Incidence of Sports-Related Traumatic Brain Injury of All Severities: A Systematic Review

Introduction: Whilst there are many benefits to participating in sports and recreational activities, there is also a risk of injury including sports-related traumatic brain injury ­(SR-TBI). To inform injury prevention initiatives, it is important to explore the burden of SR-TBI at the population level. This review aimed to estimate the incidence of SR-TBI in the general population across injury severities. Methods: Systematic search of electronic databases using keywords from 1965 until June 2019 facilitated by hand searches of reference lists. Original research reporting on the incidence of SR-TBI, capturing people of all ages in a well-defined population area was included. Studies were excluded if they focused on a specific sport(s) or population group. All studies were required to be published in the English language. Quality of studies was determined as poor, moderate or good based on the standards of reporting of neurological disorders criteria. Data on year(s) of data collection, diagnostic criterion, case ascertainment sources, population denominator and incidence per 100,000 and by age, sex, injury severity and sport were extracted by 2 authors independently using a standard data extraction form. Results: Following review of 11 studies meeting the inclusion criteria, the incidence of SR-TBI within hospital-based studies ranged between 3.5 and 31.5 per 100,000. One community-based study using multiple case ascertainment sources identified a higher incidence of 170 per 100,000. SR-TBI accounted for 1.2–30.3% of all TBIs. One study provided incidence data across a 5-year period suggesting an increasing trend in incidence over time. Males were more at risk than females (66.1–75.6%), and adolescents and young adults had the highest incidence of SR-TBI. Conclusion: The primary objective of this review was to provide a summary of descriptive data on SR-TBI epidemiology at the population level. SR-TBI represented up to one-third of all causes of TBI. Trends in incidence by age and sport were challenging to determine due to lack of consistency in reporting as well as the small number of studies overall. Undertaking injury surveillance at all levels of TBI will assist with understanding the nature, mechanism of and surrounding events where injuries occur in sport.