621 FO20 – Older and younger runners, and year were risk factors for all medical encounters during a South African marathon – a safer study

Background There is a high incidence of medical encounters (MEs) and serious/life-threatening MEs in marathon road running races but injury and illness risk factors associated with MEs in these events have not been well investigated and will assist with injury and illness prevention. Objective To determine the independent risk factors that are associated with all MEs and serious/life-threatening MEs during a marathon (42.2km). Design Prospective study, with cross-sectional analyses Setting 2014–2019 Cape Town Marathon Participants 40446 race starters Assessment of Risk Factors All MEs and a subgroup of serious/life-threatening MEs were recorded for six years and also reported by organ system affected. The following possible risk factors associated with MEs were explored: sex, age, year (as a proxy for environmental and route changes) and race pace (data only available on the finishers). Main Outcome Measurements The incidence (I, per 1000 starters) of MEs and serious/life-threatening MEs, and independent risk factors (Prevalence ratios [PR]) associated with all MEs and serious/life-threatening MEs affected. Results The overall incidence for all MEs was 8.7 (95%CI:7.8–9.6) per 1000 starters, and 1.0 (95%CI:0.7–1.4) per 1000 starters for serious/life-threatening MEs. The significant risk factors identified for all MEs were: younger (<30=10.7/1000 starters) and older age (>50=12.6/1000 starters) (<30 vs 31–40: PR=1.4; <30 vs 41–50: PR=1.5; 31–40 vs >50: PR=0.6; 41–50 vs >50: PR=0.6; p=0.0003), and year 2014 (PR=1.7; p=0.0125), 2015 (PR=2.1; p=0.0001) and 2017 (PR=2.2; p<0.001) were significantly higher than 2019. WBGT was lowest in 2019, and highest in 2015/2017, which relates similarly to the year variable for ME data. Sex and race pace were not significantly associated, nor a sex/year interaction. No significant associations for serious/life-threatening were found. Conclusions Younger and older athletes, and year (as a proxy for environmental factors, as well as route changes) were associated with an increase in MEs during a marathon.