A Comprehensive Analysis of the Association of Psoas and Masseter Muscles with Traumatic Brain Injury Using Computed Tomography Anthropometry

Abstract

Objective : Psoas and masseter muscles are known markers of sarcopenia. However, the relative superiority of either muscle as a marker is unclear. Therefore, this study analyzed the two muscles in patients with a prognosis of traumatic brain injury (TBI). Methods : Patients with TBI visiting a regional trauma center between January 2017 and December 2018 were selected, and their medical records were reviewed. TBI patients with an abbreviated injury score (AIS) of 4 or 5 were selected. Patients with an AIS of 4 or 5 at the chest, abdomen, and extremity were excluded. Patients with a hospital stay of 1 to 2 days were excluded. Both muscle areas were measured based on the initial computed tomography. The psoas muscle index (PMI) and the masseter muscle index (MMI) were calculated by dividing both muscle areas by height in meters squared (cm 2 /m 2 ). These muscle parameters along with other medical information were used to analyze mortality and the Glasgow outcome scale (GOS). Results : A total of 179 patients, including 147 males (82.1%), were analyzed statistically. The mean patient age was 58.0 years. The mortality rate was 16.8% (30 patients). The mean GOS score was 3.7. Analysis was performed to identify the parameters associated with mortality, which was a qualitative study outcome. The psoas muscle area (16.9 vs. 14.4 cm 2 , p=0.028) and PMI (5.9 vs. 5.1 cm 2 /m 2 , p=0.004) showed statistical differences between the groups. The PMI was also statistically significant as a risk factor for mortality in logistic regression analysis (p=0.023; odds ratio, 0.715; 95% confidence interval, 0.535-0.954). Quantitative analyses were performed with the GOS scores. Bivariate correlation analysis showed a statistically significant correlation between PMI and GOS scores (correlation coefficient, 0.168; p=0.003). PMI (p=0.004, variation inflation factor 1.001) was significant in multiple regression analysis. The masseter muscle area and MMI did not show significance in the study. Conclusion : Larger PMI was associated with statistically significant improved survival and GOS scores, indicating its performance as a superior prognostic marker. Further analyses involving a larger number of patients, additional parameters, and more precise settings would yield a better understanding of sarcopenia and TBI.

Feasibility of using cross-sectional area of masticatory muscles to predict sarcopenia in healthy aging subjects

“…Some authors found an association between low masseter mass and mortality in elderly patients after trauma 17 – 19 . In contrast, others did not confirm the prognostic relevance of the masseter for the same clinical condition 20 , 21 . CT-assessed low masseter mass has also been linked to postoperative pneumonia in oesophageal cancer 22 , carotid endarterectomy 23 , 24 , and stroke outcome 25 .…”

Computed tomography measured epicardial adipose tissue and psoas muscle attenuation: new biomarkers to predict major adverse cardiac events and mortality in patients with heart disease and critically ill patients. Part II: Psoas muscle area and density

“…It was found that PMI was statistically significant as a risk factor for mortality (P = 0.023; OR = 0.715). A statistically significant correlation was found between PMI and Glasgow Outcome Scale (GOS) score (correlation coefficient, 0.168; P = 0.003) [66]. Supplemental Table 2 lists the studies searching for associations between PMI and other CT-measured anthropomorphic variables and outcomes in trauma patients.…”

The associations of psoas and masseter muscles with sarcopenia and related adverse outcomes in older trauma patients: a retrospective study

“…It has been used to predict outcomes in carotid endarterectomies [8,9] and strokes [10]. Specific to trauma, 4 studies have looked into masseter area measurements as a prognostic parameter [11][12][13][14]. In 2016, Wallace et al introduced the role of the masseter as a sarcopenia surrogate in a large retrospective cohort study in trauma patients aged above 65 years [11].…”

“…Masseter sarcopenia in severe traumatic brain injury has also been shown to be predictive of 30-day mortality and the need for longer-term acute facilities or rehabilitation on discharge [12]. However, a recent Korean study involving patients with traumatic brain injury of all ages negated statistical prognostic value of masseter measurements, but supported the correlation of psoas measurements with mortality and Glasgow outcome score [14].…”