Purpose: The current study will attempt to elucidate whether frailty has a role in motor vehicle crash injury causation.
Methods: The association between frailty and injury was studied among Crash Injury Research Engineering Network (CIREN) cases. The baseline “physical functioning” (PF) score of the SF-36 was used as a marker of frailty (i.e., PF score <75). Frailty associations with ISS and occupant, vehicular and crash factors were explored. Frailty association with delta V was analyzed among injured (i.e., brain, rib, or femur) belted occupants in frontal crashes to establish whether frailty confers a different risk of each particular injury.
Results: Frailty occurred in 13.7 % of the cohort (n=1,747). Median (q1-q3) ISS was 14.0 (10-22) among the frail and 17.0 (10-24) among the non frail (p=0.40). Frailty was significantly associated with advanced age, male gender, the presence of co-morbidities, extreme BMIs, frontal and near-side crashes and delta V < 45 km/h. Seat belt use and ISS<16 were not associated with frailty. Multiple linear regressions, adjusting for age, gender and BMI revealed a negative association between frailty and log delta V (coefficient -0.188, p=0.04) among those with rib fractures but not among those with brain injuries or femur fractures.
Conclusion: PF score, a marker of frailty, is associated with similar ISS and lower delta V and is independently linked to lower delta V thresholds for some injuries (i.e. rib fractures) but not for others (i.e. brain injuries and femur fractures). These associations suggest a potential role of frailty in injury causation.
|2010||Andersen D, Ryb G, Dischinger P, Kufera J, Read K. Self-reported health indicators in the year following a motor vehicle crash: a comparison of younger versus older subjects. In: 54th Annual Proceedings, Association for the Advancement of Automotive Medicine (AAAM). October 17-20, 2010; Las Vegas, NV.359-366.|
|1998||The Abbreviated Injury Scale-1990 Revision, Update 1998. Des Plaines, IL: Association for the Advancement of Automotive Medicine (AAAM); 1998.|
|1992||Ware JE Jr, Sherbourne CD. The MOS 36-item short-form health survey (SF-36), I: conceptual framework and item selection. Med Care. June 1992;30(6):473-483.|
|2008||Bose D, Crandall JR. Influence of active muscle contribution on the injury response of restrained car occupants. In: 52nd Annual Proceedings, Association for the Advancement of Automotive Medicine (AAAM). October 6-8, 2008; San Diego, CA.61-71.|
|2010||Bose D, Crandall JR, Untaroiu CD, Maslen EH. Influence of pre-collision occupant parameters on injury outcome in a frontal collision. Accid Anal Prev. July 2010;42(4):1398-1407.|