Defining the "older" crash victim: the relationship between age and serious injury in motor vehicle crashes.
OBJECTIVE
Age is often used as a predictor of injury and mortality in motor vehicle crashes (MVCs), however, the age that defines an "older" occupant in terms of injury-risk remains unclear, as do specific injury patterns associated with increasing age. The objective of this study was to evaluate the relationship between age and serious injury (including injury patterns) for occupants involved in MVCs.


METHODS
This was a retrospective cohort study using a national population-based cohort of adult front-seat occupants involved in MVCs and included in the National Automotive Sampling System Crashworthiness Data System database from 1995 to 2006. The primary outcome was serious injury, defined as an abbreviated injury scale (AIS) score >/=3 in any body region. Anatomic injury patterns were also assessed by age.


RESULTS
One hundred thousand one hundred and fifty-six adult front-seat occupants were included in the analysis, of which 14,128 (2%) were seriously injured. Age was a strong predictor of serious injury using a variety of different age covariates (categorical, continuous, and polynomial) in multivariable regression models (p<0.0001 for all). There was evidence of a strong non-linear relationship between age and serious injury (p<0.001 for comparison of non-linear to linear representation of age). There was no age that clearly defined an "older" occupant by injury risk, as the odds of injury increased with increasing age across all age groups. The proportion of serious head and extremity injuries gradually increased with increasing age, while serious chest injuries markedly increased after 60 years.


CONCLUSIONS
Age is a strong predictor of serious injury from motor vehicle trauma, the risk of which increases in non-linear fashion as age increases. There is no specific age that clearly defines an "older" occupant by injury risk.
Newgard
Craig D
CD
Center for Policy and Research in Emergency Medicine, Department of Emergency Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA. newgardc@ohsu.edu
D000063:Accidents, Traffic / Q000401:mortality / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D015599:Trauma Severity Indices; D014481:United States / Q000453:epidemiology; D014947:Wounds and Injuries / Q000209:etiology* / Q000401:mortality