Beating the weekend trend: increased mortality in older adult traumatic brain injury (TBI) patients admitted on weekends

Abstract

Background: Weekend admission is associated with mortality in cardiovascular emergencies and stroke but the effect of weekend admission for trauma is not well defined. We sought to determine whether differences in mortality outcomes existed for older adults with substantial head trauma admitted on a weekday versus over the weekend.

Methods: Data from the 2006, 2007, and 2008 Nationwide Inpatient Sample were combined and head trauma admissions were isolated. Abbreviated injury scale (AIS) scores were calculated using ICDMAP-90 Software. Individuals aged 65 to 89 y with head AIS equal to 3 or 4 and no other region score <3 were included. Individual Charlson comorbidity scores were calculated and individuals with missing mortality, sex, or insurance data were excluded. Wilcoxon rank sum and Student t-tests compared demographics, length of stay, and total charges for weekday versus weekend admissions. The χ2 tests compared sex and head injury severity. Logistic regression modeled mortality adjusting for age, sex, injury severity, comorbidity, and insurance status.

Results: Of the 38,675 patients meeting criteria, 9937 (25.6%) were admitted on weekends. Mean age was similar (78.4 versus 78.4, P = 0.796) but more weekend admissions were female (51.6% versus 50.2%, P = 0.022). Weekend patients demonstrated slightly lower comorbidity (mean Charlson = 1.07 versus 1.14, P < 0.001) and head injury severity (58.3% versus 60.8% AIS = 4, P < 0.001). Median weekend length of stay was shorter (4 versus 5 d, P < 0.001). Weekend and weekday median total charges did not differ ($27,128 versus $27,703, respectively, P = 0.667). Proportional mortality was higher among weekend patients (9.3% versus 8.4%, P = 0.008). After adjustment, weekend patients demonstrated 14% increased odds of mortality (OR 1.14, 95% CI 1.05-1.23).

Conclusion: Older adults with substantial head trauma admitted on weekends are less severely injured, carry less comorbidity, and generate similar total charges compared with those admitted on weekdays. However, after accounting for known risk confounders, weekend patients demonstrated 14% greater odds of mortality. Mechanisms behind this disparity must be determined and eliminated.