February 1, 2017--(BRONX, NY)--Frequent soccer ball heading is a common and under recognized cause of concussion symptoms, according to a study of amateur players led by Albert Einstein College of Medicine researchers. The findings run counter to earlier soccer studies suggesting concussion injuries mainly result from inadvertent head impacts, such as collisions with other players or a goalpost. The study was published online today in Neurology®, the medical journal of the American Academy of Neurology.
"The prevailing wisdom is that routine heading in soccer is innocuous and we need only worry about players when they have unintentional head collisions," says study leader Michael L. Lipton, M.D., Ph.D., professor of radiology and of psychiatry and behavioral sciences at Einstein and director of MRI Services at Montefiore. "But our study suggests that you don't need an overt collision to warrant this type of concern. Many players who head the ball frequently are experiencing classic concussion symptoms such as headache, confusion, and dizziness during games and practice, even though they are not actually diagnosed with concussion. Concussion sufferers should avoid additional collisions or head impacts during the following days or weeks, when their risk of incurring a second concussion is extremely high. Because these injuries go unrecognized and unmanaged, there may be important clinical consequences for the short and long term."
Studies clearly show that single or repeated concussion causes neurologic problems. But little is known about the effects of frequent but lesser impacts, such as those experienced while heading a soccer ball. Some research, notably a recent study of adolescent players published in JAMA Pediatrics, suggest that heading is not a common cause of concussion. "However, these studies did not actually measure heading, and thus they were unable to separate the relative contributions of intentional and unintentional head impacts," says Dr. Lipton.
In the current study, a part of the Einstein Soccer Study, Dr. Lipton and his colleagues asked 222 adult amateur soccer players (80 percent men, ages 18 to 55) to fill out online questionnaires on their soccer-related activities during the previous two weeks, including details about heading and other unintentional head impacts and any resulting headaches, pain and dizziness as well as more severe symptoms, such as feeling dazed, needing medical attention, and becoming unconscious. Some of the 222 players filled out questionnaires for more than a single two-week span, resulting in a total of 470 questionnaires during a nine-month period in 2013-2014.
Approximately 35 percent of the participants reported one unintentional head impact, and 16 percent reported more than one such impact. The median number of headings during the two-week reporting period for all respondents was 40.5. Twenty percent of the participants reported experiencing moderate-to-very severe concussion symptoms, with 18 percent reporting severe and 7 percent very severe symptoms. Although these symptoms were more strongly connected with unintentional head impacts, heading was shown to be an independent risk factor for concussion symptoms.
"This finding is consistent with one of our previous studies, where 30 percent of soccer players who'd had more than 1,000 headings per year had a higher risk of microstructural changes in the brain's white matter, typical of traumatic brain injury, and worse cognitive performance," says Dr. Lipton
In the new study, players who headed the most were the most susceptible to concussion. "The extent to which lesser degrees of exposure to heading lead to cumulative injury over time is not known and deserves further study," Dr. Lipton says. "Our findings certainly indicate that heading is more than just a 'sub-concussive' impact, and that heading-related concussions are common. We need to give people who have these injuries proper care and make efforts to prevent multiple head impacts, which are particularly dangerous."
The study is titled, "Symptoms from Repeated Intentional and Unintentional Head Impact in Soccer Players." Other contributors are Walter F. Stewart, Ph.D., M.P.H., at Sutter Health Research, Walnut Creek, CA; Namhee Kim, Chloe Ifrah, Richard B. Lipton, M.D., Tamar Glattstein, and Mimi Kim, Sc.D., all at Einstein; and Molly E. Zimmerman, Ph.D., at Einstein and Fordham University, Bronx, NY.
The study was funded by grants from the National Institutes of Health (R01 NS082432) and the Dana Foundation. The authors declare no conflicts of interest.
About Albert Einstein College of Medicine
Albert Einstein College of Medicine is one of the nation's premier centers for research, medical education and clinical investigation. During the 2016-2017 academic year, Einstein is home to 717 M.D. students, 166 Ph.D. students, 103 students in the combined M.D./Ph.D. program, and 278 postdoctoral research fellows. The College of Medicine has more than 1,900 full-time faculty members located on the main campus and at its clinical affiliates. In 2016, Einstein received more than $160 million in awards from the National Institutes of Health (NIH). This includes the funding of major research centers at Einstein in aging, intellectual development disorders, diabetes, cancer, clinical and translational research, liver disease, and AIDS. Other areas where the College of Medicine is concentrating its efforts include developmental brain research, neuroscience, cardiac disease, and initiatives to reduce and eliminate ethnic and racial health disparities. Its partnership with Montefiore Medical Center, the University Hospital and academic medical center for Einstein, advances clinical and translational research to accelerate the pace at which new discoveries become the treatments and therapies that benefit patients. Einstein runs one of the largest residency and fellowship training programs in the medical and dental professions in the United States through Montefiore and an affiliation network involving hospitals and medical centers in the Bronx, Brooklyn and on Long Island. For more information, please visit www.einstein.yu.edi, read our blog, follow us on Twitter, like us on Facebook and view us on YouTube.