Tuesday, November 20, 2007

Thousands dying ‘because simple screening system has been delayed’

Delays in introducing a screening programme for a deadly blood condition are costing the lives of thousands of men each year, doctors say. Aortic aneurysms — swellings in the main artery of the stomach — can kill without warning and are the third most common cause of death for older men. But the Government has failed to bring in a national screening programme nearly two years after it was urged to do so.

All four UK health departments are considering whether all men in their mid-sixties should be screened for an abdominal aortic aneurysm (AAA), which is found in up to one in ten men aged 65 to 79. About 7,000 men bleed to death every year because of the condition, even though it can be prevented by a simple operation.

Campaigners say that checking whether men are at risk of a ruptured aneurysm would cost 25 million pounds, half the price of the breast cancer screening programme, and would save as many lives — at least 3,000 a year. The UK National Screening Committee recommended the programme in January last year and sketched out how it would work in May this year.

The abdominal aorta carries blood to the intestines and other organs nearby. Aneurysms, in which the arteries weaken, stretch and bulge, are common in this part of the body. Ruptured aneurysms are catastrophic: more than 85 per cent of men die when an unsuspected aneurysm bursts, compared with only 5 per cent of those who have a planned operation. However, those at risk can be assessed by a simple ultrasound scan.

George Hamilton, president of the Vascular Society of Great Britain and Ireland, accused ministers of unnecessary delays in implementing a full screening programme. “Ruptured aneurysm is a common and painful way to die. The evidence in support of screening is incontrovertible,” he said. The test, which involves measuring the diameter of the aorta, is funded in only a few areas, such as Gloucestershire, where a screening programme has been running since 1990. Yet doctors who offer screening to patients privately have been frustrated by criticisms that they are illegally charging for the service. Brian Heather, a vascular surgeon who pioneered screening for AAA cases at the Gloucestershire Royal Hospital, said that the test could be performed with a briefcase-sized portable ultrasound machine.

Factors that can contribute to the likelihood of developing an aneurysm include family history and risk factors for heart disease such as smoking, obesity and high blood pressure.

Derek Kendall-Smith, 77, a former England rugby international and managing director of a jewellery firm, had surgery for an aneurysm two years ago. He said that a 95 pound voluntary test had saved his life. “If I hadn’t been screened I would have had no idea there was ever a problem,” Mr Kendall-Smith, of Marlow Bottom, Buckinghamshire, said.

A Department of Health spokesman said: “This assessment has to take account of the likely impact on existing healthcare services and the infrastructure and staffing requirements.” [Translation: It would cost too much]



A gene that contributes to obesity has been identified for the first time, promising to explain why some people easily put on weight while others with similar lifestyles stay slim. People who inherit one version of the FTO gene rather than another are 70 per cent more likely to be obese, British scientists have discovered. One in six people have the most vulnerable genetic makeup and weigh an average of 3kg more than those with the lowest risk. They also have 15 per cent more body fat.

The findings provide the first robust link between any common gene and obesity, and could eventually lead to new ways of tackling one of the most significant causes of ill health in developed countries such as the UK. One in four British adults is now classified as obese, and half of men and a third of women are overweight. Obesity is a major cause of heart disease, cancer and type-2 diabetes, and an adviser to the Government's health spending watchdog described it recently as a bigger national hazard than smoking, alcohol or poverty. If the biological function of the FTO gene can now be understood, it could become possible to design drugs that manipulate it to help people to control their weight.

"Even though we have yet to fully understand the role played by the FTO gene in obesity, our findings are a source of great excitement," said Professor Mark McCarthy of the University of Oxford, who led the research. "By identifying this genetic link, it should be possible to improve our understanding of why some people are more obese, with all the associated implications such as increased risk of diabetes and heart disease. New scientific insights will hopefully pave the way for us to explore novel ways of treating this condition."

While it has long been understood from family studies that obesity is heavily influenced by genetics, scientists have struggled to pin down individual genes that are involved. A handful of serious genetic mutations that cause rare obesity disorders such as Prader-Willi syndrome have been found, but the search for common genes that affect ordinary people's risk of becoming obese or overweight has remained elusive.

