Sunday, November 03, 2013

Sections of the Australian medical community question Catalyst program about cholesterol and heart disease

The Australian public broadcaster has done some good for once, blowing the whistle on the cholesterol/statin myths

The ABC's medical science program Catalyst is under fire from some sections of the medical community for a two-part special that questions the scientific evidence linking cholesterol to heart disease.

Recently, Catalyst described the claim that saturated fats and cholesterol causes heart attacks as one of the biggest myths of medical history.

The most recent claim put forward by the program is that the anti-cholesterol medication called Statins is a massively over-prescribed drug and has no guarantee of reducing heart attack

The program goes further to say that the drug can, instead, do serious harm to the health of people taking them.

"All drugs have side effects and when you look at the clinical trials, it suggests that the side effect profiles are quite low," Catalyst presenter Dr Maryanne Demasi told ABC's PM program.

"But when you look at side effects in the general population, they’re a lot higher. And when you speak to doctors who are in clinical practice, they say that sometimes 20, 25, up to 30 per cent of their patients experience these side effects."

She says that if patients are not getting a benefit in having a longer lifespan from these drugs then patients need to question whether or not they expose themselves to the risks of these drugs.

Professor Emily Banks, the chair of the Advisory Committee on the Safety of Medicines, says the program may prompt people not to take necessary medicines.

But Dr Demasi says she has a responsibility to inform the public that people may using the drugs unnecessarily.

"I share her concern that patients will stop taking their medication unnecessarily but we also have a responsibility to tell people that the majority of people on these drugs may be on these drugs unnecessarily," she said.

"We have a duty of care to those people as well."

The National Heart Foundation of Australia maintains there is a clear link between saturated fat, cholesterol and heart disease, contrary to the Catalyst report.

The Heart Foundation said it has serious concerns about the conclusions presented in the ABC Catalyst program and is "shocked by the disregard for the extensive evidence upon which the Heart Foundation's recommendations are made".

"Australians need to be aware that the information presented by the ABC is not supported by the Heart Foundation," a statement said.

"There is international scientific consensus that replacing saturated fat with ‘good’ unsaturated fat, in particular polyunsaturated fat, reduces your risk of heart disease."

The Australian Medical Association supported the broadcast of the program, but added that it was important to have "balance" and "debate".

The program includes a warning advising viewers it is not intended as medical advice.


Australia:  Barnaby Joyce correct on bird flu risk in free-range chicken farms

Federal Agriculture Minister Barnaby Joyce has sounded a warning about free-range egg production leading to an increase in bird flu.  Senator Joyce says a decision by supermarket giant Woolworths to phase out eggs from caged production poses a major threat to the industry.

His comments came after 400,000 chickens were destroyed at an egg farm in Young, central-west NSW, after becoming infected with the H7 strain of avian influenza. Ten days later the Department of Primary Industries announced a nearby farm had also become infected. It is believed the infection spread from free-range chickens on the first farm.

"I think a big point to remember from this, and this is one of the discussions I'll be having with some of the supermarkets, is this virus got into the caged-bird population from the free-range bird population," Senator Joyce told ABC radio last month.

"What we see is that you've got the avian flu in ducks, and when the ducks have contact with the birds outside in the free-range form, it brings the disease into the shed. And if we want to move to just free-range birds, this is going to be a problem that's going to reoccur and reoccur and reoccur."

ABC Fact Check asked Senator Joyce for the basis for his claim - that greater free-range egg production will lead to an increase in bird flu incidents. A spokeswoman said the Department of Agriculture would answer on his behalf, as it provides advice to the minister. The department said free-range birds will have exposure to wild birds and contaminated feed and water, which could lead to avian flu infections.

Fact Check examines whether Senator Joyce's fears are well-founded.

How avian influenza is spread

Avian influenza is a viral disease among birds which usually poses little risk to humans. The H7 strain, which is found in Australia, is not harmful to humans, while the H5N1 strain has caused several hundred deaths overseas. The disease can infect domestic poultry, wild birds and even pigs, tigers, leopards and domestic cats. Symptoms range from the mild to quickly fatal.

Wild birds, particularly ducks, are the primary carriers of avian influenza. They can spread the virus to chickens through direct contact or by contaminating their feed or water supplies with faeces or feathers.

Free-range chickens at greater risk

The two main types of poultry farms are caged and free-range. About 30 per cent of Australian chickens raised for egg production are free-range or barn laid.

Facilities vary, but most free-range farms let chickens roam paddocks throughout the day. During this time they are exposed to all the elements, in particular puddles and dams, which can contain avian influenza. Roaming free, the chickens are also more likely to come into direct contact with wild birds carrying the disease. The NSW Department of Primary Industries says because free-range chickens require access to the outdoors, bird-proofing their sheds is "practically impossible".

Dr Peter Scott, a poultry veterinarian and senior research fellow at the University of Melbourne, says not only are free-range farms at higher risk, there is also concern free-range chickens will infect caged chickens with avian influenza.

"I've spoken to poultry farmers who once saw the idea of a free-range farm as a lucrative side endeavour and are now shying away from the prospect because they're worried the free-range hens will infect the caged birds," Dr Scott said.

"And there's no way to commercially vaccinate against this when it happens. It's like vaccinating against all the strands of the common cold - too tricky and too expensive."

Dr Andrew Peters, an avian veterinarian and lecturer in veterinary pathology at Charles Sturt University, agrees. "Because of the nature of how the disease spreads, if free-range hens are more commonly in contact with water pools and dams that contain the influenza, it is safe to say they are in greater danger of being infected than caged hens".

The CSIRO's Australian Animal Health Laboratory in Geelong, the national reference laboratory for avian influenza, said in a media release that "poultry, feed and water, if exposed to AI-infected wild birds, may be infected or contaminated". However it also noted that influenza carried by wild birds causes very few diseases in healthy domestic birds. It said the risk of infection could be "mitigated" if farmers put appropriate measures in place.

The verdict

It is almost impossible to stop free-range chickens coming into contact with avian influenza when they leave the shed. Caged chickens are not exposed in such a way. If farmers do not tighten up the measures they put in place to stop free-range birds coming into contact with the disease, then it is likely avian influenza will continue to infect free-range populations.

Senator Joyce's claim that this is going to "reoccur and reoccur and reoccur" if the industry shifts to free-range is correct.


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