Recent Changes in the Epidemiology of Second Impact Syndrome: A Review of Trends, Risk Factors, and Prevention Strategies

Abstract

Background: Second Impact Syndrome (SIS) is a rare but life-threatening condition that occurs when a second traumatic brain injury (TBI) is sustained before complete recovery from an initial concussion. It primarily affects young athletes and individuals in high-risk environments such as military training. Recent advancements in concussion management have influenced the epidemiology of SIS, affecting its incidence, demographic trends, and risk factors. Objective: This study aims to review the recent changes in SIS epidemiology, analyze the impact of emerging diagnostic and prevention strategies, and discuss ongoing challenges in concussion management. Methods: A systematic review of recent literature was conducted, analyzing epidemiological data, policy changes, and advancements in concussion diagnosis and management from 2015 to 2024. Data were obtained from peer-reviewed journals, sports injury registries, and health organization reports. Results: Findings indicate a decline in SIS cases in sports settings due to improved concussion protocols, but challenges persist in non-sports-related environments such as military settings. Increased awareness, stricter return-to-play policies, and advancements in concussion assessment tools have contributed to this trend. However, gaps remain in early detection and compliance with safety guidelines. Conclusion: While SIS incidence appears to be decreasing in regulated sports environments, continued efforts in education, policy enforcement, and research into neuroprotective strategies are necessary to prevent SIS in all at-risk populations.

Keywords: Second Impact Syndrome, traumatic brain injury, concussion, epidemiology, return-to-play policies, sports injuries, military TBI