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Webchat to Dr Clive Weston about Cholesterol |
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The Check Up live webchat about Cholesterol has now finished. Thanks to everyone who sent in questions for Barbara Myers' guest Dr Clive Weston, Consultant Cardiologist, Singleton Hospital, Swansea.
Visit the Check Up page to find out more and to listen again to the programme. Read the full webchat transcript below.
You can also listen again to Dr Weston discussing cholesterol with Graham Easton on Case Notes this week.
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From Elizabeth:
When does the cholesterol level become high? How much can it be reduced by diet, especially if there is a genetic tendency to high cholesterol in a family?
Clive Weston: In general terms a low cholesterol diet will reduce total cholesterol by about 10-15%. A high cholesterol (higher than average in other words) would be approximately 6.5 - that's mmol/l.
From Jacqueline Sisley: I use a 'cholesterol reducing' spead on bread. Is there anything better for you? My cholesterol is 5.8 which I know is high. On the pack it says it will reduce it but which one, the good, or the bad or both?
Clive Weston: It will tend to reduce the LDL (bad) by about 10-15% so that's a good thing. As your cholesterol is 5.8, it's important to get the LDL and HDL measured separately and only then will you know whether cholesterol reducing spreads are good enough for you. Obviously, tablets like statins will reduce LDL by 30-50% and the effect of these cholesterol lowering spreads is additive to that of statins.
From Jill Mussett: I am in my late fifties, I take regular exercise and I grow all my own vegetables organically. On a routine check up, my cholesterol was checked. My HDL is 1.8 and LDL 12.25 Longevity does not run in my family and various relatives have died relatively young.
Can diet and exercise alone bring down my cholesterol? How much at risk of coronary heart disease am I? I have been prescribed Lipitor but haven't taken them yet as I hate taking tablets and I am concerned about side effects, but I take herbal supplements. If my condition is inherited, will my adult sons be at risk are they and should they be seeking advice?
Clive Weston: These are significantly abnormal cholesterol and triglycerides results.
If this was a fasting specimen (nothing but water for 12 hours before the blood test) I would want you to have your thyroid function tested (a different blood test). If your thyroid function is normal, then there is a chance that you have an inherited disorder of fat metabolism such as familial hypercholesterolaemia.
Diet and exercise alone are unlikely to reduce your LDL to safer levels. You've been prescribed a statin which at a high dose, say 40-80 milligrams per day, should reduce your LDL to about 6-7. It may not reduce your triglycerides very much. Fish oil supplements will achieve this and you may feel more comfortable taking such supplements.
Your sons must avoid riskly behaviour like tobacco smoking and should stay as physically active as you are. They should be counselled by their GPs about having a cholesterol test and encouraged to have the test.
If a repeat blood test (in your case) continues to show such high LDL and triglycerides, I would encourage you to ask your GP for a specialist opinion. In the meantime, I would take the statin prescribed - which should not have short-term side effects.
From Kathryn: 6 months ago I was diagnosed with hypothyroidism (congenitally small-sized thyroid) and was told my elevated cholesterol was due to that. Since treatment, my cholesterol is lower but can you please tell me what is the relationship between the thyroid gland and cholesterol production?
Clive Weston: I don't fully understand the mechanism by which low levels of thyroid hormone lead to high levels of cholesterol - part of it is the weight gain, often seen as the thyroid becomes less active - part of it must relate to a change in the metabolism of fat within the body. However, your experience of improvement in cholesterol as thyroxine is taken, is common. Perhaps we as doctors should remember to check thyroid function more often in people with slightly elevated cholesterol.
From Serge Middleton: I have been on statins for years (since my thirties, am now in my fifties), I've watched the diet, and excercise daily, yet my cholesterol level is still going up. Recently the dosage was doubled, still chol. level rises, why?
Clive Weston: The "starter" dose of statins tends to reduce LDL cholesterol by 30-50% (depending on which statin you use) and your risk of heart disease by about 30% over five years.
Simply doubling the dose of a statin is usually associated with only an extra 6% reduction in LDL cholesterol so we don't see substantial benefit from doubling the dose. Some members of the statin family are more "potent" than others.
As we get older our cholesterol tends to rise, but it's difficult to tell you why your cholesterol is going up in spite of what I assume is a good diet and your daily exercise. Can I suggest:
1. Get to ideal (increasing weight increases cholesterol)
2. Make sure the increase is not simply in HDL (HDL is good)
3. Check your thyroid function, liver function (both blood tests) and don't drink too much alcohol.
All these things can lead to an increase in cholesterol.
From Mark Collyer: What is the impact of alcohol on cholesterol levels? Are any types of alcohol better than others (eg wine vs spirits)?
Clive Weston: There's no doubt that alcohol increases triglyceride levels in a dose response way (the more you drink, the higher they go). However, a small quantity of alcohol consumed each day increases HDL cholesterol (the cardio-protective type of cholesterol). This is thought to be the reason that small amounts of alcohol (two units per day) appears to have a cardio-protective effect.
Remember, there are calories in alcohol and too much alcohol leads to weight gain and the beneficial effects are reversed. If red wine is to your taste, so much the better! Interestingly, a colleague of mine is prescribing a glass of red wine to his patients within his heart unit during their stay in hospital.
From Pat Nelson: I had my cholesterol levels checked about 5 years ago, and they were over 7. My GP decided to take no further action, but since then I have lived on a low fat diet, exercised 2/3 times a week, eat sardines twice a week, rarely eat red meat, and used cholesterol reducing spreads.