The effect of FTO emerged from a major study of the genetic origins of disease funded by the Wellcome Trust known as the Case Control Consortium, in which 2,000 people with type-2 diabetes had their genomes compared to 3,000 healthy controls. Scientists from Oxford and the University of Exeter first found that certain versions of the FTO gene were more common among people with type-2 diabetes, but that the effect disappeared when the data were adjusted for obesity. This led them to wonder whether FTO actually influenced obesity instead, and they followed up their theory in a further 37,000 people.

FTO comes in two varieties or "alleles", and everyone inherits two copies of the gene, one from each parent. The team found that people who inherit two copies of one variant - 16 per cent of white Europeans - were 70 per cent more likely to be obese than those who inherited two copies of the other allele. The 50 per cent of subjects who inherited one copy of each FTO variant had a 30 per cent higher risk of obesity. Those in the highest risk group weighed an average of 3kg more and those at medium risk were an average of 1.2kg heavier. In each case, the extra weight was entirely accounted for by more body fat, not greater muscle or extra height. The results, which are published in the journal Science apply to both men and women, and to children as young as seven.

FTO will not be the only gene that influences obesity, and inheriting a particular variant will not necessarily make anyone fat. "There are going to be lots of slim people with two copies of the bad allele, and if people who have the more favourable version overeat or don't exercise they are still going to become obese," Professor McCarthy said. "This is not a gene for obesity, it is a gene that contributes to risk." The biological function of FTO remains unknown, and the scientists now plan to study this by creating genetically modified mice in which the gene is knocked out.

Professor McCarthy said the gene is highly active in the hypothalamus, a part of the brain involved in appetite control, suggesting that one potential way it might have its effect. The gene could also influence how readily fat cells are laid down.

The research involved too many people to control for exercise and diet, so it is not yet known whether FTO affects how much people eat or how active they are. Andrew Hattersley, who headed the Exeter group, said it might nevertheless explain how people with apparently similar lifestyles differ in their propensity to put on weight. "Our findings suggest a possible answer to someone who might ask: `I eat the same and do as much exercise as my friend next door, so why am I fatter?'" he said. "There is clearly a component to obesity that is genetic."

Professor McCarthy played down the idea of screening people for FTO, so they can change their diet or exercise habits if they are found to be at higher risk. "We are not pushing genetic testing here. A 3kg increase is significant, but it is not 30kg, and there are always going to be other genes and environmental factors involved. The best way of predicting who is becoming obese is to weigh them."

Independent obesity experts said the discovery was highly significant. Susan Jebb of the MRC Human Nutrition Unit said: "This research provides clear evidence of a biological mechanism which makes some people more susceptible to gaining weight in a world where food is plentiful and sedentary lifestyles the norm. By studying the action of this gene we may learn more about the detailed causes of obesity."

Professor Steve O'Rahilly of Cambridge said: "It is unlikely to be the only such genetic variant, but it is the first to be discovered. Unfortunately we have no idea what this gene actually does to alter our degree of fatness. It is made in every cell in the body and doesn't look like any genes whose functions we understand so we have very few clues as to how it might affect a person's risk of obesity. This is a very exciting first step but there is much work still to do."


British Doctors' revolt at anti-white bias

ONE of Britain's most eminent consultants has claimed white male doctors are being denied bonuses because of politically correct "reverse discrimination" by the National Health Service. David Rosin, a former vice-president of the Royal College of Surgeons, says female and ethnic minority consultants are being given preferential treatment to meet artificial quotas.

Rosin, also a former president of the Association for Cancer Surgery, failed to get the top "platinum award" award 10 years in a row despite being backed in his application by the royal college and his NHS trust. He said: "When I asked a previous president [of the Royal College of Surgeons] why I had been unsuccessful, the answer came back immediately: `What do you expect? You are not black, you are not female and you have all four limbs.' "

Rosin's comments are likely to provoke a row about whether policies to promote equal opportunities in the NHS have led to positive discrimination. Figures show a dramatic increase in the number of women and ethnic minorities winning merit awards over the past five years. They can add up to 73,000 pounds to a consultant's annual salary of about 112,000.

Ministers and NHS chiefs have been encouraging more women and ethnic minorities to apply. Supporters say that in the past the vast majority of the extra payments went to an "old boys' network" of sometimes "mediocre" white male consultants. However, Rosin, who retired from his NHS post as a senior consultant surgeon at St Mary's NHS Trust hospital, London, in June, believes it has now tipped into positive discrimination. "It is time that someone spoke up concerning the reverse discrimination with respect to merit awards," he wrote in a letter to the magazine Hospital Doctor. "In the politically correct environment in which we live, there is now definitely reverse discrimination."

