Genetic Variant Increases Risk of Common Type Stroke

Topography of cerebral ischaemia after the obstruction of a major cerebral artery. The colours representing blood flow in order of highest to lowest flow are white, red, yellow, green, blue and black. (Credit: Dr I M Macrae, Wellcome Images)

 A genetic variant that increases the risk of a common type of stroke has been identified by scientists in a study funded by the Wellcome Trust and published online in Nature Genetics. This is one of the few genetic variants to date to be associated with the risk of stroke, and the discovery opens up new possibilities for treatment. 
Stroke is the second leading cause of death worldwide (causing more than one in ten of all deaths and more than six million deaths annually, according to the World Health Organization) and is a major cause of chronic disability in high-income countries. As the world's populations age, the impact of stroke on wellbeing is likely to increase further.
Several different mechanisms underlie strokes. One of the most common types is when blood flow is impaired because of a blockage to one or more of the large arteries supplying blood to the brain -- large artery ischaemic stroke. This accounts for more than one-third of all strokes.
Researchers from St George's, University of London, and Oxford University, working with scientists from Europe, America and Australia in one of the largest genetic studies of stroke to date, compared the genetic make-up of 10 000 people who had suffered from a stroke with 40 000 healthy individuals.
The researchers discovered an alteration in a gene called HDAC9 that affects a person's risk of large artery ischaemic stroke. This variant occurs on about 10 per cent of human chromosomes. Those people who carry two copies of the variant (one inherited from each parent) have nearly twice the risk for this type of stroke than those with no copies of the variant.
The protein produced by HDAC9 is already known to have a role in the formation of muscle tissue and heart development; however, the exact mechanism by which the genetic variant increases the risk of stroke is not yet known. A better understanding of the mechanism could lead to new drugs to treat or prevent stroke, although the researchers stress that this is still some way off.
Professor Hugh Markus, from St George's, University of London, who co-led the study, says: "This discovery identifies a completely new mechanism for causing stroke. The next step is to determine in more detail the relationship between HDAC9 and stroke and see whether we can develop new treatments that reduce the risk of stroke.
"Interestingly, there are already drugs available which inhibit the HDAC9 protein. However, it is important that we understand the mechanism involved before trialling the effects of these drugs on stroke."
The researchers went on to show that the new variant does not have the same effect on the risk of other types of stroke that include bleeding in the brain (haemorrhagic stroke).
Professor Peter Donnelly, Director of the Wellcome Trust Centre for Human Genetics in the University of Oxford, who co-led the study, says: "Our study shows that the different subtypes of stroke could involve quite different genetic mechanisms. This is really fascinating, and if it holds up more generally, will move us closer to personalised medicine, where treatments and preventions can be tailored more precisely to individual patients."
Dr Peter Coleman, Deputy Director of Research at The Stroke Association, who funded collection of some of the samples used in this study, said: "Over a third of strokes are caused by a blockage in one of the large blood vessels supplying blood to the brain (large artery stroke). Findings from this ground-breaking study appear to show a genetic link which may affect a person's risk of large vessel stroke.
"Further study is needed, but this research could potentially lead to new methods of screening and prevention for large vessel stroke, and ultimately, new methods of treatment."

National Wear Red Day for Women

Caption: National Wear Red Day for Women supporters

Many may have seen red last week; that’s because Mayor Ann Subrizi has declared Friday, February 3rd “National Wear Red Day for Women” in Milford, repots the New Milford Patch
People throughout the country are being encouraged to clad themselves in red to show their support for hear disease, which is also the number one killer of women. National Wear Red Day falls at an apt time given that February is also American Heart Month.
The day hopes to promote the American Heart Association’s red dress symbol, asking everyone to adorn their most favorite red garment.
"A sudden heart attack leaves so much behind," Subrizis stated.

Eating Foods Fried In Olive Or Sunflower Oil Not Tied To Heart Disease Or Earlier Death

In a new study published in BMJ on Tuesday, researchers find that consuming fried food is not linked to heart disease or earlier death, as long as the frying is done in in olive or sunflower oil. But they also note that the people they studied live in Spain, where like other Mediterranean countries they use olive or sunflower oil for frying, so this result would most likely be different in countries where people fry with solid and re-used oils.

Professor Pilar Guallar-Castillón from Autonomous University of Madrid, and colleagues set out to do the study because while high consumption of fried food has been tied to higher risk factors for heart disease, such as high blood pressure, high cholesterol and obesity, the link to heart disease itself had not been fully investigated.

People in Western countries use frying more than any other way of cooking food. Frying changes the nutritional content of food: it loses water and takes up fat, increasing its calorie content. Another thing that happens is that frying degrades oils, especially when re-used, creating more unhealthy trans fats and losing the healthier unsaturated fats. These unhealthier fats end up in the food that is eaten.

For the study, Guallar-Castillón and colleagues used data covering 40,757 adults aged 29 to 69 in the Spanish cohort of EPIC study.

EPIC (the European Prospective Investigation into Cancer and Nutrition study) is a large study of diet, health and lifestyle that has recruited in total about half a million participants in ten European countries.

None of the participants they studied had heart disease at the start of the study. Through trained interviewers, the participants gave information about their diet and cooking methods. Fried food was defined as being where frying was the only method used to prepare the food, and the participants were also asked whether the food was fried, battered, crumbed or sautéed.

Data about coronary heart disease events and deaths came from hospital discharge registers, population based registers of heart attacks and death registers.

When they analyzed the data, Guallar-Castillón and colleagues found that over the median follow-up of 11 years (up to 2004), there were 606 coronary heart disease events and 1,135 deaths (from all causes).

They then sorted the participants according to how much fried food was in their diet, so the ones who ate the least fried food were at the bottom of the list and the ones who ate the most were at the top.

They then compared the results in quartiles, for instance comparing the 25% who ate the least fried food (the first, or bottom quartile) with the next 25%, (the second quartile) and the third 25%, and lastly the fourth 25% (the ones who ate the most fried food).

When they did this they found, after adjusting for energy intake, BMI, high blood pressure and other risk factors, that the risk of coronary heart disease events was not significantly higher in the second, third and fourth quartiles compared to the first. (Eg the the multivariate hazard ratio of coronary heart disease in the fourth quartile was 1.08 (95% confidence interval 0.82 to 1.43; P for trend 0.74) compared to the first).

They also found the results did not vary between those who used olive oil and those who used sunflower oil to fry their food.

And there was no link between fried food cosumption and death (from any cause).

The authors conclude:

"In a Mediterranean country where olive and sunflower oils are the most commonly used fats for frying, and where large amounts of fried foods are consumed both at and away from home, no association was observed between fried food consumption and the risk of coronary heart disease or death."

In an accompanying editorial, Michael Leitzmann, a professor from the University of Regensburg in Germany, and Tobias Kurth, director of research at the Université Bordeaux in France, write that the study dispels the myth that "frying food is generally bad for the heart".

However, they also caution this "does not mean that frequent meals of fish and chips will have no health consequences".

They also note, as do the authors, that specific aspects of frying food, such as the type of oil used, could make a difference.