Differences in screening and treating relative energy deficiency in sport between the United States of America and Japan.

BACKGROUND: The diagnosis and treatment of relative energy deficiency in sport (RED-S) are challenging owing to variations in symptoms and the absence of specific guidelines. This study aimed to investigate differences in the diagnosis and follow-up of RED-S, its consequences, and related factors among sports medicine physicians with different backgrounds in Japan and the USA and examine the differences between the two countries. METHODS: An anonymous survey regarding the diagnosis and treatment processes of RED-S was distributed to sports medicine physicians via email. Respondents included 58 sports medicine physicians from the USA and 241 from Japan. RESULTS: The findings showed that 77.6% of the US physicians screened athletes for RED-S, whereas 17.5% of their Japanese counterparts did so. Moreover, 98.3% and 36.7% of the US and Japanese physicians, respectively, answered that they screened athletes for eating disorders upon suspicion of low energy availability. Logistic regression analysis revealed that the number of US sports medicine physicians who screened athletes for the female athlete triad (Triad) and RED-S (odds ratio [OR] = 12.78, P<0.001) and adhered to specific criteria for athlete suspension and return-to-play (OR=33.67, P<0.01) was higher than that of their Japanese counterparts. CONCLUSIONS: The prevalence of RED-S-related screening and treatment differed between US and Japanese sports medicine physicians. Educating sports medicine physicians about the diagnosis and treatment of athletes with possible signs of RED-S is important in treating female athletes and further investigations are required to identify why the physicians screened/not screened the athletes.

Differences of Bone Mineral Density by Characteristics of Sports in Amenorrheic Athletes.

Hypothalamic amenorrhea leads to a hypoestrogenic state, causing decreased bone mineral density (BMD), while strong impact loading on bone has been shown to increase BMD. The purpose of this study is to compare BMD in female athletes based on menstrual status and their sports/events by impact loading characteristics. BMD at the lumbar spine was measured by dual-energy X-ray absorptiometry and hormone level. The subjects were classified into four groups and BMD and hormone levels were compared among the four groups, which were divided into amenorrheic athletes (AAs) and eumenorrheic athletes (EAs). This study recruited 410 female athletes (164 in the AAs and 246 in the EAs), 55 athletes in non-impact sports, 123 in low-impact sports, 141 in multidirectional sports, and 91 in high-impact sports. In the AAs group, BMD Z-score was lowest in low-impact sports (Z-score: -1.53 [-1.76, -1.30]), and was highest in high-impact sports (Z-score: 0.02 [-0.34, 0.38]). In multidirectional and high-impact sports, BMD Z-score in the AAs group did not show results lower than the average for non-athletes. When screening female athletes for low BMD, it is important to evaluate the risk of low BMD based on the impact loading characteristics of their sports/events, in addition to the menstrual state.

Real-time Monitoring of Hypoxic-Ischemic Brain Damage in Neonatal Rats Using Diffuse Light Reflectance Spectroscopy.

Obstetric management to prevent hypoxic ischemic encephalopathy (HIE) during labor is important to reduce the cerebral palsy incidence in neonates. A novel approach to monitor or predict fetal brain damage during labor is required. Diffuse reflectance spectroscopy is a noninvasive method routinely used to assess the intrinsic characteristics of tissues. This study investigated the time course of diffuse reflectance signals during an early stage of cerebral cortical damage in a neonatal rat HIE model (Vannucci's model). In the model, an HIE lesion was induced by hypoxic exposure following ligation of the left common carotid artery. Using this model, we established an experimental system to detect diffuse light reflectance signals at time points of interest. Quantitative monitoring of total hemoglobin, oxygen saturation, and scattering amplitude was conducted to examine the basis of the diffused reflectance signals. During hypoxic exposure, which induced HIE damage in the left hemisphere after ligation, the oxygen saturation level decreased, but the difference between the two hemispheres was relatively small. During this period, total hemoglobin was increased in both hemispheres, but the change in the left hemisphere was significantly greater than that in the right, which is attributable to a vigorous compensation response. During hypoxia, scattering amplitude, which reflects cellular/subcellular morphology, revealed a remarkable difference between the two hemispheres. We confirmed that scattering amplitude levels negatively correlated with the extent of edema. These findings suggest that simultaneous monitoring of the scattering amplitude, in addition to hemodynamic parameters, is useful for detecting brain tissue alterations leading to HIE.