Avalanche Fatalities in the United States: A Change in Demographics.

Objective: To describe demographic patterns in avalanche fatalities in the United States during the past 6 decades according to geographic location and preavalanche activity.

Methods: The Colorado Avalanche Information Center currently manages the National Avalanche Accident Dataset. This dataset describes deidentified avalanche fatalities beginning in 1951. Covariates included age, sex, month, state of occurrence, and preavalanche activity. Both absolute and proportional avalanche fatalities were calculated by year and by each covariate. A linear regression model was used to trend the proportion of avalanche fatalities stratified by covariate.

Results: There were 925 recorded avalanche fatalities in the United States between 1951 and 2013. There were an average of 15 ± 11 fatalities/y (mean ± SD; range, 0 to 40 fatalities/y). The mean (+/- SD) age was 29 ± 6.6 years (range, 6-67 years), and 86% were men. Total avalanche fatalities have increased linearly (R(2) = 0.68). Despite the highest number of total deaths in Colorado (n = 253), the proportion of avalanche fatalities in Colorado decreased (-5% deaths/decade; P = .01). Snowmobilers are now the largest group among fatalities and accounted for 23% of deaths (n = 213). The proportion of snowmobile fatalities has increased (+7% deaths/decade; P < .01), as has the proportion of snowboarder fatalities (+2% deaths/decade; P < .01).

Conclusions: Avalanche fatalities have increased. This is most likely related to an overall rise in backcountry utilization. Fatalities have increased among snowmobilers and snowboarders. Despite a rise in backcountry utilization, avalanche fatalities in Colorado are decreasing. A strategy of focused training and education aimed toward at-risk groups could result in lower avalanche fatalities.