Monday Bits and Bytes: What Imaging Tells Us About Exercise
According to findings presented by researchers today at RSNA, a little light exercise could go a long way toward preventing osteoarthritis. Researchers used MRI to evaluate the impact of various levels of exercise on 132 participants at risk for developing knee osteoarthritis; they found that light exercise was the most beneficial to knee cartilage, with no exercise contributing to increased weight while heavy exercise contributed to degenerated collagen architecture. "People can reduce their risk for osteoarthritis by maintaining a healthy weight and avoiding risky activities and strenuous exercise," said study author Keegan Hovis, BS, RN, of UCSF's department of radiology. "Lower-impact sports, such as walking, swimming, or using an elliptical trainer are likely more beneficial than high-impact sports, such as running or tennis." That being said, if running is your thing, the following may be of interest. In a two-month study using mobile MRI, researchers followed runners for two months to see how their bodies responded to the stress of a 4,500 km race -- the TransEurope FootRace 2009, to be exact, which started in southern Italy and ended in Norway. Twenty-two runners had an MRI every three or four days during the 64-day race, allowing researchers to evaluate stress-induced changes in whole-body volume, body fat, skeletal muscle, cartilage and more. The results showed a surprising degree of muscle volume loss in the leg, but also indicated that there are some injuries one can "run through," such as intermuscular inflammation. "The rule that 'if there is pain, you should stop running' is not always correct," noted study author Uwe Schultz, MD, of University Hospital of Ulm in Germany. In even further exercise news, research out of the University of Pittsburgh indicates that walking can slow the progression of Alzheimer's disease in both healthy adults and those with mild cognitive impairment. In a 20-year study of the relationship between physical activity and brain structure in 426 people using 3D MRI to identify changes in brain volume, researchers found that five miles of walking a week increased brain volumes in the cognitively impaired, while six miles a week did the same for healthy adults. "Walking is not a cure," said Cyrus Raji, PhD, of UPMC's department of radiology. "But walking can improve your brain's resistance to the disease and reduce memory loss over time." In other news presented today at the show, researchers from University of Washington Medical Center suggest that women with a history of breast cancer be screened annually with MRI. In a retrospective review of initial screening breast MRI examinations of 1,026 women over five years, the cancer yield in women with a history of the disease was double that of women with genetic or family history -- i.e., women for whom MRI screening is already recommended. Additionally, "women with a personal history were less likely to be recalled for additional testing and less likely to have a biopsy for a false positive MRI finding," said study author Wendy DeMartini, MD, of UWMC's radiology department. Finally, new research indicates that waiting for a diagnosis can be more anxiety-inducing in patients than disease itself. Studying the stress levels of 214 women scheduled to undergo different diagnostic and treatment procedures, researchers found that breast biopsy patients reported significantly higher levels of anxiety than patients undergoing chemoembolization. "These results really drive home the point that the distress of not knowing your diagnosis is serious," said lead author Elvira Lang, MD, of Harvard Medical School. "We believe that health care providers and patients are not fully aware of this and may downplay the emotional toll of having a diagnostic exam."