Obesity and risk of motor vehicle fatal injury

Ediriweera Desapriya, Research Associate,
June 20, 2013

We recently read Rice and Zhu's [1] widely circulated article on risk of fatal injury and driver obesity. Presently, there is no consensus on the relationship between obesity and motor vehicle-related injuries and fatalities [2, 3, 4]. Indeed, some researchers have argued that obesity is a protective factor in motor vehicle-related injuries and fatalities [2, 3, 4]. The focus of Rice and Zhu study [1], therefore, was to determine if obesity is a determinant of fatality among individuals involved in motor vehicle crashes. Accordingly, Rice and Zhu [1] article attempted to fill the gap in the literature in this important area.

Although the study authors have highlighted that there is a few studies have looked at how obesity affects non-fatal and fatal injuries among vehicle occupants and this statement is not true. In fact, there is a systematic review published in this area by our research group [5]. In our systematic review we found that obesity was associated with higher fatality risk (Odds Ratio (OR) 1.89, 95% confidence interval (CI): 1.51- 2.37, P=0.0001; pooled estimate from 6 studies)[5].

Our main recommendations stem from this review were to develop interventions that address the incompatibility of standard vehicle safety design systems with obese physiques, and develop safety measures that could minimize the impact of a crash on an obese person [5]. We believe that automotive industry should move toward smart restraint systems which are calibrated for the weight and height of the particular occupant. This idea should be seriously pursued as discomfort is shown as one of the disincentives of restraint use in many countries [5].

In our systematic review we strongly proposed that future studies should be more rigorous and control for confounding factors such as obesity-related co-morbidities [5]. Unfortunately, Rice and Zhu [1] study failed to control these important confounders in their study.


(1). Rice TM, Zhu M. Driver obesity and the risk of fatal injury during traffic collisions. Emerg Med J. 2013 Jan 25. [Epub ahead of print]

(2). Zhu S, Kim JE, Ma X, Shih A, Laud PW, Pintar F, Shen W, Heymsfield SB, Allison DB. BMI and risk of serious upper body injury following motor vehicle crashes: concordance of real-world and computer- simulated observations. PLoS Med. 2010; 30;7(3):e1000250. doi: 10.1371/journal.pmed.1000250.

(3). Ryb GE, Dischinger PC. Injury severity and outcome of overweight and obese patients after vehicular trauma: a crash injury research and engineering network (CIREN) study. J Trauma. 2008;64(2):406-11. doi: 10.1097/TA.0b013e31802beff9.

(4). Mock CN, Grossman DC, Kaufman RP, Mack CD, Rivara FP. The relationship between body weight and risk of death and serious injury in motor vehicle crashes. Accid Anal Prev. 2002;34(2):221-8.

(5). Desapriya E, Giulia S, Subzwari S, Peiris DC, Turcotte K, Pike I, Sasges D, Hewapathirane DS. Does Obesity Increase the Risk of Injury or Mortality in Motor Vehicle Crashes? A Systematic Review and Meta-Analysis. Asia Pac J Public Health. 2011 Dec 20. [Epub ahead of print]

Conflict of Interest:

None declared

Conflict of Interest

None declared