Year, Volume, Issue, Page(s):14, 95, 6, 1076-1082
Study examined the additive effect of age on disability for adults with spinal cord injury (SCI). Data regarding demographics, injury and medical characteristics, independence in activities of daily living, and psychosocial well-being were collected from participants with SCI who were enrolled in the SCI Model Systems between 1988 and 2011. The primary study outcome was the motor subscale of the Functional Independence Measure (FIM). A mixed-models approach was used to examine the additive effect of age on disability, using data for 1,660 individuals with SCI (median age at injury, 32 years) with a discharge motor FIM score and at least 1 follow-up motor FIM score. When controlling for motor FIM at discharge from rehabilitation, level and severity of injury, age at injury, sex, race, and the age-by-time interaction were not significant. Age at the time of SCI was significantly associated with motor FIM. Two sensitivity analyses found significant interactions for both age-by-time and age-by-time-square models. Trajectory of motor FIM scores is moderated slightly by age at the time of injury. The older participants were at the time of injury, the greater the curvature and the more rapid decline were found in later years. These findings indicate that age moderately influences disability for some individuals with SCI: the older the age at the time of injury, the greater the influence age has on disability.