OREGON STATE UNIVERSITY

college of public health and human sciences

Lower vitamin D could increase risk of dying, especially for frail, older adults

CORVALLIS, Ore. – A new study concludes that among older adults – especially those who are frail – low levels of vitamin D can mean a much greater risk of death.

The randomized, nationally representative study found that older adults with low vitamin D levels had a 30 percent greater risk of death than people who had higher levels.

Overall, people who were frail had more than double the risk of death than those who were not frail. Frail adults with low levels of vitamin D tripled their risk of death over people who were not frail and who had higher levels of vitamin D.

“What this really means is that it is important to assess vitamin D levels in older adults, and especially among people who are frail,” said lead author Ellen Smit of Oregon State University.

Smit said past studies have separately associated frailty and low vitamin D with a greater mortality risk, but this is the first to look at the combined effect. This study, published online in the European Journal of Clinical Nutrition, examined more than 4,300 adults older than 60 using data from the Third National Health and Nutrition Examination Survey.

“Older adults need to be screened for vitamin D,” said Smit, who is a nutritional epidemiologist at OSU’s College of Public Health and Human Sciences. Her research is focused on diet, metabolism, and physical activity in relation to both chronic disease and HIV infection.

“As you age, there is an increased risk of melanoma, but older adults should try and get more activity in the sunshine,” she said. “Our study suggests that there is an opportunity for intervention with those who are in the pre-frail group, but could live longer, more independent lives if they get proper nutrition and exercise.”

Frailty is when a person experiences a decrease in physical functioning characterized by at least three of the following five criteria: muscle weakness, slow walking, exhaustion, low physical activity, and unintentional weight loss. People are considered “pre-frail” when they have one or two of the five criteria.

Because of the cross-sectional nature of the survey, researchers could not determine if low vitamin D contributed to frailty, or whether frail people became vitamin D deficient because of health problems. However, Smit said the longitudinal analysis on death showed it may not matter which came first.

“If you have both, it may not really matter which came first because you are worse off and at greater risk of dying than other older people who are frail and who don’t have low vitamin D,” she said. “This is an important finding because we already know there is a biological basis for this. Vitamin D impacts muscle function and bones, so it makes sense that it plays a big role in frailty.”

The study divided people into four groups. The low group had levels less than 50 nanomole per liter; the highest group had vitamin D of 84 or higher. In general, those who had lower vitamin D levels were more likely to be frail.

About 70 percent of Americans, and up to a billion people worldwide, have insufficient levels of vitamin D. And during the winter months in northern climates, it can be difficult to get enough just from the sun. OSU’s Linus Pauling Institute recommends adults take 2,000 IU of supplemental vitamin D daily. The current federal guidelines are 600 IU for most adults, and 800 for those older than 70.

“We want the older population to be able to live as independent for as long as possible, and those who are frail have a number of health problems as they age,” Smit said. “A balanced diet including good sources of vitamin D like milk and fish, and being physically active outdoors, will go a long way in helping older adults to stay independent and healthy for longer.”

Researchers from Portland State University, Drexel University of Philadelphia, University of Puerto Rico and McGill University in Montreal contributed to this study. It was funded in part by the National Institutes of Health and a grant from OSU.

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Ellen Smit, 541-737-3833

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Milk is one of the sources of vitamin D. About 70 percent of Americans, and up to a billion people worldwide, have insufficient levels of vitamin D.

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Milk is one of the sources of vitamin D. About 70 percent of Americans, and up to a billion people worldwide, have insufficient levels of vitamin D.

Physical health problems increase use of mental health services

CORVALLIS, Ore. – People who experience a physical health problem, from diabetes and back pain to cancer or heart disease, are three times more likely to seek mental health care than patients who report having no physical ailment, according to a new study by Oregon State University researchers.

