Sunday, April 01, 2007

Kill that Alzheimer!

Or so the policy looks in Britain

Drugs commonly prescribed to people with Alzheimer’s disease are accelerating their deaths by an average of six months, a study has found. Up to 45 per cent of people with Alzheimer’s in nursing homes are given sedative drugs known as neuroleptics to try to control behavioural symptoms such as aggression. In severe cases, the drugs may be justified. But a five-year study by the Alzheimer’s Research Trust showed that, as well as reducing life expectancy, they were of no benefit to patients with mild symptoms and were associated with significant deterioration in verbal fluency and cognitive function.

Clive Ballard, professor of age-related disorders at King’s College London, who presented the findings at the charity’s conference in Edinburgh yesterday, said: “It is very clear that even over a six-month period of treatment there is no benefit of neuroleptics in treating the behaviour in people with Alzheimer’s disease when the symptoms are mild. “For people with more severe behavioural symptoms, balancing the potential benefits against increased mortality and other adverse events is more difficult, but this study provides an important evidence base to inform this decision-making process.”

Rebecca Wood, chief executive of the Alzheimer’s Research Trust, said: “These results are deeply troubling and highlight the urgent need to develop better treatments. “Seven hundred thousand people are affected by dementia in the UK, a figure that will double in the next 30 years. The Government needs to make Alzheimer’s research funding a priority. Only 11 pound is spent on UK research into Alzheimer’s for every person affected by the disease, compared with 289 for cancer patients.”

The study examined 165 people with Alzheimer’s living in nursing homes in Oxford-shire, Newcastle upon Tyne, Edinburgh and London. They had been taking neuroleptic drugs for at least three months and took part in a trial in which some were taken off the drugs and others were not. The drugs involved were thioridazine (Melleril), chlorpromazine (Largactil), haloperidol (Serenace), trifluoperazine (Stelazine) and risperidone (Risperdal). Follow-ups in succeeding years showed striking differences in survival. After two years survival was 78 per cent in those taken off the drugs, and 55 per cent in those still on them. After three years the figures were 62 per cent against 35 per cent, and at 42 months 60 per cent against 25 per cent.

Neil Hunt, chief executive of the Alzheimer’s Society , said: “Neuroleptics have been used as a dangerous fix for ‘challenging behaviour’ in people with dementia for too long. “These drugs have now been exposed as having no benefit for people with dementia, while causing a dramatic increase in the risk of death. It is a disturbing revelation that confirms some of our worst fears about neuroleptics, which have been the subject of numerous health warnings. “It is a national scandal that people are being sedated in this way. These drugs must be a last resort only used when all other methods have failed to alleviate the most distressing symptoms of dementia.”


More vaccination needed?

Waning immunity after childhood vaccinations has prompted concerns we may need to better protect adults from disease. The report below is from Australia but the implications apply anywhere

When you think chickenpox, do you imagine spotty but otherwise happy kids quarantined at home and amused with colouring books and hot drinks? If so, you may be surprised to learn that pneumonia, inflammation of the heart muscle and swelling of the brain (encephalitis) are all potential complications of this highly contagious disease, which causes 1500 hospitalisations and seven deaths in Australia each year.

Although it's a mostly mild illness in children, chickenpox - caused by the varicella zoster virus, one of the herpes family - can be nasty in adults, particularly the elderly, pregnant women, and other people with compromised immune systems. Since November 2005 a federal Government funded vaccine for varicella has been available free to all children aged 18 months (and at 10-13 years for non-immune children who haven't already been immunised). The problem is, no one is quite sure how long this protection lasts - estimates range from 10 to 20 years, or longer. It's a question that has significant implications as people age and become more susceptible to disease.

An editorial in the respected New England Journal of Medicine (2005;352(22):2344-6) suggested that mass childhood vaccination against chickenpox might ironically be leaving some people more vulnerable to the adult disease, which it said was "far more serious than childhood varicella usually is". And experts are also raising questions about waning post-vaccine immunity to other diseases. Not all vaccines offer lifelong protection and many of the newer ones have just not been around long enough for us to know how effective they are long-term. We know for example that immunity following a vaccination for pertussis - whooping cough - usually lasts only around five to 10 years.

Recently-released draft Australian immunisation guidelines are already suggesting that, contrary to current practice, children might need a second dose of chickenpox vaccine before 13 years of age, and receive their first dose six months earlier, to give them earlier and more sustained protection. "Waning immunity is often under-recognised," says Peter Eizenberg, a Melbourne GP who sits on several national immunisation committees. "It is an important issue in the community, particularly among the elderly, but not just the elderly. People get vaccinated and they forget that only a few of the vaccines give long-term immunity."

The NEJM recently revisited the topic, suggesting again that varicella vaccination could lead to a shift in the disease burden to older people (2007;356:1121-9). "Waning of immunity is of particular public health interest because it may result in increased susceptibility later in life, when the risk of severe complications may be greater than in childhood," the authors say.

