Caster Semenya is about as sure a gold medal bet as there is at this year’s Olympic Games. If I had one bet to make, and my life was at stake, I’d put in on her to win the 800m. This past weekend she just missed out on the Diamond League record, running 1:56.46, at a jog. A month ago, she won the 400m, 800m and 1500m at the SA champs, all on the same day. The 400m and 800m, 50 minutes apart, were run in 50.7s and 1:58, with a second lap faster than 60 seconds, suggesting that she could go much, much faster. I watched them in Stellenbosch and have never seen anything like it. The 400m was jogged until the last 100m, and could have been under 49 seconds, and the 800m could have been run in 1:55 if it was needed.
Caster Semenya could, and should, break the 800m world record. It’s the oldest record on the tracks, held by one Jarmila Kratochvilova, and if you know anything about the sport, you know that whoever it was who broke that record was going to be faced with a few probing questions. Most of them would have been doping-related, but in the case of Semenya, thanks to the public drama that played out in 2009, they’re related to sex/gender.
Specifically, we know that Semenya was identified as having elevated testosterone levels after her gold medal in Berlin (1:55.45, as an 18-year old). We know that some intervention was applied, and we can, through pretty basic deduction, figure out that it involved lowering her testosterone levels. How? Well, at the time Semenya emerged, from nowhere, the IAAF and IOC policies on gender verification (they should call it ‘sex verification’, by the way, because sex is biological, gender is social, but anyway) were vague and unrelated to testosterone.
It was as a result of Semenya, and the absolutely disastrous handling of that situation, that the policy changed, and until last year, the policy in place said that women could compete only if their testosterone levels were below an upper limit. That upper limit, 10 nmol/L, was set up based on a study done on all the women competing in the World Championships in 2011 and 2013. The researchers took the average testosterone levels of women with a condition called Polycystic Ovary Syndrome, which was already elevated at 4.5 nmol/L, and then added 5 SD to it.
Scientists already knew that certain molecules pop up in the blood after a brain injury, including glial fibrillary acidic protein (GFAP). This protein is normally found in glial cells, which are support cells in the brain that surround nerve cells. After an injury, GFAP bursts out of the glial cells and—most importantly—easily traverses the blood-brain barrier.
While scientists are working on commercial tests for GFAP, it wasn’t clear how long this protein stays in the blood. To find out, Papa and her colleagues tracked GFAP in the blood of 584 adult volunteers who came into their emergency room within four hours of a head injury. Based on CT scans, 325 of those patients had mild to moderate concussions. Volunteers whose CT scans revealed no concussion acted as controls in the study.
The volunteers' GFAP levels were tracked at regular intervals for as long as they were in the hospital. The longest stay was seven days. Patients who had taken hits but didn't develop concussions had nearly zero GFAP in their blood during the entire length of the study. For volunteers with mild to moderate concussions, the researchers found that GFAP stuck around at high levels for the first 60 hours before trailing off. But even seven days after the injury, researchers were still able to detect slightly elevated levels of GFAP.
The paper appears in JAMA Neurology - behind their paywall
Time Course and Diagnostic Accuracy of Glial and Neuronal Blood Biomarkers GFAP and UCH-L1 in a Large Cohort of Trauma Patients With and Without Mild Traumatic Brain Injury
Linda Papa, MDCM, MSc1; Gretchen M. Brophy, PharmD2,3; Robert D. Welch, MD, MS4; Lawrence M. Lewis, MD5; Carolina F. Braga, BA1; Ciara N. Tan, BS, MHSH1; Neema J. Ameli, BS1; Marco A. Lopez, AS1; Crystal A. Haeussler, BS1; Diego I. Mendez Giordano, BS1; Salvatore Silvestri, MD1; Philip Giordano, MD1; Kurt D. Weber, MD1; Crystal Hill-Pryor, PhD6; Dallas C. Hack, MD, MPH7
1Department of Emergency Medicine, Orlando Regional Medical Center, Orlando, Florida 2Department of Pharmacotherapy and Outcomes Science, Virginia Commonwealth University, Richmond 3Department of Neurosurgery, Virginia Commonwealth University, Richmond 4Division of Emergency Medicine, Department of Medicine, Wayne State University School of Medicine, Detroit, Michigan 5Division of Emergency Medicine, Washington University School of Medicine in St Louis, Missouri 6US Department of Defense, Silver Springs, Maryland 7Brain Health, Harpers Ferry, West Virginia
Importance Glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) have been widely studied and show promise for clinical usefulness in suspected traumatic brain injury (TBI) and concussion. Understanding their diagnostic accuracy over time will help translate them into clinical practice.