I decided to repeat the test a couple of weeks ago, and the level is 6.9. My GP is suggesting a further test in 6 months. I cannot see the pupose of this, as I do not know what more I can do. I am 62 years of age. Should i just wait another 5 years?
Clive Weston:
At this stage it is important for you to know your level of HDL. Some people - women in particular - have high HDL levels (eg greater than 2) and this is the reason that their total cholesterol appears raised. In fact, all your hard work may have paid off with a high HDL - it would be good for you to find out so make sure your next test is performed on when you have been fasting for twelve hours (this makes HDL measurements meaningful). Finally, remember that the risk of heart disease with a lot of other factors and these should all be entered in the calculation of risk.
From Fred Baker: I am a 55 years old male, I had a heart attack recently and I am trying to lower my cholesterol level.
My problem is that I have had to stop taking all four medications I have tried so far because of their side effects. Either they cause leg pain (pravastatin simvastatin) or "make my brain numb", by which I mean tired, lazy, restless, unable to concentrate (fluvastatin gemfibrozil).
I would very much appreciate it if you could mention any cholesterol lowering drug(s) which might have less of this mental/brain side effect?
Clive Weston: Mr Baker, you are unfortunate in being unable to tolerate these drugs and I share your concern. Some of my colleagues believe that muscle pains associated with statins are caused by the development of a deficiency of a compound called co-enzyme Q10. Although I know of no large clinical trial investigating this, at least one consultant colleague has experience suggesting that statins can be taken with co-enzyme Q10 without such side effects - I'm afraid I can't formally endorse this strategy, but it could be worth a try.
Failing this, there is quite good evidence that fish oil in capsule form reduces the risk following a heart attack and there are other cholesterol medicines (niacin and cholesterol absorption inhibitors) that can be tried. Most importantly, whether you can tolerate tablets or not, you must do your best to have a healthy diet and exercise regime. These are equally important, as your cardiac rehabilitation team will have told you.
From Louise Shellard: some time ago my mother was prescribed Fluvastatin for cholesterol. Soon after, she developed muscle pains, and she was told that there were some problems with her liver caused by the drug, She is very distressed over possible damage to her liver and the consequences, and whether it might be permanent.
Many thanks
Clive Weston: First, the liver is the organ with the most ability to heal itself following a variety of "insults". All statins have been shown to cause increase in chemicals called liver enzymes. Such increases are usually reversible (when the statin is stopped) and don't lead to permanent damage. Because a liver function blood test was apparently not performed when the statin was started, it's difficult to be certain that the statin was to blame. Women in your mother's age group do have other causes of liver abnormality, so unless the liver function returns to normal, her doctor might have to reconsider the statin as a cause and consider doing some other tests.
The medical profession cannot agree whether regular liver function monitoring is important and I have been to meetings where senior clincians have stated that they do not measure liver function as a routine. The manufacturers still recommend that liver function should be measured and monitored and I think your mother's case justifies this policy - if only to have identified whether the liver abnormality was present before treatment started.
From Russell Martin:
I see from various sources that homocysteine is a better marker for impending heart disease. What is it, and why?
Clive Weston: Homocysteine is an amino acid derived from the diet. It's metabolism within the body requires folic acid, Vitamin B12, and Vitamin B6. It is true that the level of homocysteine does appear related to the risk of heart disease (the higher the level, the greater the risk). Interestingly, people taking higher quantities of folic acid and vitamins seem to have lower homocysteine blood levels and fewer heart attacks.
What has not been shown is that adding folic acid and vitamin supplements substantially reduces the risk in at-risk individuals. This may seem to contradict the previous sentence, but remember those who have chosen to take such vitamin supplements are also those who tend to lead healthier lives. Homocysteine has not replaced cholesterol measurement in assessing overall risk.
From Les Klieman: My wife has a total cholesterol of 5.7,HDL 1.85 & LDL 3.25 Her G.P says she doesn't need any drug treament. My question, therefore, is what are the recommended levels for the various lipides and should our G.P reconsider his advice not to prescribe cholesterol lowering drugs - say statins?
Clive Weston: I can only assume that the cholesterol profile, when added to her other risk markers (such as age, smoking, etc) put her in a group of people who wouldn't much benefit from tablet treatment, because they're not at very high risk. Her HDL is right at the upper limit of normal - that is good. Ideally it would be nice to see the LDL below 3, but in general terms I would not be very worried with this cholesterol profile (taken in isolation).
It is likely that the new targets for people who have already had a heart attack will be:
Total cholesterol: less than 5
LDL (bad) cholesterol: 2.5
HDL (good) cholesterol: above 1.0
From Paul: Is a high fat diet the same as a high cholesterol diet? And if I cut my fatty diet, will it cut my cholesterol level and my risk of heart disease?
Clive Weston: No. For example, oily fish contain particular forms of fatty acids that are not in fact cholesterol. Many of the fats we eat are absorbed in the form of triglycerides (a trio of fatty acids) - again not cholesterol. So in fact we only absorb about one gram of pure cholesterol from our diets each day. But obviously, a lot more fat.
The type of fat we eat is, I am sure, important.
Cutting down fat in your diet (particularly saturated fat) may not lead to a direct reduction in total cholesterol but, through other mechanisms, will reduce your risk of heart disease.
Barbara Myers: I think Clive has done a great job answering all these tricky questions on air as well as here on the website. So thanks very much to him and to everyone who joined us for today's programme.
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