Injury patterns and outcomes in late middle age (55-65): The intersecting comorbidity with high-risk activity - A retrospective cohort study.

Background: Late middle age (LMA), is a watershed between youth and old age, with unique physical and social changes and declines in vitality, but a desire to remain active despite increasing comorbidity. While post-injury outcomes in the elderly are well studied, little is known regarding LMA patients. We analyzed the injured LMA population admitted to a rural, regional Level 1 Trauma Center relative to outcomes for both younger and older patients.

Materials And Methods: Our registry was queried retrospectively for patients admitted 7/2008- 12/2015; they were divided into three cohorts: 18-54, 55-65, and >65 years. Demographics, injury details, comorbidities, and outcomes were compiled and compared using ANOVA and Chi-square; p < 0.05 was significant.

Results: During the study period, 10,543 were admitted; 1419 (14%) were LMA who experienced overall injury mechanisms, severities and patterns that mirrored the younger cohort. However comorbidity rates were high (56.4%) and comparable to the elderly. LMA patients had the highest rates of alcohol abuse, morbid obesity, and psychiatric illness (p < 0.0001) and suffered the poorest outcomes: highest complications and hospital charges, and longest ICU and hospital LOS. LMA mortality (4.1%) was 41% higher than younger patients (2.9%; p < 0.02) and similar to the older cohort (4.7%; p = 0.32).

Conclusions: The LMA population has similar mechanisms and injury patterns to younger patients, while exhibiting comorbidity rates similar to the elderly. High-energy injuries exact a greater toll in LMA with poorer outcomes and greater resource utilization. Targeted outreach for injury prevention, and future studies, are needed to address high-risk behavior, substance abuse, and societal contributors.