Saturday, August 27, 2011

Heart disease risk inherited through genes, not behaviour

Amazing: They have just shown that lifestyle is irrelevant but still cannot help themseves from preaching the lifestyle gospel. There's a lot of religion in all the "sciences" as far as I can see. These guys are just as much men of faith as any Christian

Parents increase their child's risk of coronary heart disease through their genes and not through the family's diet or lifestyle, a new study shows.

Children born to parents with CHD are 40 to 60 per cent more likely to develop the condition themselves, but growing up in an unhealthy household is of little importance.

Although children of people who suffer from the condition were already known to be at increased risk, it was not previously clear whether this was due to genetics or because children of unhealthy parents adopt similar lifestyles.

But a study of more than 80,000 men and women who were adopted as children showed that susceptibility to the disease is transmitted in the womb and not in the home.

Smoking, eating unhealthy food and avoiding exercise still play a major role in an individual's chance of developing CHD, doctors said, but the risk that is passed down through families is based on DNA rather than behaviour.

Researchers at Lund University in Sweden, where nearly all residents are registered on a national health care database, compared the medical records of adoptees to both their biological and adoptive parents.

They found that adoptees who had at least one biological parent with CHD had up to 60 per cent more chance of suffering the disease themselves, compared with a control group.

In contrast, growing up in a home with adoptive parents who suffered from CHD resulted in no additional risk for the child, even if both parents had the disease.

Prof Kristina Sundquist, who led the study, said it showed that inherited risk of CHD is genetic and parents' lifestyles are not to blame for passing it on to their children.

She said: "Of course it is always important to think about your own lifestyle but this study shows you cannot blame families for passing on poor lifestyles to their children."

Prof Peter Weissberg, medical director of the BHF, said: "This study tells us that genes are very important but no matter what genes you have, you still need to pay attention to your lifestyle."


Antidepressants 'cut bowel and brain cancer risk'

This is interesting but it would be incautious to assume that what works with depressed people will work with normals.

Furthermore, it can reasonably be assumed that depressed people are (for instance) less active and it may in some way be the lower level of activity (or other factors associated with depression) that produced the effect rather than the medication

A commonly-prescribed type of antidepressant cuts the risk of bowel cancer by up to a fifth, according to a study of 93,000 people.

Tricyclic antidepressants also reduce the risk of glioma - the most common type of brain cancer - by up to two-thirds, found the study by academics at three British universities. Taking larger doses for longer increases the preventative effect, the researchers found.

Although the results, based on data from the General Practice Research Database, are startling, it is highly unlikely such drugs would be widely prescribed to those without mental health problems because of their side-effects. Many are sedatives, for example.

Nevertheless, the academics are excited because they say people at a genetically higher risk of the two types of cancer could be prescribed them.

The finding could also lead to the development of specifically designed pharmaceuticals to tackle bowel and brain cancer, said Dr Tim Bates, of Lincoln University and New-Use Therapeutics, a drugs development company. He explained that tricyclic antidepressants worked by attacking the "Achilles' heel" of some cancer cells, their mitochondria. These are the chemical powerhouses that enable cells to function.

He said: "As cancer mitochondria are biochemically different from mitochondria in normal non-cancer cells, they represent an Achilles' heel." Tricyclic antidepressants appeared to interfere with the normal working of mitochondria in bowel and glioma cancer cells, he added.

He went on: "The cancer prevention action of these drugs may translate into one that is also useful in treating glioma, both in adults and in children, and colorectal cancer."

The study, paid for with £75,000 from the publicly-funded Medical Research Council, compared about 31,500 people with cancer with about 61,500 people without, and was adjusted for age, gender, smoking, obesity and other factors.

It showed that people on tricyclic antidepressants were between 16 and 21 per cent less likely to have developed bowel cancer, with those who had been taking them at higher doses for longer receiving greater protection. Bowel cancer is the second bigger cancer killer in Britain after lung cancer, killing 16,000 people a year.

For glioma, tumours of the brain and spine, which kill up to 2,000 a year, the reduced risk was between 41 and 64 per cent. There was no effect on reducing incidence of other types of cancer.

The research has been published in the British Journal of Cancer.


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