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Q. What would be a typical, clinical scenario that someone might encounter that indicates that there is some permanent brain damage that's occurred due to alcohol?
A. It's important to understand that it's relatively subtle. We often have to send people away for quite detailed neuropsychological studies to pick this up. But the sort of thing is that they have problems solving problems, their judgement goes off so that if, for example, someone was running a business you might just see over a period of years a decline in the business just because he's not quite up to standard, not up to scratch.
Q. Is that the kind of thing that in the past was not picked up?
A. Yes. Yes, it was missed. They may have a faint problem with memory, for example, and, as I say, you need very sophisticated tests to be able to pick it up. And to monitor it over a period of time is the important thing - to see a difference between today and, say, six months or a year's time. This is the way that we're able to identify the clinical problems associated with alcohol related brain damage.
Q. How much do we know at this stage about which parts of the brain are damaged permanently?
A. We've done a lot of brain cell counts here. We've actually taken different segments from different parts of the brain and looked at the numbers of nerve cells in the grey matter or cortex. And what we found was that it seems to be the front part of the brain, the frontal lobes, but also the back part of the brain that controls balance - they're known as the cerebellum - they seem to be the two predominant areas that are affected.
Q. How extensive is the damage in those areas?
A. In the cell counts that we studied in the frontal lobe, we found approximately a 20% reduction in the numbers of nerve cells - that's in someone drinking probably 12 drinks a day or more over a period of 20 or 30 years . . . so a long drinking history.
Q. 20% . . . that's a pretty big function to knock out.
A. Yes, it's a lot of brain cells and I suppose what you have to remember is that there are many other parts of the brain that aren't as severely affected and that's why the deficits that occur, the clinical problems that occur, are subtle.
Q. In someone who's vulnerable and has been drinking for that long period and drinking really excessively, what kind of effect would you expect to see? What kind of change in their behaviour, or the way their body performs, as far as damage to the cerebellum is concerned? How would that show up?
A. The damage to the cerebellum usually manifests as loss of balance - that's the predominant thing. So you'll find someone is just not as steady on their feet. They might be staggering. The term used clinically is ataxia.
Q. How do the behavioural changes you see relate to damage to the frontal lobe? In other words, what is it that the frontal lobe does so that the damage to it causes a change of behaviour?
A. The frontal lobe of the brain controls a lot of functions, such as integration of thoughts and thought processes, problem solving - it also is an important controlling influence of emotion, but emotion doesn't seem to be impacted particularly with alcohol brain damage.
Q. But aren't there quite a few other areas that you can now pick up? Other things in the frontal lobe that are affected.
A. Yes. That's right.
Q. What would be a typical kind of scenario that a clinician might be presented with from someone who comes to them suspecting there's damage to the brain from alcohol?
A. It can be relatively subtle. I think it's important for us to realise that, first of all, not everyone is affected, but probably 50% to 60% of people who are drinking 12 drinks or more a day over a period of 10 or 20 years will be affected. And they will find, or their workmates or husbands and wives will find, that at the top of their performance, they're not quite performing as well as they used to. So if they're running a business, for example, the business will start to go into a decline. Their judgement's impaired. If they have to solve a problem they'll often find that difficult. If they're asked to learn new skills, for example learning to work a computer, they might have problems doing that. We really need to send these people along for detailed neuropsychological studies before we can actually establish that they do have alcohol-related brain damage. And the best way is to study people over a period of time so you can show a gradual decline in function over a period of, say, six months or a year.
Q. But it's the kind of thing you can actually definitely get a handle on now, it's not just, 'Oh, this is someone who's a bit run down, or a bit tired . . .'?
A. Yes. You can get a handle on it now. I think that the sophistication of neuropsychological tests is much greater now than it was 5 or 10 years ago and given a reliable clinical history of someone who's a drinker, we can make a good correlation between how much they're drinking, how long they've been drinking, and how much dysfunction they have.
Q. How extensive does the damage in the brain have to be to produce this kind of change?
A. We've looked at many cases and actually counted the numbers of nerve cells in different parts of the cerebral hemispheres of the brain, the grey matter of the brain. We've found that in certain parts of the brain, particularly the frontal lobe, there's approximately 20% loss of nerve cells in people with this long drinking history.
Q. I presume there'd be a lot of cells in there to count?
A. There are thousands of cells. We have to use an automated system where we link up a microscope to a computer so that we can measure it in this way. In fact previous studies have really been worthless because of the difficulty in cell counting.
Q. Are you saying that this will happen to anyone who drinks, say, in excess of eight drinks a day over many years?
A. You can't say that it will happen to everyone. Everyone will quote you stories of Winston Churchill who drank this much over 50 years and was still functioning as well, or better than most of us. So it doesn't happen to everyone, and the unpredictability has probably a lot to do with genetics. People are just beginning to uncover the genetic story of who's susceptible. I think in another few years we may have some predictability from genetic studies in alcoholism.
Q. Is all the damage in the brain irreversible?
A. There are reversible and irreversible components of the brain damage. If the nerve cells are lost, they cannot be recovered - so that's an irreversible change. On the other hand, the nerve cells have a very intricate network which allows them to communicate with each other, a bit like a ? trigger, a system of roots. We find with alcohol that this root system retracts, and that's a reversible change. If you look at an experimental animal taken off the alcohol it's been drinking, these roots grow again. On the other hand, we also suspect a reversible component in the main long connections, which form the white matter of the brain. This [white matter] is also reduced in alcoholics and we suspect from looking at x-ray studies of people who are alive, if you study them over a period of time during which they haven't been drinking, there's a re-expansion of the white matter, which we suspect is also a partly reversible change.
Q. That's quite amazing, because we're so used to hearing that the brain, once damaged, cannot recover.
A. Yes. It's a very important message to get through to the general public. This is because there's always been a sense that alcohol kills so many thousand brain [cells?] . . . every time you go on a binge this is irreversible . . . so what's the point of stopping? I think it is important to get the message through that there is a reversible component of brain damage in alcohol related problems.
Q. Whereabouts in all of this does the thiamine story fit in? Can you explain a little bit about the influence of alcohol on thiamine in the body?
A. Yes. The thiamine and alcohol story is that vitamin B1, or thiamine, is absolutely essential to our maintenance of our body systems and is very important for the brain. We only have about three weeks of stores of thiamine in our body so it's very easy to become deficient. Alcohol itself reduces the absorption of thiamine from the body. It impairs storage of thiamine in the liver. It impairs the function of thiamine in the brain. So there's a very close interrelationship between thiamine and alcohol. Australia probably has the highest level in the world of thiamine-deficient brain damage - something like two to three per cent (from autopsy studies) of people have this brain damage and it's a devastating brain damage - they lose their memories completely. So they really can't function in life. The exciting thing is that the Government finally realised that this was an important nutritional problem in Australia, so thiamine was added to flour, and of course to bread and so on, back in 1991. We hope that this is going to have an impact on reducing the problems of alcohol-related thiamine deficiency.
Q. Isn't this also pointing to the need for people to have a healthy diet if they're going to drink?
A. Yes. A healthy diet is absolutely essential in minimising thiamine deficiency in alcoholics.
Q. Do we have any clue yet as to whether the addition of thiamine to flour has had any effect on the national average - whether it's taken us out of the Guinness Book of Records?
A. We're currently doing a study, which will take us about 18 months, to estimate the prevalence of the disease caused by thiamine deficiency. We should have an answer by the middle of next year. It will be very interesting to see if this public health measure has been as effective as we hope it will be.