He was incredulous at his failure to get a platinum award, despite being editor of an international medical journal, editing 16 textbooks and publishing more than 100 peer-reviewed medical papers. He said he was also on call for the NHS every second night for his first 14 years as a consultant and helped to introduce a new form of cancer surgery clinic and many new minimal access surgical techniques.

Rosin was supported by a council member of one of the royal medical colleges, who, asking to remain anonymous, said: "As in any situation where people are trying to correct what is perceived as a wrong in the past, an element of bias will be introduced. The feedback one hears from these committees is that, where there is a fine balance between two candidates, then there will be a willingness to recognise the merits of someone who has been previously disadvantaged."

About half of Britain's 33,000 consultants receive an award at some level, ranging from œ2,850 to œ73,158. The scheme costs the NHS at least 250m pounds a year.

Aneez Esmail, professor of general practice at Manchester University, whose research in 1998 showed how few women and ethnic minority consultants got the awards, denied that standards had been compromised. "More women and ethnic minorities are successful but the actual standards are not compromised," he said. "Previously, mediocre white candidates were getting awards and you really had to be quite exceptional as a woman or ethnic minority to get an award. With more transparency and clear criteria there is greater competition and more women and ethnic minorities are successful. People like Mr Rosin may lose out."

His 1998 research, published in the British Medical Journal, showed that white consultants were given 95% of bonuses despite making up just 74% of the eligible consultant workforce. Nonwhite consultants earned just 5% of bonuses despite making up 14% of the eligible consultant workforce.

A follow-up paper in 2000-2001 found that white consultants received 37% more bonuses than nonwhite consultants and men gained 25% more bonuses than women. However, this year's data, released by the health department, show that the percentage of women applicants succeeding in getting bronze awards, worth about 34,000 on top of their annual salary, is now equal to that of men.

Doctors would not be expected to apply for the four top awards until they had been consultants for a decade. Women taking breaks to have children have therefore been less likely to apply. As many British Indian consultants as white British consultants are also now being awarded the first level of bonus, worth 2,850.

Professor Hamid Ghodse, medical director of the committee which decides on who gets awards, acknowledged that it had actively been trying to get more women and ethnic minority consultants to apply for bonuses - and would continue to do so.


Sun and global warming: A cosmic connection?

By Richard Black, Environment correspondent, BBC News

The article below does give a good airing to the case for a solar influence on terrestrial warming but it of course slants its coverage toward the conventional view. Two rather amusing features are that Lockwood refuses to offer a refutation of Svensmark on the exceedingly flimsy ground that he does not like where Svensmark has posted his paper! If he DID have any answers, he would be keen to offer them. The second amusing thing is that the BBC author says that the acid test will be what the planet does henceforth. Will it continue warming or not? That it has ALREADY stopped warming (since 1998) is conveniently not taken into account

In February 2007, depending on what newspaper you read, you might have seen an article detailing a "controversial new theory" of global warming. The idea was that variations in cosmic rays penetrating the Earth's atmosphere would change the amount of cloud cover, in turn changing our planet's reflectivity, and so the temperature at its surface. This, it was said, could be the reason why temperatures have been seen to be varying so much over the Earth's history, and why they are rising now.

The theory was detailed in a book, The Chilling Stars, written by Danish scientist Henrik Svensmark and British science writer Nigel Calder, which appeared on the shelves a week after the Intergovernmental Panel on Climate Change (IPCC) had published its landmark report concluding it was more than 90% likely that humankind's emissions of greenhouse gases were warming the planet.

In truth, the theory was not new; Dr Svensmark's team had proposed it a decade earlier, while the idea of a cosmic ray influence on weather dates back to 1959 and US researcher Edward Ney. The bigger question is whether it amounts to a theory of global warming at all.

Over the course of the Earth's history, the main factor driving changes in its climate has been that the amount of energy from the Sun varies, either because of wobbles in the Earth's orbit or because the Sun's power output changes. Most noticeably, it changes with the 11-year solar cycle, first identified in the mid-1800s by astronomers who noticed periodic variations in the number of sunspots. If it varied enough, it could change the Earth's surface temperature markedly. So is it?

