Research Letter
February 21, 2024
Electric Bicycle Injuries and Hospitalizations
Adrian M. Fernandez, Kevin D. Li, Hiren V. Patel, et al
JAMA Surg. 2024;159(5):586-588.
doi:10.1001/jamasurg.2023.7860
Electric bicycles (e-bicycles) are a popular consumer choice in the clean transportation revolution. Imports of e-bicycles topped 1.1 million in 2022 compared with 437 000 in 2020.1 We examined e-bicycle injuries and hospitalizations in the US from 2017 to 2022.
Methods
This cross-sectional study used data from the National Electronic Injury Surveillance System (NEISS), which provides estimates of patients with injuries presenting to US emergency departments. We queried NEISS for e-bicycle injuries (codes 5035 and 3215 and keywords electronic, electric, electrical, bike, bicycle, e-bike, e-bicycle, ebike, ebicycle, e bike, e bicycle, power, powered) between 2017 and 2022, excluding injuries from traditional bicycles, mopeds, motor bikes, electric scooters, and minibikes. Injury narratives were reviewed to identify helmet use. Narratives without mention of helmet status were excluded from helmet-related calculations. The NEISS complex sampling design was used to obtain US population projections of emergency department visits and hospitalizations. Stratified, weighted, nested, and year-adjusted estimates were calculated using the R survey package, version 4.3.1 (R Project for Statistical Computing). Estimates were log transformed and modeled using linear regression. We applied survey-weighted logistic regression to assess changes in injury patterns and odds of head injury. Helmet use between sexes was compared using the χ2 test with Rao-Scott second-order correction. A 2-sided P < .05 was considered significant. The study was exempt from institutional review board review according to the Common Rule, as the data used were public and deidentified.
Results
From 2017 to 2022, a weighted estimated total of 45 586 (95% CI, 17 079-74 094) e-bicycle injuries occurred in the US (1038 NEISS cases), leading to an estimated 5462 hospitalizations (95% CI, 2148-8777; 143 NEISS cases) (Table 1). There was a 30-fold rise in e-bicycle injuries (>99% annually; P < .001) and a 43-fold increase in hospitalizations (>108% annually; P < .001). Injuries in children increased from 0% to 13% of total injuries, while injuries in young adults aged 18 to 34 years decreased from 63% to 30% of total injuries (Table 2). The incidence of head trauma from e-bicycle accidents in 2022 was approximately 49 times higher than in 2017, increasing from approximately 163 (95% CI, 0-370) to approximately 7922 (95% CI, 4136-11 708) head injuries, a growth rate that outpaced overall e-bicycle injuries (Table 2). Odds of helmet use decreased by 5.6% each year (P = .01). Helmets were worn by 44% (6095 of 13 914) of injured e-bicyclists, at similar rates in men and women (44% vs 43%, P = .92). The odds of sustaining a head injury for nonhelmeted e-bicyclists were 1.9 times higher (95% CI, 1.25-2.84; P = .005) compared with those using helmets.
Discussion
We found that health care use associated with e-bicycle injuries has surged in the US. This trend started in the early 2000s as e-bicycles emerged on the market2 and mirrors increasing health care use related to pedal-powered bicycles and electric scooters.3,4
This study corroborates prior findings that soft tissue injuries and fractures predominate among adult e-bicyclists.2 However, the increasing proportion of head injuries in our study warrants further examination, as traumatic brain injuries are more severe in e-bicyclists than in traditional bicyclists.5
The decrease in helmet use may be associated with increasing head injuries. Only 44% of injured e-bicyclists wore helmets, with proportionally fewer wearing helmets each year. Although helmet use by e-bicyclists varies worldwide, Swiss studies report helmet use as high as 69%.5 E-bicycle ride-sharing companies may not include helmets given rider preference and logistical challenges (accessibility, cost, hygiene, or safety concerns).
Study limitations include lack of detailed clinical information with each report. The incidence of e-bicycle–related injuries may be underestimated, as injured individuals may not seek medical care or may visit physicians outside the emergency department.
E-bicycle ridership may grow in the US as Congress considers extending the Inflation Reduction Act tax credits offered to electric car purchasers to e-bicycle buyers.6 The safety profiles of e-bicycles should be studied to promote a safe e-bicycle infrastructure and riding practices.
