PDA

View Full Version : Left-handed women's risk of breast cancer higher



nonsequitur
26 Sep 2005, 06:33 PM
By Patricia Reaney Sun Sep 25, 7:36 PM ET

LONDON (Reuters) - Left-handed women are more than twice as likely as right-handers to suffer from breast cancer before reaching menopause, Dutch scientists said on Monday.

More than a million women are diagnosed with breast cancer worldwide each year. Three-quarters of cases occur after menopause, which usually begins around the age of 50.

Researchers at the University Medical Center in Utrecht in the Netherlands speculate that there is a shared origin early in life for both left handedness and developing breast cancer, possibly exposure to hormones in the womb.

"Left handedness is associated with breast cancer, most specifically pre-menopausal breast cancer," said Cuno Uiterwaal, an assistant professor of clinical epidemiology at the university, in an interview.

He and his colleagues studied 12,000 healthy, middle-aged women born between 1932-1941 who were part of a breast screening program. The scientists determined their hand preference and followed up their medical history to see which women developed breast cancer.

"If we take pre-menopausal and post-menopausal breast cancer then there was a 40 percent increased risk," Uiterwaal said of left-handed women.

But when they spilled it further the scientists found most of the excess risk was in breast cancer before the menopause.

"We found that left-handed women are more than twice as likely to develop pre-menopausal breast cancer as non-left handed women," the researchers said in the report published online by the British Medical Journal.

Other risk factors such as family history of breast cancer, numbers of pregnancies, smoking habits, and social and economic status were considered.

About 8 percent to 9 percent of women are left-handed. But the scientists said the findings should not alarm them.

"What our study intends to do is focus on this area. We do not know all the causes of breast cancer, that is why we should continue. This may be one new factor that leads us to a better understanding of the aetiology (cause of the illness)," Uiterwaal added.

About 5 percent to 10 percent of breast cancers are hereditary. Most are due to mutations in the BRCA1 or BRCA2 genes. The earlier the illness is diagnosed and treated, the better the prognosis is for the woman.

"Although the underlying mechanisms remain elusive, our results support the hypothesis that left handedness is related to increased risk of breast cancer," the researchers added.

from: here (http://news.yahoo.com/s/nm/20050925/ts_nm/cancer_breast_dc;_ylt=AgOmhnVS5fZtgqcs6mFvMRGs0NUE;_ylu=X3oDMTA3ODdxdHBhBHNlYwM5NjQ-)


Very weird.

MacGuffin
26 Sep 2005, 06:59 PM
sinister = on the left, unlucky

Left handed people are in league with the devil. Case solved.

PenguinHunter
26 Sep 2005, 09:12 PM
That is weird. Sounds like some kind of Victorian era conspiracy.

melancholeric
26 Sep 2005, 09:53 PM
"If we take pre-menopausal and post-menopausal breast cancer then there was a 40 percent increased risk," Uiterwaal said of left-handed women.
I didn't see that article mentioning anything about the actual risk of getting a breast cancer, so I googled. http://imaginis.com/breasthealth/statistics.asp
" The chance of developing invasive breast cancer during a woman's lifetime is approximately 1 in 7 (13.4%)."

40 % increase in that would be 18.76 %. But wait, the 13 % figure included both right and left handed women, so it's actually a bit lower than that.

And that was based on a sample of 12 000 women. Out of which 13 % got breast cancer. That's 1 560.

More googling. "Approximately 10-13% of the population is left-handed."

Now, 10 % of 12 000 is 1 200. Of which 18 % ( too high, but that only strengthens my point ) got breast cancer. That's 216. ( Which is approximately 13 % of the total cancer figure of the sample group, and within the error of inaccuracy of the estimated number of left handed women. )

In other words, whoever published that needs to take a few classes of maths and statistics.

FescherAlsDu
27 Sep 2005, 12:02 AM
"non-left handed people"
Makes it sound like they're missing a right hand entirely.

That is some creepy coincidence, though.

Amaris
27 Sep 2005, 01:45 AM
Missing a right hand? Sounds like a left one to me...

If that article's true, I'm pretty screwed. But I'm sure the devil will put things right in the end.. He has so far, at the very least.

registereduser
12 Oct 2005, 04:49 PM
Are they referring to people who write left-handed? I use both of my hands for different tasks. I write left handed, use scissors with my right, bat left handed, bowl right handed...etc. I'm guess I'm weird.