"Across the solar cycle, the Sun's energy output varies only by about 0.1%," says Sami Solanki from the Max-Planck Institute for Solar System Research in Germany. "When you look across much longer timescales, you also see changes only of about 0.1%. So just considering directly variations in energy coming from the Sun, this is not enough to explain the climatic changes we have seen and are seeing now."

This is why scientists have been investigating mechanisms which could amplify the changes in solar output, scaling up the 0.1% variation into an effect that could explain the temperature rise of almost half a degree Celsius that we have seen at the Earth's surface in just the last few decades.

One is Joanna Haigh from Imperial College, London, UK. She realised that although the Sun's overall energy output changes by 0.1%, it changes much more in the ultraviolet part of the spectrum. "The changes in the UV are much larger, between 1% and 10%," she says. "And that primarily has an impact in the stratosphere (the upper atmosphere) - UV is absorbed by ozone in the stratosphere and also produces ozone, and this warms the air."

Using computer models of climate, Dr Haigh's team showed that warming in the stratosphere could change the way energy is distributed across the troposphere, the lower atmosphere, changing wind and weather patterns. But not by much. "We found it might raise temperatures by a maximum of half to one Celsius in certain regions," she says. "But in terms of an impact on the global average temperature, it's small, maybe about 0.2C." Which is not enough to explain the warming that has occurred since the late 1970s.

Henrik Svensmark and his collaborators at the Danish National Space Center (DNSC) believe the missing link between small solar variations and large temperature changes on Earth are cosmic rays. "I think the Sun is the major driver of climate change," he says, "and the reason I'm saying that is that if you look at historical temperature data and then solar activity and cosmic ray activity, it actually fits very beautifully.

"If CO2 is a very important climate driver then you would expect to see its effect on all timescales; and for example when you look at the last 500 million years, or the last 10,000 years, the correlation between changes in CO2 and climate are very poor."

When hugely energetic galactic cosmic rays - actually particles - crash into the top of the atmosphere, they set in train a sequence of events which leads to the production of ions in the lower atmosphere. The theory is that this encourages the growth of tiny aerosol particles around which water vapour can condense, eventually aiding the formation of clouds.

And the link to the Sun? It is because cosmic rays are partially deflected by the solar wind, the stream of charged particles rushing away from the Sun, and the magnetic field it carries. A weaker solar wind means more cosmic rays penetrating the atmosphere, hence more clouds and a cooler Earth.

The theory makes some intuitive sense because over the last century the Sun has been unusually active - which means fewer cosmic rays, and a warmer climate on Earth. "We reconstructed solar activity going back 11,000 years," relates Sami Solanki. "And across this period, the level of activity we are seeing now is very high - we coined the term 'grand maximum' to describe it. We still have the 11-year modulation on top of the long-term trend, but on average the Sun has been brighter and the cosmic ray flux lower."

There is evidence too that cosmic rays and climate have been intertwined over timescales of millennia in the Earth's past. And the theory received some experimental backing when in October 2006, Henrik Svensmark's team published laboratory research showing that as the concentration of negative ions rose in air, so did the concentration of particles which could eventually become condensation nuclei.

Other scientists, meanwhile, had started putting the idea to the test in the real world. In 1947, British meteorologists began deploying instruments in various sites across the country to measure sunlight. Whether through foresight or luck, they included one feature which was to prove very useful; the capacity to measure the relative amounts of direct and diffuse light. It is the difference between a sunny day, when light streams directly from above, and a cloudy day, when it seems to struggle in from everywhere, and photographers give up and go home.

Giles Harrison from Reading University realised that the UK Met Office's record of hourly readings from its sunlight stations could be used to plot the extent of cloud cover over a period going back more than 50 years; the larger the ratio of diffuse to direct light, the cloudier the skies.

By chance, cosmic rays have been recorded continuously over almost exactly the same period. So Dr Harrison's team compared the two records, looking for a correlation between more intense cosmic rays and more clouds. "We concluded that there is an effect, but that it is small - 'small but significant' was how we described it," he recalls. "It varied UK cloud cover only by about 2%, although we suggested it would have a larger effect on centennial timescales; and it's difficult to assess what effect this would have on global surface temperature." He concludes it would be premature to lay global warming at the door of cosmic rays. Perhaps surprisingly, you will find no references to his work in The Chilling Stars.

