Monday, December 03, 2007

Scientists believe they can reverse dementia

AUSTRALIAN scientists believe they have cracked the code to preventing dementia by restoring the decaying brain cells of a 65-year-old to the levels of an 18-year-old. The research, presented to pharmaceutical chiefs at a closed event last week, offers new hope for the 200,000 Australians suffering dementia - a group of degenerative brain disorders that includes Alzheimer's disease.

The scientists have developed two ways to stimulate stem cells and regenerate the brain, boosting mental functions such as understanding and memory. Leading stem cell scientist Dr Rod Rietze and his team at the University of Queensland believe increasing the number of stem cells in young and middle-aged brains will help stave off dementia. "The idea is not to transplant anything - but to stimulate what we have got," Dr Rietze said. "The job of the stem cell is to do two things: keep the body functioning and regenerate the tissue. "It makes sense that if you increase the regenerative cells, the brain lasts longer."

Dementia is a major health burden, costing more than $1.4 billion per year - a figure that is expected to blow out due to a rapidly ageing population and longer life expectancies. As people get older, the number of stem cells in the brain decreases rapidly and brain function deteriorates.

Dr Rietze's first approach to turning back the ageing clock involves injecting growth hormones directly into the brains of mice. The second approach involves using physical exercise on a treadmill to trigger stem cells to multiply naturally and improve brain function. "When people do regular exercise, they age better," Dr Rietze said. "There is a correlative relationship."

Dr Rietze and his team believe sustained physical activity may prevent or delay the onset of age-related dementia as much as injecting growth hormones, restoring stem cell levels of a 65-year-old back to that of an 18-year-old. The scientist, who funded his team's radical research with a $1 million Pfizer Fellowship he won in 2004, has submitted his work to international medical journals. "I think really the next step is to design treatment strategies, and the prevention of diseases," he said.


Sticking a needle in alternative medicine

Exotic therapies such as acupuncture might make people feel good. But the role of medicine is to cure patients' illnesses, not make them happy

Alternative medicine is clearly popular (1). In 1990, 60million Americans spent an estimated $13.7 billion on alternative medicine. Americans visited alternative practitioners 425million times in 1990, more often than they visited their primary care physicians. By 1996 Americans were spending $21 billion on alternative medicine. Surveys in the UK reveal annual expenditure of around œ1.5 billion on alternative medicine. And alternative practices now find themselves nestled alongside the mainstream with the best hospitals providing aromatherapy, homeopathy, reflexology, acupuncture and so forth as adjuncts or alternatives to medicines that have been developed in laboratories and tested in clinical trials.

It is important to realise that the current vogue for alternative medicine is not really about alternative medicine at all - it is about us. The whole point of alternative medicine is that it doesn't change; the techniques of alternative medicine were developed several thousand years ago and you are meant to stick with the procedure as a fixed entity. Relative to scientific medicine, which is constantly attacked by scepticism and the proposal of newer and better procedures, alternative medicine is a closed shop. Alternative procedures are what they are and they are not open to development and change: they work because they work, end of story. So if alternative medicine is becoming more popular, then it is clearly not because of any changes in the practice of alternative medicine; it is because of changes in us.

Three things have changed. Firstly, we are physically much healthier. In all corners of the world, except in the former Soviet Union, life expectancy is rising and people are physically healthier for longer stretches of time during their lives. Many factors have contributed to this happy state of affairs, including improved living and working conditions and the rise of scientific medicine that has yielded vaccination programmes, antibiotics, steroids, radiotherapy, anti-viral medicines, and so on (2).

Secondly, and relatedly, having resolved many serious illnesses that blighted lives right up to the middle of the last century, scientific medicine is bumping up against harder problems associated with mechanical wear and tear, ageing and the existential distress of living in `a world without meaning' (3). Although physical health and longevity both trend in a positive direction, there has been a swathe of new problems that are defined by the subjective report of symptoms rather than the objective signs of disease or damage (4). These are disorders such as non-specific low back pain, fibromyalgia or chronic fatigue syndrome - illnesses of the `worried well', or, more precisely, the `worried sick', encouraged by a combination of people being healthy enough to be concerned about symptoms that are unlikely to indicate ill-health and being constantly bombarded with messages about ill-health. It is a rare individual who is unaware of the apparent need to reduce caloric intake, watch their units of alcohol, stay out of the sun, eat five fruit and veg a day, exercise, self examine and heed the occasional twinge as a potential harbinger of disease and death (5). When the banalities of everyday life - eating, drinking, catching the occasional ray of sunshine - are perceived as potential threats to continued life, it is little wonder that people are worried and flock to their GP to parade symptoms without illness.

Thirdly, medicine can be horribly impersonal. Doctors are not much interested in your existential concerns. In fact, your doctor is probably pretty keen to look straight through you to find the disease process lurking below. Of course you are more than your illness and a good doctor will at least attempt to engage you as he or she seeks the source of your sickness. In something like Britain's National Health Service system, however, which is driven by political and economic targets, the good doctor has no time to see you and barely has enough time to see your illness. It's much nicer to see an alternative practitioner who takes the time to get to know you, and prepare a treatment that is apparently tailored just for the kind of person you are and the illness or problem you are carrying.

