Scholarship & CreativityPedometers motivate those with diabetes to walk
The use of a pedometer and a Web site that tracked physical activity proved to be powerful motivators for people with diabetes who participated in a recent walking study by researchers from the U-M Health System and VA Ann Arbor Healthcare System. The study also suggests that certain types of goal-setting may be more effective than others.
Participants wore pedometers and received automated weekly goals based on their previous week's walking activity. Half received "lifestyle goals," meaning any step taken during the day counted. The other half received "structured goals," in which only steps taken during long walks of at least 10 minutes counted. These participants had a smaller target number of steps to take in a day than the lifestyle group.
Participants in both groups increased their walking significantly during the program and there was no difference between the groups in terms of increased walking. The type of goals participants were given in the six-week study, however, strongly influenced their satisfaction with the program. Those who received lifestyle goals were more satisfied with the walking program and wore the pedometer more days and for more hours during each day, than those who received structured goals.
The finding sheds light on a debate among exercise experts about the ways in which people should increase their levels of activity.
"Walkers in the group where every step counted experienced the same benefit as those who just had their bout steps recorded," says lead author Dr. Caroline Richardson, assistant professor in the Department of Family Medicine and research scientist at the Veterans Affairs Health Services Research and Development. "The fact that they were also more satisfied with their program suggests that this approach may be more successful for many people than a program that only recognizes long periods of activity."
The study appears in the International Journal of Behavioral Nutrition and Physical Activity.
Other authors were Kathleen Mehari, Laura McIntyre, Adrienne Janney, and Laurie Fortlage, all from the Medical School; Ananda Sen, School of Public Health (SPH); Victor Strecher, SPH and the Comprehensive Cancer Center; and senior author John Piette, U-M Department of Family Medicine and the VA.
Sinus problems treated effectively with saline irrigation
An inexpensive, safe and easy treatment is an effective method for treating chronic nasal and sinus symptoms more effective, in fact, than commonly used saline sprays, according to a new study from U-M Health System researchers.
The study is the first of its kind to show greater efficacy of saline irrigation treatments versus saline spray for providing short-term relief of chronic nasal symptoms, the authors report. Participants in the study who were treated with irrigation experienced a much greater benefit than those who were treated with saline spray, in terms of both the severity and frequency of their symptoms.
"The irrigation group achieved a clinically significant improvement in quality of life in terms of the severity of their symptoms, whereas the spray group did not," says lead author Dr. Melissa Pynnonen, clinical assistant professor in the Department of Otolaryngology. "Strikingly, they also experienced 50-percent lower odds of frequent nasal symptoms compared with the spray group."
The findings, which appear in the new issue of the Archives of Otolaryngology Head & Neck Surgery, could be significant for the multitudes of people who suffer from chronic nasal and sinus conditions. In the United States, 36 million people are affected by chronic rhinosinusitis each year, and millions more are affected by other types of allergic and non-allergic rhinitis.
Treatments including antibiotics, antihistamines and anti-inflammatory drugs can be helpful, but for many patients, symptoms persist.
Treatment with saline irrigations the flushing of nasal passages with a salt water mixture often is recommended by otolaryngologists (ear, nose and throat physicians) for a variety of sinus conditions. It has long been used as a treatment following sinus surgery, and more recently is becoming common in non-surgical patients. The authors of this study say their findings suggest that otolaryngologists and primary care physicians should recommend this treatment to their patients more often.
In addition to Pynnonen, authors of the study were Dr. Jeffrey Terrell and Dr. Meredith Adams, of the Department of Otolaryngology; and H. Myra Kim, of the Department of Biostatistics and the Center for Statistical Consultation and Research at the U-M School of Public Health.
Did a relatively small number of people from Siberia who trekked across a Bering Strait land bridge some 12,000 years ago give rise to the native peoples of North and South America?
U-M scientists, working with an international team of geneticists and anthropologists, have produced new genetic evidence that's likely to hearten proponents of the land bridge theory. The study, published online in PLoS Genetics, is one of the most comprehensive analyses so far among efforts to use genetic data to shed light on the topic.
The researchers examined genetic variation at 678 key locations or markers in the DNA of present-day members of 29 Native American populations across North, Central and South America. They also analyzed data from two Siberian groups. The analysis shows:
• Genetic diversity, as well as genetic similarity to the Siberian groups, decreases the farther a native population is from the Bering Strait, adding to existing archaeological and genetic evidence that the ancestors of native North and South Americans came by the northwest route.
• A unique genetic variant is widespread in Native Americans across both American continents, suggesting the first humans in the Americas came in a single migration or multiple waves from a single source, not in waves of migrations from different sources. The researchers say the variant likely occurred shortly prior to migration to the Americas, or immediately afterward.
"We have reasonably clear genetic evidence that the most likely candidate for the source of Native American populations is somewhere in east Asia," says Noah A. Rosenberg, assistant professor of human genetics and assistant research professor of bioinformatics at the Center for Computational Medicine and Biology at the Medical School and assistant research professor at the Life Sciences Institute. Rosenberg also is an assistant professor in biostatistics at the School of Public Health and assistant professor of ecology and evolutionary biology in LSA.
Additional authors include Mattias Jakobsson, a post-doctoral fellow in human genetics at the Medical School and the Center for Computational Medicine and Biology, and Cecil Lewis Jr., former post-doctoral fellow in the Department of Human Genetics.
Quality indicator for colon cancer surgeries questioned
In a study that appeared in the Journal of the American Medical Association, researchers at the Medical School found that examining a specific number of lymph nodes after a colectomy to remove part or all of the colon is not associated with the length of patient survival.
"Hospitals vary widely in the number of lymph nodes examined.
It appears, however, that the number of lymph nodes that hospitals examined following colon resection did not influence how long patients lived," says co-author of the study, Dr. Sandra Wong, a surgical oncologist and Comprehensive Cancer Center member.
"These findings suggest that the momentum to implement a 12-node minimum as a quality indicator for hospitals performing colectomies for colon cancer should be slowed to allow for further investigation," Wong says. "Everyone is vested in improving cancer care, but at the end of the day, there are only so many resources we can use for this. If we spend a lot of resources to enact the 12-node exam as the standard of care, we're going to miss the opportunity to improve in other ways."
Wong and her colleagues also found that, regardless of how many lymph nodes hospitals examined, they tended to find the same number of nodes positive for cancer, with similar rates of chemotherapy and survival for their patients. She says there are a number of reasons that may account for this seeming paradox, including individual variations in surgical or dissection techniques. Other factors may have influence, too, including race or tumor location, leading the researchers to call for further studies that include more clinical detail.
"Lymph node counts do not identify hospitals with better results in treating colon cancer. Patients, physicians and payers need more useful quality indicators for this condition," says the study's senior author, Dr. John Birkmeyer, who directs the Michigan Surgical Collaborative for Outcomes Research and Evaluation.
The study was funded by the National Cancer Institute. Additional U-M co-authors are Hong Ji, Dr. Brent Hollenbeck, Dr. Arden Morris and Onur Baser.