In July, Mike Lockwood from the UK's Rutherford-Appleton Laboratory attempted a definitive answer to the question with what appeared to be a simple method. He simply looked at the changing cosmic ray activity over the last 30 years, and asked whether it could explain the rising temperatures. His conclusion was that it could not. Since about 1985, he found, the cosmic ray count had been increasing, which should have led to a temperature fall if the theory is correct - instead, the Earth has been warming. "This should settle the debate," he told me at the time.

It has not. Last month Dr Svensmark posted a paper on the DNSC website that claimed to be a comprehensive rebuttal. "The argument that Mike Lockwood put forward was that they didn't see any solar signal in the surface temperature data," he says. "And when you look at [temperatures in] the troposphere or the oceans, then you do see a solar signal, it's very clear."

Dr Lockwood disagrees; he says he has re-analysed the issue using atmospheric temperatures, and his previous conclusion stands. And he thinks the Svensmark team has been guilty of poor practice by not publishing their argument in a peer-reviewed scientific journal. "Lots of people have been asking me how I respond to it; but how should I respond to something which is just posted on a research institute's website?" he asks. "This isn't on, because the report title says it is a 'comprehensive rebuttal'; if it were that, then it would be his duty to publish it in a scientific journal and clean up the literature - that's how science filters out what is incorrect, and how it comes to a consensus view as to what is correct." This dispute presumably has some distance to run.

But Mike Lockwood's larger conclusion that current warming has nothing to do with solar changes is backed up by others - notably the IPCC, which concluded earlier this year that since temperatures began rising rapidly in the 1970s, the contribution of humankind's greenhouse gas emissions has outweighed that of the Sun by a factor of about 13 to one.

Even though misguided journalists have sometimes mistaken his work as implying a solar cause to modern-day warming, Sami Solanki agrees with the IPCC verdict. "Since 1970, the cosmic ray flux has not changed markedly while the global temperature has shown a rapid rise," he says. "And that lack of correlation is proof that the Sun doesn't cause the warming we are seeing now."

Even to prove that the link between cosmic rays and cloud cover matters in the real world needs a lot more work, observes Joanna Haigh. "You need to demonstrate a whole long chain of events - that the atmosphere is ionised, then that the ionised particles act to nucleate the condensation of water vapour, then that you form droplets, and then that you get clouds; and you have to show it's important in comparison to other sources of nucleation. "And that hasn't been demonstrated. Proponents of this mechanism have tended to extrapolate their results beyond what is reasonable from the evidence."

And Giles Harrison believes climate sceptics need to apply the same scepticism to the cosmic ray theory as they do to greenhouse warming - particularly those who say there are too many holes in our understanding of how clouds behave in the man-made greenhouse. "There is some double-speak going on, as uncertainties apply to many aspects of clouds," he says. "If clouds have to be understood better to understand greenhouse warming, then, as we have only an emerging understanding of the electrical aspects of aerosols and non-thunderstorm clouds, that is probably also true of any effect of cosmic rays on clouds."

Dr Svensmark agrees it would be wrong for anyone to claim the case has been proved. "If anyone said that there is proof that the Sun or greenhouse gases alone are responsible for the present-day warming, then that would be a wrong statement because we don't really have proofs as such in the natural sciences," he says.

Two events loom on the horizon that might settle the issue once and for all; one shaped by human hands, one entirely natural. At Cern, the giant European physics facility, an experiment called Cloud is being constructed which will research the notion that cosmic rays can stimulate the formation of droplets and clouds. There may be some results within three or four years.

By then, observations suggest that the Sun's output may have started to wane from its "grand maximum". If it does, and if Henrik Svensmark is right, we should then see cosmic rays increase and global temperatures start to fall; if that happens, he can expect to see a Nobel Prize and thousands of red-faced former IPCC members queuing up to hand back the one they have just received.

But if the Sun wanes and temperatures on our planet continue to rise, as the vast majority of scientists in the field believe, the solar-cosmic ray concept of global warming can be laid to eternal rest. And if humankind has done nothing to stem the rise in greenhouse gas emissions by then, it will be even harder to begin the task.


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