The study, which is now online in the journal Health Services Research, indicates there is a need for better-coordinated care between physical and mental health providers. It is the first nationally representative study that statistically shows a major link between physical health and mental health

“I see this study as a way to set benchmark data so that policy makers can determine how to best transition to a system that hopefully will coordinate physical and mental care,” said lead author Jangho Yoon, a health policy economist with OSU who specializes in mental health policy issues.

“The Affordable Care Act is supposed to have better coordinated care and interplay between physical and mental health providers, so this has really important implications because before our study, baseline data didn’t exist.”

Yoon used data from 2004 and 2005 Medical Expenditure Panel Surveys to identify more than 6,000 adults for his study. He only used people who had not reported a previous physical or mental health condition. Compared to those who did not have a physical health problem, people who developed a physical health condition had a threefold increase in the likelihood of seeking mental health care.

Interestingly, even after he controlled for those who developed the most catastrophic medical conditions, such as cancer, stroke and heart attack, he found the same results.

“The interplay between our physical and mental health has long been suspected,” Yoon said. “When I have back pain, I feel stressed. And if it impacts my ability to work, or to do my usual activities, then I can feel upset or even a bit depressed. But no large scale studies existed that showed the statistical proof of this correlation.”

Yoon, who is an assistant professor in the College of Public Health and Human Sciences at OSU, said the study included people who sought mental health providers, prescriptions for mental health issues, or both.

He said the study also found that those patients who said they perceived their health issue as severe were more likely to seek mental health services.

The researchers said a simple screener survey, such as the 16-question Substance Abuse/Mental Illness Screener (SAMISS), used in a busy clinical setting could be an effective tool to help health providers attain proper mental health treatment for their patients.

“This is a win-win,” Yoon said. “There is a chance of cost-savings in our medical system if we identify potential mental health problems early, before they become more severe. And more importantly, coordinated care and early intervention leads to better health outcomes, and better care for the patient.”

Stephanie Bernell of OSU’s health management and policy program, contributed to the study.

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Frail, older adults with high blood pressure may have lower risk of mortality

CORVALLIS, Ore. – A new study suggests that higher blood pressure is associated with lower mortality in extremely frail, elderly adults.

The study, published today in the Journal of the American Medical Association’s (JAMA) Archives of Internal Medicine, looked at a nationally representative group of 2,340 adults ages 65 and older. The researchers found that lower blood pressure protected healthier, robust older adults but the same may not be true for their more frail counterparts.

Lead author Michelle Odden, a public health epidemiologist at Oregon State University, said blood pressure rises naturally as people age. Her study used walking speed as a measure of frailty. Participants were asked to walk a distance of about 20 feet at their normal rate. Those who walked less than 0.8 meters per second were defined as slower walkers. Those who walked faster than 0.8 meters per second were in the second group of more robust adults, who also had a lower prevalence of diabetes, coronary heart disease, stroke and heart failure.

The third group included those who were not able to complete the walking test for various reasons, including inability to walk 20 feet.

“As we age, our blood vessels lose elasticity and becomes stiff,” Odden said. “Higher blood pressure could be a compensatory mechanism to overcome this loss of vascular elasticity and keep fresh blood pumping to the brain and heart.”

Odden said the mortality differences between the fast walkers and slow walkers or non-completers can be explained simply – everyone ages differently.

“There is a profound difference in the physiological age of an 80-year-old man who golfs every day, and someone who needs a walker to get around,” she said. “So in the fast walkers, high blood pressure may be more indicative of underlying disease, not just a symptom of the aging process.”

Among the faster walkers, those with high blood pressure had a 35 percent greater risk of dying compared with those with normal blood pressure.

In contrast, there was no association between high blood pressure and mortality in the slow walking group. Strikingly, those who were unable to complete the walking test had the opposite results – those with higher blood pressure had a 62 percent lower mortality rate.

Since this is one of the first studies to examine walking speed, mortality and blood pressure, Odden cautioned against people making health decisions based on these early findings.