It is tempting to try to deal with the advance of alternative medicine by carrying out randomised controlled trials of the alternative medicine versus a placebo and/or the conventional medical technique. The Guardian`s `Bad Science' columnist, Ben Goldacre, and other contemporary critics of alternative medicines see much benefit in controlled trials to expose the falsehoods of alternative medicine quackery (6). An excellent example of this approach was recently reported by Haake and colleagues (7). They investigated two types of acupuncture versus conventional therapy for chronic low back pain. The first type of acupuncture was based on traditional Chinese meridians; the acupuncture needles were inserted into appropriate Chinese acupuncture spots. The second type of acupuncture followed the same procedure but the needles were inserted into non-traditional or sham spots. Both these types of acupuncture worked better than conventional therapy, but traditional acupuncture spots did not produce better results than the sham spots. Thus it was concluded that acupuncture needles can be useful to alleviate chronic low back pain but it doesn't matter where you stick the needles. This finding echoes those of previous studies, including the finding that a cocktail stick is as beneficial as an acupuncture needle (8).

There is a reason why noxious stimulation of the skin might alleviate chronic low back pain and other types of pain. The experience of pain is never the simple and direct response to a noxious stimulus and is always the consequence of a balance of peripheral activity with activity in the spinal cord and brain that can increase or decrease the experience of pain. Whenever you hurt yourself and rub the injured region you are affecting that balance to damp the flow of noxious information and create pain relief. Noxious stimuli can also affect that balance, and that is, in essence, what the acupuncture needles do. Precisely how one noxious stimulus affects another is very poorly understood. But what we do know suggests that acupuncture shouldn't really work as well as it did in the Haake study. Rubbing an injured area generally provides only mild short-term relief, and rubbing is not likely to replace more conventional analgesics and anaesthetics any time soon.

Why, then, did the acupuncture prove to be more effective than the conventional treatments for chronic low back pain? One possibility is that acupuncture is just better. We might not understand exactly how it works, but perhaps it does work. However, there are some very good reasons to be highly dubious of this interpretation.

Chronic low back pain is a tricky disorder. More than 70 per cent of all cases of low back pain have no identifiable causal pathology. We don't know why the patients have pain and any diagnosis is based on the report of pain rather than on the observation of damage or disease. These types of pain are increasing at a ferocious rate and it seems unlikely that medical factors alone can adequately explain the large uptake in associated work-related incapacity benefits in most countries since the 1970s (4). Expenditure on these benefits has tripled over the past 30 years despite improvements in life expectancy and morbidity rates over the same period. Currently, in the UK, 70 per cent of recipients of incapacity benefit have health-related problems that are not sufficient to fully explain their incapacity in purely medical terms. In sum, chronic low back pain is more of a psychosocial than a medical problem, and so is unlikely to yield to mainstream medical intervention.

Little wonder, then, that the conventional therapy that was compared with acupuncture was a highly eclectic mix of interventions: `The therapies given in the conventional group were physiotherapy, massage, heat therapy, electrotherapy, back school, injections and guidance. In a few patients, therapies included infusions, yoga, hydrojet treatment and swimming.'

My interpretation of this study, therefore, is that at the current moment in time, patients with a non-specific existential disease prefer to spend time with an acupuncturist than with a heat therapist, and it is no surprise that patients report feeling better when they do things that they prefer to do. But it is not the role of medicine to run randomised control trials of stuff that makes people happy in order to prove that stuff that makes people happy tends to make them feel happy. While randomised controlled trials can be justified in some cases, we should not view them as blanket solutions to the problem posed by alternative medicine. Such trials are extremely time-consuming and expensive, and it is often not worth the time and expense to investigate something that is obviously unfounded. Moreover, conducting such a trial can give the impression that a treatment must be worthwhile, given all the expense and time being invested. A negative finding will not necessarily forestall the advocates of alternative medicine and a comprehensively negative finding is always difficult to achieve. Positive effects can be discovered for all sorts of non-specific reasons that can never be fully explained away even if they are almost certainly spurious.

It is also important that medicine does not get too flippant and include alternative treatments because of the argument that they `seem to work' and they `can't do any harm'. First of all, to the extent that these treatments work it is probably via non-specific psychological mechanisms that are parasitical upon prior experiences with medicines that do work. It would be cynical to deliberately mobilise those non-specific responses to provide benefit from a known ineffective treatment. If medicine becomes less than serious about promoting interventions that are known to work via well-understood and well-studied mechanisms, then the authority of medicine is put at risk and the benefits of non-specific psychological responses to medicine may soon be lost.

Secondly, there is the possibility of harm even if the intervention is seemingly innocuous. Most obviously there is the danger of over-zealous advocates of alternative medicine promoting homeopathy to cure cancer, malaria or AIDS and so forth. Less obviously there is the potential undermining of straightforward, bland, but effective medical advice (6). Recently, Hancock and colleagues reported that those presenting with an acute onset of back pain are best treated with advice to stay active and take paracetamol if needed (9). The addition of spinal manipulation or spinal mobilisation and further medication did not provide for a better outcome.

Time is a great healer and most acute symptoms will resolve quite naturally (10). Alternative medicine is partly promoted using the poisonous idea that doctors providing short and simple interventions are fobbing their patients off and not showing the required concern. This encourages patients to focus on their symptoms of ill-health unnecessarily and consume medicines or partake in activities that are unnecessary, unwise or dangerous. This is quite simply an unhealthy state of affairs that actively encourages people to be sicker than they need to be or otherwise would be. In short, medicine needs to recognise that alternative medicine is part of the problem, not part of the cure.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correla-tion coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic condi-tions and lynchings in Raper's data. Raper had the misfortune of stopping his anal-ysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


1 comment:

Kathy NC said...

My name is Kathy, and I am the primary caregiver for my 79 year old Dad who has Alzheimer's disease and lives with me in North Carolina.

I am writing a daily blog on my Alzheimer's caregiver website that shows the lighter side of caring for someone with dementia.

Please pass this link along to anyone you feel would enjoy it.