SINGAPORE - I have many patients who come in for health screening.
The standard blood tests that we use always includes a fasting lipid profile which tells us about the patient's cholesterol levels.
When it is time to review the results with the patient, I will invariably be asked whether his cholesterol level is high and what to do about it.
Should those with high cholesterol levels panic and immediately try to starve themselves and give up their favourite laksa and char kway teow?
There is now a new set of guidelines to follow.
In late November last year, the American Heart Association and the American College of Cardiology issued radically new guidelines for cardiovascular risk assessment as well as for the control of cholesterol levels.
They have identified four groups of patients who will definitely benefit from taking a cholesterol-lowering drug called a statin.
The group that is considered the "no-brainer" group for doctors to prescribe statins to are those who already have heart disease, stroke or vascular disease of the legs.
This group has always been considered to have a high risk of another heart attack or stroke. Therefore, statins are recommended.
The next high-risk group is those with diabetes. They must be between 40 and 75 years of age and their low-density lipoprotein (LDL) cholesterol or "bad" cholesterol level should be between 70mg/dL and 189mg/dL.
THE 'NEW NORMAL'
Traditionally, a bad cholesterol level of less than 100 mg/dL is considered optimal.
But what the new guideline implies is that the "new normal" should be less than 70mg/dL - and I estimate that more than half of all Singaporeans have a higher LDL than that.
The third group of patients who would benefit from taking statins are those whose LDL exceed 190mg/dL.
This group of people is likely to have familial hyperlipidaemia, so their high cholesterol levels are due to their genes.
No matter how much they cut back on high-cholesterol food, their LDL levels will remain high as their livers are happily producing the substance.
They will need a statin to reduce their LDL levels.
The last group are healthy individuals whose LDL ranges from 70mg/dL to 189mg/dL, but they have other risk factors that will increase their likelihood of suffering heart attacks or stroke.
These risk factors include being Caucasian, being a smoker, having high blood pressure and currently being treated for high blood pressure and diabetes. Age and gender also play a part.
The American Heart Association recommends using a risk calculator. By entering all the person's variables into the equation, doctors get an answer for that person's risk of heart attacks.
If the risk adds up to 7.5 per cent or more, it is considered high. The person will then benefit from taking a statin.
Let me explain with an example. A 50-year-old Chinese man who does not smoke is found to have a blood pressure of 140/90mmHg and total cholesterol level of 210mg/dL, of which his high-density lipoprotein or good cholesterol level is 40mg/dL.
Based on the readings, he has a 2 per cent 10-year-risk of developing a heart attack or stroke.
This means that he is in the low risk category and will not need cholesterol treatment.
Cholesterol treatment itself has also been simplified with the latest guidelines.
As outlined earlier, all four groups of patients mentioned will benefit from taking statins to keep their cholesterol levels in check.
The recommendation is to prescribe either low to medium doses of a strong statin such as rosuvastatin, or high doses of a weaker statin like atorvastatin or simvastatin.
The most common concern that most of my patients have is whether the statin will cause bad side effects.
There is a common misconception among patients that cholesterol drugs are extremely toxic to the body and can cause much internal damage.
Statins have been studied for the last 20 to 30 years and are known to cause muscle pain, muscle weakness, inflammation of the liver and, very rarely, kidney failure due to severe muscle breakdown.
The good news is, the lower the dose of the statin, the lower the likelihood of side effects.
I also tell them that side effects can be monitored and readily picked up by regular blood tests. They can also be reversed if the statin treatment is stopped.
Some of my patients also ask if they can take the medication just weekly, or once every three days.
But there is no evidence that there will be protective effects if one takes the drug less frequently.
In fact, the cholesterol-lowering effects wear off pretty quickly and if the patient stops taking the statin for three or four days, his bad cholesterol level can bounce back.
We are in a good situation as the authorities have clarified who will benefit from taking a statin.
If you do not belong to any of these four groups, you can now heave a sigh of relief.
Dr Ng is a consultant cardiologist at Novena Heart Centre. He specialises in treating heart failure. He was the director of the heart failure programme at the National Healthcare Group from 2003 to 2007.
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