Familial hypercholesterolaemia is an inherited disorder that markedly increases the “bad” LDL cholesterol in the blood and, in most cases, causes deposits of cholesterol in tendons and causes premature heart disease.
Basic management consists of lifestyle interventions and medication. Special treatments such as plasmapheresis may be required in unusual situations, for instance when FH patients don’t respond well to other treatments.
We know that lifestyle is important in the management of FH because Japanese FH patients on average live 10 years longer than their European counterparts with the same diagnosis. The Japanese low-fat diet with its emphasis on marine products could be the reason why the Japanese develop coronary disease at a later stage.
Lifestyle management is advised for pregnant and nursing women and for children from the time solid foods are first introduced. The whole family should follow this eating plan.
Other lifestyle habits to follow:
- keep an eye on kilojoules so that you maintain your ideal body weight
- exercise regularly
- you should not smoke at all and should also avoid passive smoking
- In small amounts, alcohol is not unhealthy.
2. Medication: statins
There is no doubt that medication can decrease the risk of a heart attack dramatically.
Statins don’t cure FH but in combination with lifestyle interventions, they powerfully reduce the risk of heart disease, the main cause of death in FH. Within a decade of introducing statins in Britain, vascular events in people with FH decreased by 75%. Medication is required for everyone with FH.
In the absence of detailed studies of timing and intensity of cholesterol treatment, the following are regarded as the minimal requirements in treatment:
- Statins which have a short duration of action are normally taken in the evenings for best results as the bulk of the manufacturing of cholesterol in the body occurs at night.
- Atorva and rosuvastatin are long-acting statins that may be taken any time of the day.
- All adult men over 25 years should be treated.
- In women the use of statins could be delayed until the family is complete. This is because of the later onset of cardiovascular-disease complications and the possibility of pregnancy. Treatment can also be stopped for planned pregnancies.
- The aim is to achieve an LDL cholesterol concentration of less than 3 mmol/L in all FH patients, and even lower in patients who have suffered vascular events.
- The treatment of children has not been fully researched. Previously it was thought not to be necessary to place heterozygous FH children on statins, but studies have shown that statins are safe for them to take and lower their cholesterol. Boys and girls at a much higher risk than average should therefore probably be treated. The doctor will make the decision to treat children with statins, based on multiple risk factors. It is best to have these decisions made by specialists at specialised centres such as lipid clinics.
- All other risk factors such as blood pressure and diabetes should also be treated.
If your targeted LDL concentration is not achieved by statins alone, you may have to take additional drugs with different mechanisms of action. Your doctor may prescribe ezetimibe, a drug that is convenient to use and significantly lowers LDL cholesterol by lowering cholesterol absorption.
Cholestyramine, a powder that’s not absorbed, is less convenient but also significantly reduces LDL cholesterol. It wastes bile acids so that cholesterol has to be used to replace these losses.
The B vitamin niacin lowers LDL and has favourable effects on HDL, triglycerides and Lp(a), but may not be easy to take because it has flushing as a side effect. Flush-free preparations should be available in South Africa soon. A recent development is the combination of a flush inhibitor (laropiprant) with niacin.
Fibrates are other drugs that could be useful if there is an additional problem with high triglycerides or low HDL, but they don’t have a powerful effect on LDL.
In a small proportion of heterozygous FH patients and in almost all cases of homozygous FH, plasmapheresis is required to achieve control.
Plasmapheresis is an expensive procedure, requiring a special machine and nursing staff to cleanse the blood of cholesterol over about four hours. The cholesterol concentration decreases dramatically but rebounds over the next fortnight, so that repeat procedures are required every 14 days.
Plasmapheresis is life-saving but is available to only a few South African patients. Newer treatments are under investigation at specialised centres in South Africa.
Compiled with the help of and reviewed by Prof David Marais, head of the Lipid Clinic at Groote Schuur Hospital and the University of Cape Town, September 2010.