Skeletal muscle adiposity and outcomes in candidates for lung transplantation: a lung transplant body composition cohort study

Abstract

CT measurement of body composition may improve lung transplant candidate selection. We assessed whether skeletal muscle adipose deposition on abdominal and thigh CT scans was associated with 6 min walk distance (6MWD) and wait-list survival in lung transplant candidates. Each ½-SD decrease in abdominal muscle attenuation (indicating greater lipid content) was associated with 14 m decrease in 6MWD (95% CI -20 to -8) and 20% increased risk of death or delisting (95% CI 10% to 40%). Each ½-standard deviation decrease in thigh muscle attenuation was associated with 15 m decrease in 6MWD (95% CI -21 to -10). CT imaging may improve candidate risk stratification.

Keywords: clinical epidemiology; imaging/CT MRI etc; lung transplantation.

Figure 1

Association between 6 min walk distance and (A) mean thigh muscle attenuation, (B) mean abdominal muscle attenuation, (C) thigh intramuscular adipose tissue index and (D) body mass index. Black line represents the mixed-effects linear model with median values for covariates (sex, forced vital capacity, diagnosis and age) and centre as random effect. Models A–C are additionally adjusted for muscle index (area/height²). Surrounding grey areas represent 95% confidence bands. Vertical lines along the x-axis each represent a single study subjects.