Impact of hospital type on risk-adjusted, traffic-related 30-day mortality: a population-based registry study

Abstract

Background: Traffic incidents are still a major contributor to hospital admissions and trauma-related mortality. The aim of this nationwide study was to examine risk-adjusted traffic injury mortality to determine whether hospital type was an independent survival factor. Methods: Data on all patients admitted to Swedish hospitals with traffic-related injuries, based on International Classification of Diseases codes, between 2001 and 2011 were extracted from the Swedish inpatient and cause of death registries. Using the binary outcome measure of death or survival, data were analysed using logistic regression, adjusting for age, sex, comorbidity, severity of injury and hospital type. The severity of injury was established using the International Classification of Diseases Injury Severity Score (ICISS). Results: The final study population consisted of 152,693 hospital admissions. Young individuals (0–25 years of age) were overrepresented, accounting for 41% of traffic-related injuries. Men were overrepresented in all age categories. Fatalities at university hospitals had the lowest mean (SD) ICISS 0.68 (0.19). Regional and county hospitals had mean ICISS 0.75 (0.15) and 0.77 (0.15), respectively, for fatal traffic incidents. The crude overall mortality in the study population was 1193, with a mean ICISS 0.72 (0.17). Fatalities at university hospitals had the lowest mean ICISS 0.68 (0.19). Regional and county hospitals had mean ICISS 0.75 (0.15) and 0.77 (0.15), respectively, for fatal traffic incidents. When regional and county hospitals were merged into one group and its risk-adjusted mortality compared with university hospitals, no significant difference was found. A comparison between hospital groups with the most severely injured patients (ICISS ≤0.85) also did not show a significant difference (odds ratio, 1.13; 95% confidence interval, 0.97–1.32). Conclusions: This study shows that, in Sweden, the type of hospital does not influence risk adjusted traffic related mortality, where the most severely injured patients are transported to the university hospitals and centralization of treatment is common.

Keywords

Epidemiological / International classification of diseases injury severity score / Injury / Risk-adjusted mortality / Trauma

References

[1] Trafa. Road traffic injuries. 2014. Available at: https://www.trafa.se/globalassets/statistik/vagtrafik/vagtrafikskador/2009-2015/2014/vaegtrafikskador_2014.pdf. Accessed 12 Sep 2019.

[2] Trafikverket. Analys av trafiksäkerhetsutvecklingen 2019: Trafikverket. Available at: https://trafikverket.ineko.se/Files/en-US/60919/Ineko.Product.RelatedFiles/2019_090_analys_av_trafiksakerhetsutvecklingen_2018_2.pdf. Accessed 12 Sep 2019.

[3] Larsen R, Backstrom D, Fredrikson M, Steinvall I, Gedeborg R, Sjoberg F. Decreased risk adjusted 30-day mortality for hospital admitted injuries: a multi-centre longitudinal study. Scand J Trauma Resusc Emerg Med. 2018. doi: 10.1186/s13049-018-0485-2.

[4] Evans L. Traffic fatality reductions: United States compared with 25 other countries. Am J Public Health. 2014; 104: 1501-7.

[5] Larsen R, Backstrom D, Fredrikson M, Steinvall I, Gedeborg R, Sjoberg F. Female risk-adjusted survival advantage after injuries caused by falls, traffic or assault: a nationwide 11-year study. Scand J Trauma Resusc Emerg Med. 2019. doi: 10.1186/s13049-019-0597-3.

[6] Demetriades D, Martin M, Salim A, Rhee P, Brown C, Chan L.The effect of trauma center designation and trauma volume on outcome in specific severe injuries. Ann Surg. 2005; 242: 512-7.

[7] Nathens AB, Jurkovich GJ, Maier RV, Grossman DC, MacKenzie EJ, Moore M, et al. Relationship between trauma center volume and outcomes. JAMA. 2001; 285: 1164-71.

[8] Ala-Kokko TI, Ohtonen P, Koskenkari J, Laurila JJ. Improved outcome after trauma care in university-level intensive care units. Acta Anaesthesiol Scand. 2009; 53(10): 1251-6.

[9] Statistiska centralbyrån (SCB).Folkmängd i riket, län och kommuner 30 juni 2019 och befolkningsförändringar 1 januari-30 juni 2019. Available at: https://www.scb.se/hitta-statistik/statistik-efter-amne/befolkning/befolkningens-sammansattning/befolkningsstatistik/pong/tabell-och-diagram/kvartals--och-halvarsstatistik--kommun-lan-och-riket/forsta-halvaret-2019. Accessed 12 Sep 2019.