Objectives To evaluate the temporal profiles of GFAP and UCH-L1 in a large cohort of trauma patients seen at the emergency department and to assess their diagnostic accuracy over time, both individually and in combination, for detecting mild to moderate TBI (MMTBI), traumatic intracranial lesions on head computed tomography (CT), and neurosurgical intervention.
Design, Setting, and Participants This prospective cohort study enrolled adult trauma patients seen at a level I trauma center from March 1, 2010, to March 5, 2014. All patients underwent rigorous screening to determine whether they had experienced an MMTBI (blunt head trauma with loss of consciousness, amnesia, or disorientation and a Glasgow Coma Scale score of 9-15). Of 3025 trauma patients assessed, 1030 met eligibility criteria for enrollment, and 446 declined participation. Initial blood samples were obtained in 584 patients enrolled within 4 hours of injury. Repeated blood sampling was conducted at 4, 8, 12, 16, 20, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156, 168, and 180 hours after injury.
Main Outcomes and Measures Diagnosis of MMTBI, presence of traumatic intracranial lesions on head CT scan, and neurosurgical intervention.
Results A total of 1831 blood samples were drawn from 584 patients (mean [SD] age, 40  years; 62.0% [362 of 584] male) over 7 days. Both GFAP and UCH-L1 were detectible within 1 hour of injury. GFAP peaked at 20 hours after injury and slowly declined over 72 hours. UCH-L1 rose rapidly and peaked at 8 hours after injury and declined rapidly over 48 hours. Over the course of 1 week, GFAP demonstrated a diagnostic range of areas under the curve for detecting MMTBI of 0.73 (95% CI, 0.69-0.77) to 0.94 (95% CI, 0.78-1.00), and UCH-L1 demonstrated a diagnostic range of 0.30 (95% CI, 0.02-0.50) to 0.67 (95% CI, 0.53-0.81). For detecting intracranial lesions on CT, the diagnostic ranges of areas under the curve were 0.80 (95% CI, 0.67-0.92) to 0.97 (95% CI, 0.93-1.00)for GFAP and 0.31 (95% CI, 0-0.63) to 0.77 (95% CI, 0.68-0.85) for UCH-L1. For distinguishing patients with and without a neurosurgical intervention, the range for GFAP was 0.91 (95% CI, 0.79-1.00) to 1.00 (95% CI, 1.00-1.00), and the range for UCH-L1 was 0.50 (95% CI, 0-1.00) to 0.92 (95% CI, 0.83-1.00).
Conclusions and Relevance GFAP performed consistently in detecting MMTBI, CT lesions, and neurosurgical intervention across 7 days. UCH-L1 performed best in the early postinjury period.
Females are often an unseen part of the concussion story even though they suffer more concussions than males, have more severe symptoms and are slower to recover. Just why is not completely clear, but the deficit in knowledge is slowly beginning to change thanks to women’s advocates behind Pink Concussions. The group gathered last weekend at Georgetown University to review the science behind concussions, and also to develop recommendations on gender-specific prevention protocols and clinical practices on how best to treat females with concussions.
In comparable sports “female rates of concussions are much higher than those of their male counterparts,” says Zachary Kerr, director of the National Collegiate Athletic Association (NCAA) Injury Surveillance Program. Over a five-year period the rates per 1000 athlete-exposures were 6.3 in females versus 3.4 in males in soccer, 6.0 in females versus 3.9 in males in basketball and 3.3 in females versus 0.9 in males in baseball and softball. Only in swimming and diving did male rates (0.3) exceed those of females (0.5). Headache, dizziness and difficulty concentrating were roughly similar among both sexes, Kerr says. But among injured high school athletes, “larger portions of females are reporting sensitivity to light, sensitivity to noise, nausea and drowsiness,” he says. They were also slower to return to normal activity.