Wednesday, November 04, 2009

Gentle exercise can cut heart disease deaths by 60 per cent (?)

Journal article here. It is a very mixed-up study with no clear control group that tries to look at stress, exercise, fitness and mortality all at once. What they ACTUALLY seem to have found was that fit people had fewer heart attacks, which is not exactly surprising. It is a hard study to disentangle but it appears that most people who exercised did NOT benefit from it

GENTLE exercise can dramatically cut the danger of an early death from heart disease, according to new research. Just 30 minutes of jogging or cycling three times a week has amazing results for people with heart problems – the UK’s biggest killer – a study has found. In just three months it slashed the risk of an early death by 60 per cent in those who followed the fitness regime.

The results will come as welcome news for thousands of Britons who suffer from heart-related illness. One-in-five men and one-in-seven women die of heart disease in the UK, equivalent to 250 deaths a day. Overall, 200,000 people die each year from conditions related to circulation, including strokes, heart attacks and heart disease. These figures are expected to go up as the population ages and thanks also to a rise in obesity, which leads to furring of arteries.

The study, released today, found the biggest gains were in patients who were also stressed. The authors believe it is because stress can quadruple the risk of death in people with heart problems. Exercise can offer the double benefit of reducing stress levels while also improving heart health.

The study concludes: “Exercise reduces mortality in patients with coronary artery disease…in part because of the effects on psycho social stress.” Patients with heart problems are usually put on drugs – statins to lower cholesterol and blood pressure pills – to reduce the risks....

This latest study by the Department of Cardiology in New Orleans and published in the American Journal of Medicine reveals in detail just how much these simple changes can boost lifespan. The team followed 522 cardiac patients, including 53 who had high stress levels and 27 control patients who had high stress levels but who refused cardiac rehabilitation.

Patients were offered 12 weeks of exercise classes, where they did 10 minutes of warm-up, 30 to 40 minutes of aerobic exercise such as walking, rowing or jogging, and then a 10-minute stretch to wind down. The classes were three times a week and patients were also asked to try to do a further one-to-three exercise sessions a week. They were also given advice on how to improve diet and lifestyle, and their progress was followed for up to six years.

Those who got fitter were 60 per cent less likely to die in the following six years. Exercise also helped reduce stress levels from one-in-10 patients to fewer than one-in-20 which in turn lowered the death rate for stressed patients by 20 per cent. However, the weight of patients did not change much, suggesting the benefits are from exercise alone.

Health charities welcomed the report. The British Heart Foundation, said: “This study proves once again that exercise has both psychological and physical benefits for patients with heart disease. “Health authorities must ensure that all suitable heart patients are offered cardiac rehabilitation. “Structured, well-resourced programmes have been shown to improve physical and psychological wellbeing and reduce mortality.”


People will die after swine flu vaccine - but it's just coincidence

Six people in Britain can be expected to die suddenly after having the swine flu vaccine but it will just be coincidence, researchers have said. With millions of people being vaccinated against the virus there is a real risk that coincidental events will be seen as reactions to the jab, a paper in The Lancet said.

Experts at Cincinnati Children's Hospital in America calculated the background rate of conditions that may be mistaken for vaccine reactions and warned that there is a risk people will shun the jab needlessly. Only if these background rates are exceeded will it point to a potential problem with the vaccine.

Medical experts have been told to watch for any cases of Guillain-BarrĂ© syndrome during the flu pandemic as some research suggested there was a link between a flu vaccine used in America in 1976 and the condition, in which the body’s immune system mistakenly attacks part of the nervous system and can be fatal in rare cases. However flu itself it also linked to the condition and about one in every 100,000 people a year.

Dr Steven Black and colleagues calculated that if 10 million people in Britain were vaccinated there would be around 22 cases of Guillain-Barré syndrome and six cases of sudden death would be expected to occur within six weeks of vaccination as coincident background cases.

Just over nine million people in priority groups, such as pregnant women and those with long-term illnesses, and another two million front line health and social care workers will be offered the vaccine in Britain over the next two months. Decisions will be taken soon over whether to offer the vaccine more widely.

The research also suggested that 397 per one million vaccinated pregnant women would be predicted to have a spontaneous abortion within one day of vaccination. But this is the rate of spontaneous abortion that would occur on any given day out of a group of one million pregnant women during a vaccination campaign or not.

Dr Black wrote: “Misinterpretation of adverse health outcomes that are only temporally related to vaccination will not only threaten the success of the pandemic H1N1 influenza vaccine programme, but also potentially hinder the development of newer vaccines. "Therefore, careful interpretation of vaccine safety signals is crucial to detect real reactions to vaccine and to ensure that temporally related events not caused by vaccination do not unjustly affect public opinion of the vaccine. "Development and availability of data banks that can provide locally relevant background rates of disease incidence are important to aid assessment of vaccine safety concerns.”

The researchers said although scientists know that events connected only by time does not prove cause and effect, the cases 'nonetheless raise public concern'.

Prof David Spiegelhalter, Winton Professor of the Public Understanding of Risk, University of Cambridge and Co-Director of Straight Statistics, said: "What a fine paper. If millions of people are vaccinated then just by chance we can expect bad things to happen to some of them, whether it's a diagnosis of autism or a miscarriage. "By being ready with the expected numbers of chance cases, perhaps we can avoid overreaction to sad, but coincidental, events. And why don't we ever see a headline 'Man wins lottery after flu jab'?"

Professor Robert Dingwall, University of Nottingham, said: "The difference between cause and coincidence is difficult enough for specialists to grasp, let alone the wider public. "However, this paper is very important in spelling out the fact that just because two events happen at the same time, they are not necessarily related. There is a background rate of death, disease and accidents that happen all the time regardless of what medical interventions are going on. "Confusing cause and coincidence may lead to serious policy mistakes that put people unnecessarily at risk. "I am sure that some coincidences will emerge from a high-profile vaccination campaign and we must be careful not to be misled by them."

Meanwhile the World Health Organisation said that pregnant women could be immunised with any of the vaccines licensed for use against swine flu. Dr Marie-Paule Keiny, from the WHO, said: “ Sage (the Strategic Advisory Group of Experts) has concluded that the safety profiles are good and recommend that pregnant women can be immunised with any of the licensed vaccines.” The WHO also recommended that one dose was sufficient to immunise children.


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