Investigation on the Relationship between Metabolic Changes and Symptom Burden in Sport-Related Concussion Recovery

Abstract

Background: A sport-related concussion (SRC) is a mild traumatic brain injury resulting from impulsive forces in sports, often presenting various symptoms. Clinicians lack objective measures and rely on subjective patient reports (via symptom checklists or inventories) to guide return-toplay decisions. These methods, however, may not reflect physiologic recovery, with concern over the under-reporting of symptoms to return to activity quicker. Quantitative tracking of physiologic recovery could offer a more personalized approach to treating concussion. Following concussion, neurometabolic events unfold impacting neuronic membranes and disrupting ionic balance. Sodiumpotassium pumps increase, boosting ATP production but depleting glucose as well leading to an inability to utilize glucose effectively. During this period alternative energy substrates may be used potentially including ketone bodies. Acetone, a ketone body that is produced when the main ketone body is broken down to be used for energy, is small and able to be exhaled in the breath and measured non-invasively. Tracking the altered metabolism and understanding how those changes affect symptomology could offer a quantitative measure useful for clinicians. This study, part of the BrACKS initiative, aims to explore breath acetone as a marker for concussion recovery, assessing its association with symptom severity and number. Methods:In this cross-sectional study six collegiate athletes from a single Division I university including (N = 5) football players, and (N = 1) soccer player diagnosed with a SRC during their competitive season were recruited for the study. Breath acetone was measured in parts per million by portable breathalyzer and symptoms measured by the Sport Concussion Assessment Tool (SCAT-5) daily until participants were 14 days post-concussion or cleared to return to activity. Statistical assessments evaluating the dependency of breath acetone on symptom measures, exploring the relationship between daily changes in breath acetone and symptom measures, and determining how larger or smaller changes in symptoms affect breath acetone.Results: Breath acetone exhibited individualized patterns like symptom severity and number. No significant association was found between breath acetone and symptom severity or number, but a significant associative relationship was observed in daily changes between breath acetone and symptom number. Conclusion:While breath acetone did not show a direct association with symptom burden, the study suggests potential for quantitative biomarkers to complement traditional symptom tracking. Further longitudinal research with larger cohorts is essential for understanding this relationship and making recommendations.