The Impact of a Comorbid Spinal Cord Injury on Cognitive Outcomes of Male and Female Patients with Traumatic Brain Injury

Abstract

Introduction Evidence of the effect of comorbid spinal cord injury (SCI) on cognitive outcomes in persons undergoing rehabilitation following newly diagnosed traumatic brain injury (TBI) is limited. We conducted a population‐based study to investigate this effect. Objective To compare cognitive outcomes in patients with TBI with and without a comorbid SCI. Setting/Participants Adult patients diagnosed with TBI were identified and followed for 1 year through provincial health administrative data; those who entered inpatient rehabilitation were studied. Design A retrospective matched cohort study using the National Rehabilitation Reporting System data of all acute care and freestanding rehabilitation hospitals in Ontario, Canada. Main Measures The exposure was a comorbid SCI in patients with diagnosed TBI. Exposed patients were matched to unexposed (TBI‐only) on sex, age, injury severity, and income, in a ratio of one to two. Gain differences in the cognitive subscale of the Functional Independence Measure were compared between exposed and unexposed patients using multivariable mixed linear model, controlling for comorbidity propensity score, gains in motor function, and rehabilitation care indicators. Results Over the first year post injury, 12 750 (0.84%) of all TBI patients entered inpatient rehabilitation, of whom 1359 (10.66%) had a comorbid SCI. A total of 1195 exposed patients (65.4% male, mean age 50.9 ± 20.6 for male and 61.8 ± 21.8 for female patients) were matched to 2390 unexposed patients. Controlling for confounding, exposed patients had lower cognitive gain (beta −0.43; 95% CI −0.72, −0.15), for both male (beta −0.39; 95% CI −0.75, −0.03) and female (beta −0.51; 95% CI −0.97, −0.05) patients. The adverse effects of comorbid SCI were driven largely by lower gains in problem solving and comprehension. Conclusions Adult patients with TBI and comorbid SCI showed a lower cognitive domain response to inpatient rehabilitation than patients with TBI alone. Identifying patients at risk for worse cognitive outcomes may facilitate the development of targeted strategies that improve cognitive outcomes.

Dual diagnosis of TBI and SCI: an epidemiological study in the pediatric population

“…According to the 2011 National Spinal Cord Injury Statistical Center, Birmingham, Alabama data, the ratio of males to females in the SCI population alone is approximately 4:1 ( 28 ). There is limited data on the ratio of males to females in the DD population, with one study finding approximately a 1.8:1 M:F ratio ( 12 ). While males comprise the majority in both the adult and pediatric SCI and DD population, in the pediatric population, the gap between the genders is narrowed.…”

“…In a single-center study, 31.6% of children with SCI had a concomitant brain injury ( 10 ). Other retrospective studies evaluating DD among patients with SCI who received inpatient rehabilitation excluded individuals under the age of 18 ( 8 , 11 , 12 ).…”

“…Prior studies have demonstrated that adults with DD are more likely to require transfer from acute inpatient rehabilitation facilities to acute care facilities, more likely to suffer severe medical complications, and less likely to be discharged home as compared to those with SCI alone ( 11 , 13 ). When compared to those with isolated TBI, adults with comorbid SCI demonstrate lower gains in cognitive domains during their courses of inpatient rehabilitation, particularly with problem solving and comprehension ( 12 ). When compared to adults with SCI without co-morbid TBI, those with DD are discharged from inpatient rehabilitation with greater cognitive impairment and having achieved less improvement in their motor Functional Independence Measure (FIM ™ ) scores ( 14 ).…”

Neurologic Outcome Prediction in the Intensive Care Unit

“…In penetrating injuries, outlining the areas of the nervous system that are affected, the caliber of bullet, and whether retained fragments are present can be helpful. Every traumatic brain injury harbors potential for associated systemic, neurovascular, and spinal injuries, 24 which also impact recovery trajectories. Even in isolated brain injuries, patterns of injury portend different trajectories: patients with associated intraventricular hemorrhage and mass effect are less likely to regain consciousness during rehabilitation 10 .…”

“…The elements of this proposed neuroprognostication framework are depicted in FIGURE 10-1. FIGURE 10-2, 20-22 FIGURE 10-3, [23][24][25][26][27][28][29][30][31] and FIGURE 10-4 [32][33][34][35][36][37][38] summarize factors relevant to outcome prediction specific to hypoxic-ischemic brain injury, TBI, and subarachnoid hemorrhage, respectively. Similar factors also impact prognosis in acute ischemic stroke and intracerebral hemorrhage, along with the overall volume and anatomic location of injured tissue.…”