Dorsal muscle group area and surgical outcomes in liver transplantation

Abstract

INTRODUCTION Better measures of liver transplant risk stratification are needed. Our previous work noted a strong relationship between psoas muscle area and survival following liver transplantation. The dorsal muscle group is easier to measure but it is unclear if they are also correlated with surgical outcomes. METHODS Our study population included liver transplant recipients with a preoperative CT scan. Cross-sectional areas of the dorsal muscle group at the T12 vertebral level were measured. The primary outcomes for this study were 1 and 5-year mortality and 1-year complications. The relationship between dorsal muscle group area and post-transplantation outcome was assessed using univariate and multivariate techniques. RESULTS Dorsal muscle group area measurements were strongly associated with psoas area (r = 0.72; p < 0.001). Postoperative outcome was observed from 325 patients. Multivariate logistic regression revealed dorsal muscle group area to be a significant predictor of 1-year mortality (odds ratio [OR] = 0.53, p = 0.001,) and 5-year mortality (OR = 0.53, p < 0.001), and 1-year complications (OR = 0.67, p = 0.007). CONCLUSION Larger dorsal muscle group muscle size is associated with improved post-transplantation outcomes. The muscle is easier to measure and may represent a clinically relevant postoperative risk factor.

Systematic Review and Meta-Analysis of the Impact of Computed Tomography–Assessed Skeletal Muscle Mass on Outcome in Patients Awaiting or Undergoing Liver Transplantation

“…From these 28 records, eight studies assessed muscle mass with means other than CT and one study was performed in a population other than patients awaiting or undergoing liver transplantation. The remaining 19 studies, including 3803 patients in partly overlapping cohorts, were included in this systematic review (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Cross-referencing yielded no additional records.…”

“…The methods of muscle measurement and sarcopenia definitions that were used are summarized in Table 2. Nine studies reported the cross-sectional muscle area with corresponding skeletal muscle index (12)(13)(14)17,(22)(23)(24)(25)30), whereas the psoas area was reported in eight studies (15,16,18,19,21,(26)(27)(28) and the dorsal muscle group area was reported in one study (20). One study calculated the morphometric age (calculated with total psoas area, psoas density, and abdominal aortic calcifications) (29).…”

“…The mean skeletal muscle index ranged from 43.0 to 54.3 cm²/m² (13,30). The prevalence of sarcopenia was reported in 17 studies (12)(13)(14)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)30) and ranged from 22.2% (30) to nearly 70% (13). The prevalence greatly depended on the definition used.…”

“…In the 11 studies that investigated the association between skeletal muscle mass and posttransplantation survival, seven described an association (13,14,16,18,20,21,29), and three gave no association (17,24,27,28). All details about median survival times, yearly survival rates, and the association between skeletal muscle mass and overall survival are summarized in Table 4.…”

“…In both studies reporting overall posttransplantation complications, low skeletal muscle mass was associated with an increased risk of postoperative complications (Table 5) (20,28). The study of Lee et al showed that an increase in both the total psoas area and the dorsal muscle group with 1 standard deviation was associated with an increased risk of complications within 1 year after transplantation (OR 0.48, 95% CI 0.32-0.72, p < 0.001, and OR 0.67, 95% CI 0.50-0.90, p = 0.007, per standard deviation increase in dorsal muscle group area) (20).…”