“Any sort of decision regarding medication use should be done in consultation with a physician,” she said. “Our study supports treating high blood pressure in healthy, active older adults. But in frail older adults, with multiple chronic health conditions, we need to take a closer look at what sorts of effects high blood pressure could serve and whether having a higher blood pressure could be protective.”

Odden is an expert on chronic disease and disease prevention in aging populations, particularly in regard to cardiovascular health and kidney disease. Her work is funded by the National Institute on Aging and the American Heart Association Western States Affiliate.

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Michelle Odden, 541-737-3184

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OSU Pharm.D. student takes a blood pressure reading at a screening. Photo: courtesy of Oregon State University.

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This chart designed by OSU College of Public Health and Human Sciences researcher Michelle Odden shows the link between elevated blood pressure, walking speed, and mortality. Courtesy of Michelle Odden/Oregon State University.

Moderate alcohol consumption may help prevent bone loss

CORVALLIS, Ore. – Drinking a moderate amount of alcohol as part of a healthy lifestyle may benefit women’s bone health, lowering their risk of developing osteoporosis.

A new study assessed the effects of alcohol withdrawal on bone turnover in postmenopausal women who drank one or two drinks per day several times a week. Researchers at Oregon State University measured a significant increase in blood markers of bone turnover in women after they stopped drinking for just two weeks.

Bones are in a constant state of remodeling with old bone being removed and replaced. In people with osteoporosis, more bone is lost than reformed resulting in porous, weak bones. About 80 percent of all people with osteoporosis are women, and postmenopausal women face an even greater risk because estrogen, a hormone that helps keep bone remodeling in balance, decreases after menopause.

Past studies have shown that moderate drinkers have a higher bone density than non-drinkers or heavy drinkers, but these studies have provided no explanation for the differences in bone density. Alcohol appears to behave similarly to estrogen in that it reduces bone turnover, the researchers said.

In the current study, published online today in the journal Menopause, researchers in OSU’s Skeletal Biology Laboratory studied 40 early postmenopausal women who regularly had one or two drinks a day, were not on any hormone replacement therapies, and had no history of osteoporosis-related fractures.

The researchers found evidence for increased bone turnover – a risk factor for osteoporotic fractures – during the two week period when the participants stopped drinking. Even more surprising: the researchers found that less than a day after the women resumed their normal drinking, their bone turnover rates returned to previous levels.

“Drinking moderately as part of a healthy lifestyle that includes a good diet and exercise may be beneficial for bone health, especially in postmenopausal women,” said Urszula Iwaniec, associate professor in the College of Public Health and Human Sciences at OSU and one of the study’s authors. “After less than 24 hours to see such a measurable effect was really unexpected.”

Iwaniec, OSU’s Skeletal Biology Laboratory director Russell Turner, and researcher Gianni Maddalozzo assisted OSU alumna Jill Marrone with the study, which was Marrone’s master’s thesis.

This study is important because it suggests a cellular mechanism for the increased bone density often observed in postmenopausal women who are moderate drinkers, Turner said.

The researchers said many of the medications to help prevent bone loss are not only expensive, but can have unwanted side effects. While excessive drinking has a negative impact on health, drinking a glass of wine or beer regularly as part of a healthy lifestyle may be helpful for postmenopausal women.

“Everyone loses bone as they age, but not everyone develops osteoporosis,” Turner said. “Being able to identify factors, such as moderate alcohol intake, that influence bone health will help people make informed lifestyle choices.”

The study was funded by grants from the National Institutes of Health and the John C. Erkkila, M.D. Endowment for Health and Human Performance.

Karin Hardin, Adam Branscum, Kenneth Philbrick and Lynn Cialdella-Kam of OSU co-authored the study, along with Anne Breggia and Clifford Rosen of the Maine Medical Center Research Institute.

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Urszula Iwaniec, 541-737-9925

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Urszula Iwaniec, associate professor in the College of Public Health and Human Sciences at OSU, pictured here with student Bailey Lindenmaier in the OSU Skeletal Biology Laboratory on campus.