Professor Lyn Gilbert, director of the Centre for Infectious Diseases and Microbiology at Westmead Hospital's Institute of Clinical Pathology and Medical Research, says the combination of mass childhood vaccination and waning immunity might see an increase in cases of shingles - a painful condition caused by the re-activation of the varicella zoster virus, which continues to lurk in nerve cells after a childhood infection. Shingles has its own set of complications. It can sometimes cause permanent, painful nerve damage and can actually transmit the chickenpox virus itself to people who aren't immune. "Shingles . . . is potentially a time bomb waiting to happen," Gilbert says.

The theory is that because mass childhood vaccination greatly reduces the amount of "wild" virus circulating in the community, it means that people's immunity to varicella is no longer being constantly "topped up" by re-exposure to it. "There is a very plausible model that suggests that if you reduce the incidence of infection in children through mass vaccination and older people are not exposed to wild virus, they are likely to have reactivations," Gilbert says. For the elderly, there may be hope of protection with a new shingles vaccine manufactured by drug giant Merck. Zostavax was licensed by the US Food and Drug Administration last year for use in people over 60. It's not yet available in Australia, but there are hopes that it soon will be.

Director of the National Centre for Immunisation Research and Surveillance professor Peter McIntyre says the vaccine would initially be used in the over-60s, but may in future be used for younger patients. Gilbert says in the long term, those vaccinated for varicella in childhood will probably require boosters as they age. But she says uncertainties over whether boosters are needed or not tend to muddy the waters on the true costs of a government funding of vaccines.

And funding of new vaccines doesn't come cheap. In the last financial year, the federal Government spent about $250 million on vaccines. Cabinet this week agreed to spend $124.4 million over five years to immunise babies against rotavirus, which hospitalises 10,000 children a year. Estimates are that this could save the health system some $30 million annually by preventing illnesses.

One disease where waning immunity issues pose a significant challenge is the highly infectious whooping cough (or pertussis), which is on the rise worldwide. It is less dangerous to adults than it is to young babies, for whom it can cause brain damage and even prove fatal. Adults can develop hernias and rib fractures from the coughing, but a particular problem in adults is that it might not be recognised as pertussis at all - missing an opportunity to limit transmission. Most babies are immunised against pertussis, but protection is not achieved until after the third dose at six months of age, so waning immunity to the vaccine and resulting infection in adults is putting these children at risk. "Pertussis is a number one problem," Eizenberg says. "It is in epidemic proportions . . . we have around 10,000 cases a year notified to the department of health and that probably under-represents the true numbers by 3-4 times because mild cases can be hard to diagnose but remain very infectious."

There's still uncertainty over how many pertussis boosters are needed, because the adult booster, called Boostrix, is only relatively new. While the federal Government funds Boostrix for 15 to 17-year-olds, there is no public funding for pertussis vaccination of older adults. Eizenberg would like to see national, publicly-funded routine immunisation with the combined diphtheria/tetanus/pertussis vaccine for all eligible 50-year-olds. The Australian Technical Advisory Group on Immunisation (ATAGI), which advises the federal government, is looking at whether there is a case to recommend a routine pertussis booster in middle age, a decision that would be a world first. "The unknown question is, how long will the vaccine last?" says ATAGI chairman professor Terry Nolan. "There is a possibility that progressive boosting will be needed to protect throughout life."

Another problem is measles, which in the 24 years from 1976 to 2000 caused nearly 100 deaths in Australia. While this figure is small, experts are still concerned. Small outbreaks continue to occur around the country and immunisation levels aren't as high as they could be, particularly in young adults who may not have been fully vaccinated in childhood. As for how long vaccine protection lasts, it has been thought that immunity was long term. But some experts believe that waning vaccine-induced immunity could become an issue. Introduced measles is a particular threat - from Australians who travel overseas."A classic situation is an unimmunised young Australian male, goes to Bali, picks it up there and comes back and infects all his mates," Gilbert says.

Experts say funding issues do make a difference to vaccine uptake and the battle to maintain levels of disease protection. "I think there is a culture amongst a lot of people that if a vaccine is not 'free' then it can't be important," Eizenberg says. This sort of attitude can make it hard for GPs to convince people who don't feel sick that they need a booster jab. McIntyre says although diphtheria/tetanus or diphtheria/tetanus/pertussis is recommended at age 50 (but not publicly funded), "the chances are most people don't do it". "We think most people don't get around to it and doctors forget to remind people and it's not free." Eizenberg says a national adult immunisation register could keep track of all vaccinations and trigger reminders.

It seems the Federal Government agrees in principle. In the last budget it allocated $1.2 million to explore redeveloping the Australian Childhood Immunisation Register into a whole-of-life register that included adult immunisation. Health Minister Tony Abbott is due to see a report on the concept some time this year. According to Gilbert, adult immunisation is becoming much more of an issue. "Increasingly, people are beginning to recognise better the burden of illness in older peo ple." But difficulties in reaching younger adults and unanswered questions about waning immunity means the cost-effectiveness of paying for immunisation programs from the public purse might be doubtful. It seems a big question for the future is, to whom should we give boosters, and can we afford it?



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].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.