Epidemiology and Severity of Medical Events for Mountain Bikers and Hikers Transported by Ambulance in Western Australia, 2015 to 2020.

INTRODUCTION: Outdoor activities offer physical and mental health benefits. However, incidents can occur requiring ambulance transport to hospital. This study aimed to describe the epidemiology and severity of traumatic and medical incidents for mountain bikers and hikers transported by ambulance within Western Australia.

METHODS: This was a retrospective cohort study of ambulance-transported mountain bikers and hikers within Western Australia from 2015 to 2020. Data were extracted from ambulance electronic patient care records. Multivariable analyses were undertaken to identify variables associated with higher patient severity based on the National Early Warning Score 2 (NEWS2).

RESULTS: A total of 610 patients required ambulance transport to hospital while mountain biking (n=329; 54%) or hiking (n = 281; 46%). Median age of mountain bikers and hikers was 38 (24-48) y and 49 (32-63) y, respectively. Paramedics reported a fracture in 92 (28%) mountain bikers and 78 (28%) hikers. The predominant injury locations for mountain bikers were upper limbs and for hikers, lower limbs. Cases were trauma related in 92% of mountain bikers and 55% of hikers. A significant association ( P <0.001) between the etiology of the ambulance callout and patient severity was found. In trauma etiology cases, the frequency of medium-risk+ NEWS2 severity was 21.4%. In medical cases, the frequency of medium-risk+ severity was 40.8%.

CONCLUSION: Both mountain bikers and hikers experienced incidents requiring ambulance transport to hospital. Incidents of a medical etiology had a higher clinical risk, as determined by the NEWS2 scores, regardless of activity being undertaken.