Archive for June 15th, 2006
By: Dana-Farber Cancer Institute
Researchers at Dana-Farber Cancer Institute in Boston have devised a
mathematical tool that predicts how the frequency of mammograms affects the number of lives saved by detecting breast cancers at an earlier stage.
With screening guidelines and financial coverage varying among health systems and insurers – sometimes dramatically - the model provides quantitative predictions of the mortality benefits, on average, in populations of women over the course of 40 years.
“We’re not advocating any particular interval for mammography screening,” says Sandra Lee, ScD, a biostatistician at Dana-Farber who developed the model along with Marvin Zelen, PhD, of Dana-Farber and the Harvard School of Public Health. “This is a preliminary tool to show policymakers the kind of information they can draw on to help them make decisions.”
Lee described the development of the mathematical model, which made use of data from several past clinical trials of mammography screening and from cancer databases, in a presentation at the annual meeting of the American Association for the Advancement of Science.
The mathematical tool generates comparative information that’s impossible to obtain in the real world, say the scientists, because clinical trials would require hundreds of thousands of volunteers following a variety of schedules over many years to demonstrate small mortality differences – and would be prohibitively expensive. Moreover, adds Lee, such trials would be ethically questionable because of the need for unscreened control groups.
At present, American Cancer Society guidelines recommend that women age 40 and older have a screening mammogram every year and that they “should continue to do so for as long as they are in good health.”
But payors differ in their coverage for the tests: in Great Britain, said Zelen, the National Health System pays for mammograms only at three-year intervals and doesn’t cover any screening whatsoever for women younger than 50, when the incidence of breast cancer is lower and mammograms are effective.
The model can be helpful to women, he said, by eliminating unnecessary screening exams when the chance of detecting an unknown breast cancer is too low to warrant them.
“It’s clear that the more mammograms you give, the more able you are to locate disease that a person didn’t know about,” Zelen says. But, testing with increasing frequency has diminishing returns, while boosting the odds of “false positives” that can be traumatic to women and lead to unneeded biopsies that drive up health costs.
Lee and Zelen, along with Hui Huang, MS, of Dana-Farber, described the model in 2004 in Statistical Methods in Medical Research. Among their conclusions:
• Annual screening from age 50 to 79 of women with average breast cancer risk would reduce mortality by 37 percent – compared to 30 percent with screenings every two years, and 26 percent with mammograms every three years.
• Beginning mammograms at age 40 – when breast cancer risk is low – rather than at 50, reduces overall risk of death by five percent because the incidence of cancer in the younger women is very low. However, Zelen said he believes screening women between 40 and 50 has merit because their breast cancers are more aggressive.
• If women underwent mammograms every two years beginning at 40 and then annually starting at 50, there would still be a 33 percent reduction in mortality.
• Because breast cancer risk increases with age, an alternative screening schedule derived from the model calls for fewer mammograms at early ages, but increasingly often later on. This “threshold” method provides for 18 screenings between 40 and 79, and predicts a mortality reduction of 26 percent.
Women who have a higher breast cancer risk because of their family history are advised to begin mammography at an early age. Using the model, say the researchers, health care providers can determine when to schedule mammograms depending on the amount of a woman’s extra risk.
The model also provides estimates of the relative costs incurred by screening populations of women at greater or lesser intervals - an important issue for health policymakers.
June 15th, 2006
By: Baylor College of Medicine
Maintaining good health is especially challenging for our nation’s 26 million women with disabilities, say experts at Baylor College of Medicine in Houston.
Barriers to accessing health care and lack of knowledge about wellness in the
context of disability have resulted in substantially higher rates of diabetes, obesity, hypertension, and depression among women with physical limitations.
“We have plenty of evidence that women with disabilities face incredible barriers to maintaining their health,” said Dr. Margaret Nosek, executive director of the Center for Research on Women with Disabilities at BCM. “What we need to do now is let the women and those who care about them know that wellness is possible despite physical limitations.”
Some things a woman with a disability can do to turn the odds in her favor include:
• Believe in yourself. You have the strength to meet challenges and make decisions. Messages of empowerment and connection with other women with disabilities can significantly reduce depression, one of the most problematic consequences of disability.
• Honor your body. Whatever it takes, keep moving. Stretch, breathe deeply, relax and eat well. Listen to your body and give it what it needs. You deserve to be healthy and safe.
• Be a thread in the fabric of your community. Relationships are the life blood of women. Whatever your limitations, it’s worth the trouble to get out and around and find new things to do. Spend time with the people who support you and appreciate you.
• Defy the myths. It is all right to ask for help or use a hearing aid, a cane, a scooter, or a wheelchair. Explore new ways to get things done and maintain your independent state of mind.
• Demand Answers. Refuse to accept the phrase, “That’s to be expected.” Make a list of questions before you see your doctor. Don’t give too much value to what’s “normal.” You’re the expert on yourself.
“Women with disabilities constitute one of the largest and fastest growing segments of the U.S. population,” says Nosek, who has a severe physical disability and uses a ventilator. “Thanks to advances in medical science, those of us who have had disabilities since childhood and women who acquire disabilities as they age are able to live much longer and have higher quality lives than even one generation ago.”
Over the past decade, CROWD has documented health disparities between women with disabilities and women in general.
June 15th, 2006
By: WUSTL
A new study suggests the brain is quickly turned on and “tuned in” when a person views erotic images.
Researchers at Washington University School of Medicine in St. Louis measured
brainwave activity of 264 women as they viewed a series of 55 color slides that contained various scenes from water skiers to snarling dogs to partially-clad couples in sensual poses.