Survey: Health care providers not checking for family food insecurity, barriers still exist

PORTLAND, Ore. – A survey of pediatric physicians and nurse practitioners in the Portland metro area shows that a majority are not regularly asking about household food practices, including nutritional quality or whether there is enough food in the home.

Oregon is one of the states ranked highest in “food insecurity,” or the proportion of households that have limited access to nutritionally adequate food on a regular basis. About 13.9 percent of households in Oregon are “food insecure” and Oregon also has one of the highest rates of childhood hunger.

The American Academy of Pediatrics has identified food security as one of the top health-related social issues that should be addressed in a pediatric visit. Yet, in a new study published online recently in the journal Preventive Medicine, only 13 percent of health care providers in the Portland area reported asking about household food sufficiency, and only 9 percent considered themselves knowledgeable about the prevalence of food insecurity in Oregon.

The study’s lead author, Anne Hoisington, an Oregon State University Extension specialist based at the Oregon Food Bank, said a positive aspect of the survey was that a large majority – almost 89 percent – of respondents said they would be willing to use a standardized screening question.

“A large percentage of our responding physicians and nurse practitioners were willing to engage, so I look at this as a huge opportunity that indicates that these providers want to learn more,” she said. “We already offer an online training class, and I’d like to see this taken a step further.”

The study showed that out of the 186 respondents, the health care providers who monitored food insecurity tended to be those with more years in practice.

Providers listed limited time available in the clinical visit as the main barrier to inquiring about the nutritional quality of their patients’ food. In contrast, however, the main barriers to inquiring about food sufficiency – whether everyone in the family has enough to eat – were discomfort in discussing food insecurity and inadequate knowledge about the topic.

“We found that the prospect of discussing food sufficiency seems to make some providers uncomfortable,” said Marc Braverman, a professor and Extension specialist in the College of Public Health and Human Sciences at OSU, who coauthored this study. “The topic is largely outside of their common practice, because food scarcity is perceived as a social problem rather than a medical problem, even though it has real and serious impacts on health.”

Hoisington, who is also a nutrition specialist in the College of Public Health and Human Sciences, said food scarcity taps into one of the most sensitive areas in parenting – a parent’s ability to care properly and provide resources for his or her child.

Ideally, Hoisington would like to develop a training video in collaboration with partners around Oregon that could be shared with pediatricians’ offices. The training video would help model how health providers could deal with this sensitive topic with an upset parent.

In addition, the researchers said doctors should have materials on hand about underutilized food assistance programs such as SNAP, so they can provide parents with resources.

Hoisington said since this survey was conducted several years ago, more than 2,000 Oregonians have gone through an online training course on food insecurity developed by OSU Extension. More than 10 percent of those were physicians, and most others are medical students, nurses, dieticians, and other health care providers.

The survey was a project of the Childhood Hunger Coalition, which includes OSU Extension, Oregon Food Bank, Oregon Health and Science University, the Oregon Health Authority’s WIC (Women, Infants, and Children) Program, Kaiser Permanente, and Partners for a Hunger-Free Oregon.

The next step is to conduct intervention studies, which are already in the works. Members of the Childhood Hunger Coalition are conducting pilot screenings and designing an intervention model in two clinics where doctors will screen patients on food insecurity.

 “With health care reform now a reality, I think there will be more focus on prevention,” Hoisington said. “Hopefully that will mean we will become more attentive to issues such as health care disparity, hunger, and food insecurity.”

Coauthors of this study included pediatrician Dr. Dana Hargunani and assistant professor Elizabeth Adams, both with OHSU, and Cheryl Alto with the Oregon WIC.

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Anne Hoisington, 503-282-0624

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Parents, not TV, may determine whether kids are active or couch potatoes

CORVALLIS, Ore. – Researchers at Oregon State University have confirmed what we knew all along – children in this country are increasingly sedentary, spending too much time sitting and looking at electronic screens.

But it’s not necessarily because of the newest gee-whiz gadgets – parents play a major factor in whether young children are on the move.