[10] Gedeborg R, Warner M, Chen LH, Gulliver P, Cryer C, Robitaille Y et al. Internationally comparable diagnosis-specific survival probabilities for calculation of the ICD-10-based injury severity score. J Trauma Acute Care Surg. 2014; 76: 358-65.

[11] Gedeborg R, Chen LH, Thiblin I, Byberg L, Melhus H, Michaelsson K et al. Prehospital injury deaths-strengthening the case for prevention: nationwide cohort study. J Trauma Acute Care Surg. 2012; 72: 765-72.

[12] Candefjord S, Buendia R, Caragounis EC, Sjoqvist BA, Fagerlind H. Prehospital transportation decisions for patients sustaining major trauma in road traffic crashes in Sweden. Traffic Inj Prev. 2016; 17: 16-20.

[13] Fagerlind H, Harvey L, Candefjord S, Davidsson J, Brown J. Does injury pattern among major road trauma patients influence prehospital transport decisions regardless of the distance to the nearest trauma centre?-a retrospective study. Scand J Trauma Resusc Emerg Med. 2019. doi: 10.1186/s13049-019-0593-7.

[14] MacKenzie EJ, Rivara FP, Jurkovich GJ, Nathens AB, Frey KP, Egleston BL et al. A national evaluation of the effect of trauma-center care on mortality. N Engl J Med. 2006; 354: 366-78.

[15] Celso B, Tepas J, Langland-Orban B, Pracht E, Papa L, Lottenberg L et al. A systematic review and meta-analysis comparing outcome of severely injured patients treated in trauma centers following the establishment of trauma systems. J Trauma 2006; 60: 371-8.

[16] Swedish PeriOperative Registry (SPOR).Sjukhus anslutna till SPOR: SPOR. 2019. Available at: https://www.spor.se/spor/anslutna-kliniker/#tab-id-1. Accessed 18 Apr 2019.

[17] Stephenson S, Henley G, Harrison JE, Langley JD. Diagnosis based injury severity scaling: investigation of a method using Australian and New Zealand hospitalisations. Inj Prev. 2004; 10: 379-83.

[18] Ashley DW, Pracht EE, Medeiros RS, Atkins EV, NeSmith EG, Johns TJ et al. An analysis of the effectiveness of a state trauma system: treatment at designated trauma centers is associated with an increased probability of survival. J Trauma Acute Care Surg. 2015; 78: 706-12.

[19] Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987; 40: 373-83.

[20] Christensen S, Johansen MB, Christiansen CF, Jensen R, Lemeshow S. Comparison of Charlson comorbidity index with SAPS and APACHE scores for prediction of mortality following intensive care. Clin Epidemiol. 2011; 3: 203-11.

[21] OECD E.Young Drivers: The Road to Safety. 2006. https://www.oecd.org/itf/37556934.pdf. Accessed 16 Sep 2019.

[22] Turner C, McClure R. Age and gender differences in risk-taking behaviour as an explanation for high incidence of motor vehicle crashes as a driver in young males. Inj Control Saf Promot. 2003; 10: 123-30.

[23] Thornton J. WHO report shows that women outlive men worldwide. BMJ. 2019. doi: 10.1136/bmj.l1631.

[24] Falk B. Do drivers become less risk-prone after answering a questionnaire on risky driving behaviour? Accid Anal Prev. 2010; 42: 235-44.

[25] Ortega HW, Velden HV, Krause E, Reid S. Traumatic deaths in children: is there a difference between urban and rural populations? Pediatr Emerg Care. 2013; 29: 36-8.

[26] Ludvigsson JF, Andersson E, Ekbom A, Feychting M, Kim JL, Reuterwall C et al. External review and validation of the Swedish national inpatient register. BMC Public Health. 2011. doi: 10.1186/1471-2458-11-450.

[27] Miyamoto K, Shibata N, Nakashima T, Kato S. Prehospital quick sequential organ failure assessment as a tool to predict in-hospital mortality. Am J Emerg Med. 2018; 36: 1832-6.

[28] Jawa RS, Vosswinkel JA, McCormack JE, Huang EC, Thode HC Jr, Shapiro MJ et al. Risk assessment of the blunt trauma victim: the role of the quick sequential organ failure assessment score (qSOFA). Am J Surg. 2017; 214: 397-401.