The effect of age on functional outcome in mild traumatic brain injury: 6-month report of a prospective multicenter trial.
OBJECTIVE
Elderly patients (aged 60 years and older) have been demonstrated to have an increased mortality after isolated traumatic brain injury (TBI); however, the prognosis of those patients surviving their hospitalization is unknown. We hypothesized that surviving elderly patients would also have decreased functional outcome, and this study examined the functional outcome of patients with isolated TBI at discharge and at 6 months posthospitalization.


METHODS
This was a multicenter prospective study of all patients with isolated moderate to severe TBI defined as Head Abbreviated Injury Scale score of 3 with an Abbreviated Injury Scale score in any other body area of 1. Patients surviving to discharge gave their consent and were enrolled. Data collected included demographics, Glasgow Coma Scale (GCS) score at admission, and neurosurgical interventions. Outcome data included discharge disposition and Glasgow Outcome Scale score and modified Functional Independence Measure (FIM) score at discharge and at 6 months.


RESULTS
Two hundred thirty-five patients were enrolled, with 44 (19%) aged greater than or equal to 65 years. Mechanisms of injury were falls (34%), assaults (28%), motor vehicle collisions (14%), pedestrian (11%), and other (12%). Falls were more common in the older patients and assaults in the younger group. The mean admitting GCS score was 12.8 (95% confidence interval [CI], 12.4-13.3), with older patients having a higher mean GCS score, 14.1 (95% CI, 13.6-14.6) versus 12.5 (95% CI, 12.0-13.1; p = 0.03). There were no differences in the percentage of patients admitted to the intensive care unit or requiring neurosurgical intervention between younger and older patients. Because there were few elderly patients with low GCS scores who survived to discharge, outcome measures focused on those patients with GCS scores of 13 to 15. A greater percentage of elderly were discharged to rehabilitation (28% vs. 16%, p =0.08). The mean discharge FIM score was 10.4 (95% CI, 9.8-11.0) for the elderly versus 11.4 (95% CI, 11.1-11.7) for the young (p =0.001), with 68% elderly and 89% young discharged with total independent scores of 11 to 12. At 6 months, the difference narrowed, but the mean FIM score was still greater for the young group, 11.7 (95% CI, 11.6-11.9) versus 11.0 (95% CI, 10.6-11.4; p < 0.001).


CONCLUSIONS
Functional outcome after isolated mild TBI as measured by the Glasgow Outcome Scale and modified FIM is generally good to excellent for both elderly and younger patients. Older patients required more inpatient rehabilitation and lagged behind their younger counterparts but continued to recover and improve after discharge. Although there were statistically significant differences in the FIM score at both discharge and 6 months, the clinical importance of these small differences in the mean FIM score to the patient's quality of life is less clear. Measurable improvement in functional status during the first 6 months after injury is observed in both groups. Aggressive management and care of older patients with TBI is warranted, and efforts should be made to decrease inpatient mortality. Continued follow-up is ongoing to determine whether these outcomes persist at 12 months.
Mosenthal
Anne C
AC
Department of Surgery, New Jersey Trauma Center, University of Medicine and Dentistry of New Jersey-New Jersey, Medical School, Newark, New Jersey, USA. mosentac@umdnj.edu
Livingston
David H
DH
Lavery
Robert F
RF
Knudson
Margaret M
MM
Lee
Seong
S
Morabito
Diane
D
Manley
Geoffrey T
GT
Nathens
Avery
A
Jurkovich
Gregory
G
Hoyt
David B
DB
Coimbra
Raul
R
D015998:Abbreviated Injury Scale; D000058:Accidental Falls / Q000706:statistics & numerical data; D000063:Accidents, Traffic / Q000706:statistics & numerical data; D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D001930:Brain Injuries / Q000209:etiology / Q000401:mortality / Q000534:rehabilitation; D002140:California / Q000453:epidemiology; D005260:Female; D015577:Geriatric Assessment; D015600:Glasgow Coma Scale; D006801:Humans; D008297:Male; D008875:Middle Aged; D009515:New Jersey / Q000453:epidemiology; D010351:Patient Discharge / Q000706:statistics & numerical data; D011379:Prognosis; D011446:Prospective Studies; D020127:Recovery of Function; D016019:Survival Analysis; D014193:Trauma Centers; D016896:Treatment Outcome; D014754:Violence / Q000706:statistics & numerical data; D014861:Washington / Q000453:epidemiology