In two studies out online today in a special issue of the journal Early Child Development and Care devoted to “Parental Influences of Childhood Obesity,” OSU researchers examined how parenting style – whether a strict but loving parent or a less-involved and more permissive parent – was associated with sedentary behavior.

Overall, they found that children who had “neglectful” parents, or ones who weren’t home often and self-reported spending less time with their kids, were getting 30 minutes more screen time on an average each week day.

More disturbing to lead author David Schary – all of the children ages 2 to 4 were sitting more than several hours per day.

“Across all parenting styles, we saw anywhere from four to five hours a day of sedentary activity,” he said. “This is waking hours not including naps or feeding. Some parents counted quiet play – sitting and coloring, working on a puzzle, etc. – as a positive activity, but this is an age where movement is essential.”

Schary, a doctoral student in the College of Public Health and Human Sciences at OSU, said parents were grouped into four commonly used scientific categories – authoritative (high warmth and control), authoritarian (controlling, less warm), permissive (warm, low control), and neglectful (low control and warmth).

While all the children in the sample of about 200 families were sitting four to five hours in a typical day, parents in the more neglectful category had children who were spending up to 30 additional minutes a day watching television, playing a video game or being engaged in some other form of “screen time.”

“A half an hour each day may not seem like much, but add that up over a week, then a month, and then a year and you have a big impact,” Schary said. “One child may be getting up to four hours more active play every week, and this sets the stage for the rest of their life.”

Some might wonder whether parents who were less participatory during the week days made up for it during the weekends. Actually, just the opposite happened. Sedentary time increased nearly one hour each weekend day.

Bradley Cardinal, a professor of social psychology of physical activity at OSU, co-authored both papers with Schary. Cardinal said sedentary behavior goes against the natural tendencies of most preschool-age children.

“Toddlers and preschool-age children are spontaneous movers, so it is natural for them to have bursts of activity many minutes per hour,” he said. “We find that when kids enter school, their levels of physical activity decrease and overall, it continues to decline throughout their life. Early life movement is imperative for establishing healthy, active lifestyle patterns, self-awareness, social acceptance, and even brain and cognitive development.”

In a separate study, Schary and Cardinal looked at the same group of participants and asked about ways parent support and promote active play. They found that parents who actively played with their kids had the most impact, but that any level of encouragement, even just watching their child play or driving them to an activity – made a difference.

“When children are very young, playing is the main thing they do during waking hours, so parental support and encouragement is crucial,” Schary said. “So when we see preschool children not going outside much and sitting while playing with a cell phone or watching TV, we need to help parents counteract that behavior.”

Paul Loprinzi, who completed his doctorate at OSU and is now at Bellarmine University in Kentucky, contributed to this study.

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Moore Family Center grand opening set for June 6

CORVALLIS, Ore. – The Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health, a new research center at Oregon State University focused on healthy eating and whole foods, will celebrate its official opening on Wednesday, June 6.

The public reception will be from 2:15 to 3:30 p.m. at the Hallie E. Ford Center for Healthy Children and Families, at 26th and Campus Way on the OSU campus.

The event will honor Bob and Charlee Moore, founders of Bob’s Red Mill Natural Foods, whose $5 million gift made the new center possible.

Speaking at the event will be the new Moore Family Center director, Emily Ho, who is an associate professor of nutrition and a principal investigator in the Linus Pauling Institute at OSU. Tammy Bray, dean of the College of Public Health and Human Sciences, will also speak, along with OSU President Ed Ray. Bob and Charlee Moore will both be in attendance.

The academic center will build on the College of Public Health and Human Sciences’ research on nutrition, childhood obesity and related topics, and help promote healthy eating throughout Oregon and beyond.

“With a focus on whole foods, including whole grains, the center will be a catalyst in bringing together campus educators, researchers and those in community outreach to address our nation’s health in practical, concrete ways,” Ho said. “There is a huge gap between science and application, which our center is uniquely positioned to address.”

