnic groups).
- Within the recommendations outlined in Section 1.1.and Section 1.2, the decision whether to initiate statin therapy should be made after an informed discussion between the responsible clinician and the individual about the risks and benefits of statin treatment, and taking into account additional factors such as comorbidities and life expectancy.
Please note the following:
- The target is to reduce total cholesterol level to <4 mmol/L.
- These guidelines do not apply to patients without a clear history of myocardial infarction or angina (i.e. primary prevention), nor are they intended to restrict individual clinical judgement.
- Attention should also be given to other established risk factors such as smoking, obesity and lack of exercise.
- Fasting sample and full lipid profile are preferable prior to initiating therapy.
- Liver function tests and thyroid function tests should be checked prior to starting treatment.
- A random triglyceride level of > 3.5 mmol/L may result from alcohol excess, diabetes mellitus, hypothyroidism, sedentary lifestyle, or combined familial hypercholesterolaemia. A repeat fasting sample with appropriate additional tests is recommended.
- Cholesterol levels fall transiently after myocardial infarction or any other illness and should be routinely determined on admission with repeat estimation no earlier than 3 months later if initially < 5.0 mmol/L. In the event of an initial level > 5.5 mmol/L the above advice applies.
- During therapy with a statin routine monitoring of liver function tests and creatinine kinase is not required unless symptoms of muscle pain or weakness occur. Patients should be routinely advised to report any unexpected symptoms.
- Fibrates are excreted by the kidney and should be used with caution in renal impairment
Cholesterol targets: current recommendations by different bodies
Total Cholesterol < 5 mmol/L (LDL-cholesterol < 3 mmol/L) or reduce by 30% whichever is the greater.
Without established CHD: total cholesterol < 5 mmol/L, LDL-cholesterol < 3 mmol/L
With CHD or diabetes or at high, multifactorial risk: total cholesterol < 4.5 mmol/L, LDL-cholesterol < 2.5 mmol/L
British Hypertension Society (2004)
Lower total cholesterol by 25% or LDL-cholesterol by 30%, or total cholesterol <4 mmol/L or LDL-cholesterol <2 mmol/L, whichever is the greater.
General Medical Services contract (2005)
60% of patients with CHD, diabetes or stroke should have total cholesterol
Total cholesterol < 4 mmol/L and LDL-cholesterol < 2 mmol/L
National Institute for Health and Clinical Excellence (2006)
The threshold of total CVD risk at which statin use is recommended is >/= 20% over 10 years.
- Department of Health. The Coronary Heart Disease National Service Framework: Building for the future - progress report for 2007. London: DoH
- Third Joint Task Force of the European and other Societies. European guidelines on cardiovascular disease prevention in clinical practise. Eur Heart J 2003;24:1601-1610.
- Joint British Societies Guidelines on Prevention of Cardiovascular Disease in Clinical Practice. Heart 2005;suppl V:v1-52