What they found may seem like a “no brainer.” When study volunteers viewed erotic pictures, their brains produced electrical responses that were stronger than those elicited by other material that was viewed, no matter how pleasant or disturbing the other material may have been. This difference in brainwave response emerged very quickly, suggesting that different neural circuits may be involved in the processing of erotic images.
“That surprised us,” says first author Andrey P. Anokhin, Ph.D., research assistant professor of psychiatry. “We believed both pleasant and disturbing images would evoke a rapid response, but erotic scenes always elicited the strongest response.”
As subjects looked at the slides, electrodes on their scalps measured changes in the brain’s electrical activity called event-related potentials (ERPs). The researchers learned that regardless of a picture’s content, the brain acts very quickly to classify the visual image. The ERPs begin firing in the brain’s cortex long before a person is conscious of whether they are seeing a picture that is pleasant, unpleasant or neutral.
But when the picture is erotic, ERPs begin firing within 160 milliseconds, about 20 percent faster than occurred with any of the other pictures. Soon after, the ERPs begin to diverge, with processing taking place in different brain structures for erotic pictures than those that process the other images.
“When we present a stimulus to a subject - for example, when a picture appears on a screen - it changes ongoing brain activity in certain ways, and we can detect those changes,” Anokhin says.
Pictures appeared on a screen at 12 to 18 second intervals, and each picture remained on the screen for about 6 seconds. The subjects were instructed to do nothing other than look at the pictures.
A great deal of past research has suggested that men are more visual creatures than women and get more aroused by erotic images than women. Anokhin says the fact that the women’s brains in this study exhibited such a quick response to erotic pictures suggests that, perhaps for evolutionary reasons, our brains are programmed to preferentially respond to erotic material.
“Usually men subjectively rate erotic material much higher than women,” he says. “So based on those data we would expect lower responses in women, but that was not the case. Women have responses as strong as those seen in men.”
Because the electroencephalogram (EEG) technology cannot pinpoint specific brain structures involved in this visual processing, Anokhin says it’s not clear exactly which circuits are reacting to these visual scenes. Recent studies in primates recorded the electrical activity of single neural cells within the brain and have shown that the frontal cortex contains neurons that can discriminate between different categories of visual objects such as dogs versus cats. Whether or not the human prefrontal cortex contains special neurons that are “tuned” for sex remains a subject for future studies.
“The newer and more advanced technologies such as MRI and PET provide much better spatial resolution,” he says. “Those methods can better localize areas of brain activity, but ERPs have a much better temporal resolution. The EEG can record neuronal activity in real time. When measuring activity in milliseconds, any delay is undesirable.”
Most of Anokhin’s research is centered on the genetic and neurobiological bases of behavioral traits that might be associated with increased vulnerability to alcoholism and addictive disorders. He believes this study could contribute to that work by detecting differences between responses to images with different emotional significance. Because many psychiatric disorders also are associated with poor processing of signals associated with reward and pleasure, as well as sexual disturbances, he believes the way the brain processes emotional pictures, including erotic materials, might help scientists better understand some forms of mental illness.
June 15th, 2006
By: BMJ
The risk of infertility in women triples after the most major surgery for the inflammatory bowel disease ulcerative colitis, suggests research published ahead of print in the journal Gut.
The authors base their finding on an extensive trawl of print and online
research archives, and a detailed analysis of eight published studies. Infertility was defined as a failure to conceive after 12 months of trying.
Ulcerative colitis is a condition in which sores and inflammation develop along the lining of the large intestine, producing severe diarrhoea and rectal bleeding. It affects around 1 to 2% of the population. Surgical removal of the colon is sometimes needed to alleviate persistent and painful symptoms.
Ileal pouch anal anastomosis is a standard procedure in which the lower section of the large intestine is removed and a surgical pouch artificially created from the small intestine. This is then joined to a short remaining cuff of the rectum to ensure as normal bowel function as possible.
The evidence from the published studies showed that the risk of infertility after drug treatment was around 1 in 7 or 15%.
But this risk tripled to 48% after ileal pouch anal anastomosis. All patients seemed to be at risk of infertility, so there were no obvious factors among the patients or the procedure itself to account for the increased risk.
Based on previous X-ray studies of the fallopian tubes, which transport ripened eggs from the ovary to the womb, the authors suggest that such extensive surgery may scar or block these tubes.
June 15th, 2006
By: McMaster University
More women than men are working weekends new research from the DeGroote School of Business at McMaster University shows.
Nearly 20 percent of Canadians work weekends, mostly in the service sector and in part-time, temporary or seasonal jobs
. And because more women work in part-time and temporary jobs, most weekend workers are female.
Between 1991 and 1999, the percentage of people working weekends increased from 11 percent to 18.5 percent.
“Weekend workers are employed at a time when most others, including their family and friends are resting or socializing. It is an unsocial schedule that is disruptive to people’s leisure and family time,” says Isik Zeytinoglu, professor of human resources at DeGroote.
Businesses tend to stay open on weekends to increase profits, use capital efficiently by not keeping it idle and provide extended hours of service for consumers. However, for the people who are doing the work or providing the service, the cost of this convenience can be increased stress, physical and mental health problems and ultimately decreased productivity at work.
“An active social life outside of the workplace and a healthy work environment, as well as meaningful employment and economic stability, are important components of overall health and well being,” says Zeytinoglu.
The study is included in the book Decent Working Time: New Trends, New Issues launched this week in Geneva at the Conference of the International Labour Organization (ILO).
June 15th, 2006