The gift provides endowments for the center’s director and an additional professor, along with two programmatic funds to support the center’s research and outreach, including a fund focused on childhood obesity.

This was the second largest gift OSU’s College of Public Health and Human Sciences has ever received. Its Hallie E. Ford Center for Healthy Children and Families was established in 2007 through an $8 million commitment from the late Oregon philanthropist.

Bob and Charlee Moore started their business in 1978 in an historic flour mill near Oregon City, with a mission to grind whole grains into flours, cereals and mixes for the local community and move people back to the basics with healthy whole grains, high-fiber and complex carbohydrates. Now based in Milwaukie, Ore., Bob's Red Mill has become a leading provider of whole grain natural foods with international distribution.

Guided by the university's strategic plan, The Campaign for OSU has raised more than $800 million toward its $1 billion goal.

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Michelle Williams, 541-737-6126

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Parenting Education Week May 20-26 casts spotlight on effective parenting

CORVALLIS, Ore. – National problems of childhood obesity and school readiness – and how effective parenting can play a role in overcoming these issues – is lending new urgency this year in Oregon to Parenting Education Week, which takes place May 20-26.

As a kickoff for the week, Gov. John Kitzhaber will sign a proclamation on Friday, May 11, in the Ceremonial Office at the Capitol.

Oregon State University’s Hallie E. Ford Center for Healthy Children and Families, which has taken a leadership role in parenting education in Oregon, will hold a series of events as part of Parenting Education Week. They include:

  • Monday, May 21, 3 p.m.: “Making the Link Between Parenting and Policy: Understanding the Impact of Parenting on Early Childhood Outcomes,” a presentation by Rebecca Parlakian of the Washington, D.C.-based Zero to Three.
  • Wednesday, May 23, 2 p.m.: A panel discussion on parenting education in Oregon
  • Friday, May 25, noon: “Measuring and Predicting Healthy Development in Young Children,” an analysis by Megan McClelland, associate professor in OSU’s College of Public Health and Human Sciences.

All presentations will take place at the Hallie Ford Center on campus and will be streamed live on the Web at: http://health.oregonstate.edu/hallie-ford/.

“Parenting skills are learned, and always have been,” said Denise Rennekamp, parenting education program coordinator for the Hallie Ford Center. “In the past perhaps those skills were gained from a family and extended community network. But today as people are more separated by distance, and parents have to work more, the ability to learn those skills and obtain that knowledge can be a struggle.”

Rennekamp says effective parenting education programs have been linked with decreased rates of child abuse and neglect, better physical, cognitive and emotional development in children, and increased parental knowledge of child development and parenting skills. A list of resources is available here: http://health.oregonstate.edu/hallie-ford/resources

Kathy Barber, a parenting education specialist with Pathways to Positive Parenting, an organization that offers parenting classes and workshops in Coos and Curry counties, said with limited resources and many demands, the skills and resources that researchers at the Hallie Ford Center offer have proven invaluable.

“OSU provides a solid foundation upon which to stand as we extend ourselves and dream big about what is possible to achieve for children and families,” she said. “It is a secure feeling to know that if there is a problem to be solved, or a need to be met regarding data, curricula, online reporting issues or conference content that I can get the help or resources I might need by calling any of the OSU team.”

Through the Oregon Parenting Education Collaborative, the Hallie Ford Center has taken a leadership role in evaluating the effectiveness of nonprofit programs that offer help to parents. The collaborative provides grants to nonprofit organizations to build systems, coordinate services, and provide programs for parenting education.

The collaborative is a partnership with The Ford Family Foundation, OSU, the Meyer Memorial Trust, The Collins Foundation and The Oregon Community Foundation.

