老年学と老年医学の研究

概要

Why Elderly Patients with Ground Level Falls Die Within 30 Days And Beyond?

Alicia Mangram*, James Dzandu, Gervork Harootunian, Nicholas Zhou, Jacqueline Sohn, Michael Corneille, Patrick O Neill, Scott Petersen, Olakunle F Oguntodu and William G Johnson

Background: Together with a growing geriatric population in the United States, ground level falls (GLF) are troubling and quickly becoming a significant cause for geriatric trauma deaths. This study describes the factors associated with GLF fall deaths and examines how these factors changed mortality rate over a 3-year follow-up. Methods: A retrospective study was conducted based on the ASU Center of Health Information and Research (CHiR) database. The dataset included 52,391 patients with GLF admissions at 4 Level-I trauma centers in Arizona from 2008-2011. Patients were identified using ICD-9 GLF specific E-codes E885.x to E888.x. 49,138 patients <60 years who had non-ground level falls were excluded. Abstracted patient demographics, injury characteristics, cause and post injury time of death were summarized and compared using non-parametric tests, Student’s t-test, ANOVA, univariate and multivariate regression methods as appropriate; p≤.05 was considered statistically significant. Results: There were 3,251 patients with GLF who were followed during the 3-year study period. The majority was white (85.7%), female (57.8%), and 36.1% were in the 8th decade of life. Most patients fell at home (71.5%) and suffered medium severity injuries (median ISS= 9). The Trauma Revised Injury Severity Score (TRISS) was 0.93 and mean Charlson Comorbidity Index (CCI) was 0.63. The mortality rate (31.1%) over the 3-year period was remarkably high despite the fact that GLF is often considered a low-energy mechanism of injury. We identified the following significant, non-modifiable and independent risk factors for 1-30 day post-injury mortality: age ≥80 years, male gender, ISS≥16, AIS head ≥4, AIS extremities >2, TRISS <0.63, CCI ≥0.67, and ICU LOS >2. Conclusion: GLF although considered a low-energy mechanism of injury, is fast becoming a significant cause of mortality among the elderly, beginning immediately after the injury, through intermediate and longer-term follow-up periods. Mortality outcomes were modified only by the unalterable effects of chronic conditions such as cardiac diseases, stroke, cancer, diabetes or liver diseases in subsequent years. We recommend trauma level 1 activation for all elderly patients who suffer GLF with concerns for head injury and emphasis on aggressive head injury management strategies to mitigate GLF-related deaths.