oa Drivers obesity and road crash risks in the United States

We assessed obesity trends in US drivers involved in fatal crashes since 1999 and distinguished whether crash risk factors were different between obese and non-obese drivers. We included drivers of passenger cars involved in fatal traffic crashes between January 1, 1999 and December 31, 2012. Obesity was classified according to the World Health Organization guidelines and profiled between 1999 and 2012 using adjusted prevalence ratio (aPR) from log-binomial regression models. Differences in crash risks (e.g., fatality, drunk-driving, seat-belt non-use) between obese and non-obese drivers were estimated as adjusted odds ratio (aOR) using logistic regression models. A total of 753,024 US drivers were involved in fatal crashes, of whom obesity information was available in 534,887. About 56% (n=299,078) were driving passenger cars. The prevalence of class I obesity increased from 10% in 1999 to 14% in 2012 (aPR=1.50, 95% confidence intervals [95%CI]=1.42-1.58), class II obesity from 3% to 5% (aPR=2.22, 95%CI=2.05-3.01), and class III obesity from 1% to 2% (aPR=2.65; 95%CI=2.27-3.10). Compared to non-obese controls, obese drivers had significantly higher risks for fatality (1.10≤aOR≤1.47), seat-belt non-use (1.00≤aOR≤1.21), need for extrication (1.01≤aOR≤1.23), and ambulance transport time ≥30min (1.01≤aOR≤1.28). Compared to non-obese controls, obese drivers were less likely to drink-drive (0.41≤aOR≤0.72) and speed ≥65mph (0.78≤aOR≤0.93).. The rising national prevalence of obesity extends to US drivers involved in fatal crashes and indicates the need to improve seat-belt use, vehicle design, and post-crash care for this vulnerable population.