Annual grants of $80,000 to $90,000 support regional parenting education “hubs.” The 12 hubs are in: Wallowa/Baker, Deschutes/Crook/Jefferson, Douglas, Linn/Benton, Hood River/Wasco and Coos/Curry, Columbia/Clatsop, Lincoln, Polk, Umatilla/Morrow, Lane and Siskiyou County, California. More information is available at: http://health.oregonstate.edu/hallie-ford/oregon-parenting-education-week/opec-hubs

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Denise Rennekamp, 541-737-1013

Annual student fashion show set for May 25

CORVALLIS, Ore. – The annual student-run fashion show featuring collections from juniors and seniors in Oregon State University’s professional apparel design program will take place Friday, May 25, beginning at 7 p.m. in the CH2M Hill Alumni Center on campus.

Presented by students in the Department of Design and Human Environment, the theme of this year’s show is “Cirque de la Mode,” which translates as Circus of Fashion. This show brings in representatives from the apparel industry from Portland and other local businesses.

The event is put on by Oregon State’s spring fashion show class which consists of 18 students, all of whom are either apparel design or merchandise management majors.

Doors open at 6:30 p.m. Tickets are $5 for standing room, $20 for general admission, $30 for preferred and $100 for V.I.P. For information, go to http://oregonstatefashionshow.com/

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Knee injuries in women linked to motion, nervous system differences

CORVALLIS, Ore. – Women are more prone to knee injuries than men, and the findings of a new study suggest this may involve more than just differences in muscular and skeletal structure – it shows that males and females also differ in the way they transmit the nerve impulses that control muscle force.

Scientists at Oregon State University found that men control nerve impulses similar to individuals trained for explosive muscle usage – like those of a sprinter – while the nerve impulses of women are more similar to those of an endurance-trained athlete, like a distance runner.

In particular, the research may help to explain why women tend to suffer ruptures more often than men in the anterior cruciate ligament of their knees during non-contact activities. These ACL injuries are fairly common, can be debilitating, and even when repaired can lead to osteoarthritis later in life.

More study of these differences in nervous system processing may lead to improved types of training that individuals could use to help address this issue, scientists said.

“It’s clear that women move differently than men, but it’s not as obvious why that is,” said Sam Johnson, a clinical assistant professor in the OSU School of Biological and Population Health Sciences.

“There are some muscular and skeletal differences between men and women, but that doesn’t explain differences in injury rates as much as you might think,” Johnson said. “No one has really studied the role of the nervous system the way we have in explaining these differences, specifically the way sensory information is processed and integrated with motor function in the spinal cord.”

In this study, just published in the European Journal of Applied Physiology, the scientists found that most aspects of spinal motor control and rapid activation of muscles were similar in 17 men and 17 women that were examined – with one exception. Men had a higher level of “recurrent inhibition,” which is a process in the spinal cord that helps select the appropriate muscle response.

Even a process as simple as walking is surprisingly complicated, as people process large amounts of information and use varying forces to move around obstacles, change direction or simply climb up a step. And when you slip on an icy patch, the need for extremely rapid and accurate muscle response might be all that stands between you and a broken hip.

For some reason, women tend to have knee motions that make them more susceptible to injury. Among other things, when landing from a jump their knees tend to collapse inward more than that of most men. They suffer significantly more ACL injuries during physical activity.

“We’re finding differences in nervous system processing that we believe are related to this,” Johnson said. “The causes for those differences are unclear, but it may be due either to a biological difference, such as hormones, or a cultural difference such as different exercise and training patterns.”

This research was supported by the National Athletic Trainers’ Association Research and Education Foundation. Researchers at Marquette University collaborated on the work.

While researchers continue to study what might help address this, Johnson said it’s already possible for women to be more aware of these common differences and do exercises that should reduce problems.

Many ACL injury prevention programs incorporate strength, balance, flexibility, and jump training. However, based on these and other findings, women – especially athletes – should consider training with motions more similar to those of their sport, such as squatting, lunging, jumping or cutting side-to-side.

Use of heavy weights may not really be necessary, Johnson said, so much as mimicking the motions that often cause this injury.

The study this story is based on is available online: http://bit.ly/Ius3gv

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Sam Johnson, 541-737-6801

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