Dr Graham Bayly, Consultant Biochemistry and Metabolic Medicine, Lipid Clinic, Royal Infirmary Bristol
What are the issues in diagnosing and managing these patients?
- Primary Care Practitioners are important for appropriate referral of these patients.
- Patients that should be considered for referral include:
- Patients suspected of having familial hypercholesterolaemia (FH) (total cholesterol >8mmol/L and or a family history of premature CHD or hyperlipidaemia in a first-degree relative).
- Patients with mixed dyslipidaemia, raised cholesterol and raised triglycerides >10.
- Patients at high CV risk not reaching cholesterol targets/intolerant to statins.
- Those who experience an event while on lipid-lowering therapy and there is concern about intensifying therapy.
- What is the appropriate cholesterol target for individual patients with progressive CVD?
What are the implications and answers?
- Patients with raised cholesterol and triglycerides <10 mmol/L should be treated first-line with statins.
- Severe triglyceridaemia >10mmol/L should be treated with fibrates as first-line therapy to prevent the development of acute pancreatitis. Secondary causes of hypertriglyceridaemia should be addressed (e.g. becoming diabetic, alcohol intake and obesity).
- In statin intolerance, use of an alternative statin of similar potency, a ‘drug holiday’ and rechallenge or a lower dose can be effective interventions. Rosuvastatin should be considered as it has a good side-effect profile. It is always worthwhile to retry statin therapy, but agents such as the PCSK9 inhibitor alirocumab can be considered (as in the ODYSSEY trial) for patients intolerant to atorvastatin.
- Cholesterol targets are very conservative and studies with PCSK9 inhibitors have shown that cholesterol levels <1.8mmol/L are safe.
Diagnosing and treating FH
- Familial hypercholesterolaemia is inherited in an autosomal dominant manner.
- The benefits of determining the presence of FH are better acceptance by the patient of the diagnosis and better compliance with therapy.
- If the patient carries the mutation, at every level of cholesterol, he/she has a higher risk of experiencing an event.
- In these FH patients, PCSK9 inhibitors offer the opportunity to target lower cholesterol levels (<1.3mmol/L) and achieve normal life expectancy.