Sarcopenia is Associated with Frailty in Lung Transplant Candidates

PURPOSE Frailty is associated with mortality in lung transplantation (LT). Sarcopenia is considered a cardinal component of frailty; this relationship has not previously been evaluated in lung disease. METHODS In a multicenter prospective cohort of 367 LT candidates, 3 sarcopenia definitions were tested: European Working Group on Sarcopenia in Older People (EWGSOP), Foundation for the National Institutes of Health (FNIH) Sarcopenia Project, and the lowest quartile of gender-specific appendicular skeletal muscle (ASM) mass index (see Table Footer for definitions). ASM mass was measured by bioelectrical impedance. Frailty measures included Short Physical Performance Battery (SPPB; range 0-12; SPPB ≤7=frail) and the Fried Frailty Phenotype (FFP; range 0-5; FFP ≥3=frail). Associations between sarcopenia definitions and frailty were tested by logistic regression, adjusting for age, sex, and diagnosis. Generalized additive models (GAMs) tested non-linear associations between ASM mass index and frailty, adjusting for age and sex. RESULTS Sarcopenia prevalence was 13% by EWGSOP and 12% by FNIH. Frailty prevalence was 17% for SPPB and 30% for FFP. Sarcopenia was associated with higher risk of SPPB and FFP frailty by EWGSOP, but not by FNIH. By lowest quartile of ASM mass index, sarcopenia was associated with FFP frailty (Table). The relationship between ASM mass index and risk of SPPB/FFP frailty appeared to be linear (Figure). CONCLUSION Sarcopenia is associated with frailty in LT candidates by EWGSOP and ASM mass index lowest quartile definitions. Future studies should optimize sarcopenia definitions and determine if reducing sarcopenia improves LT outcomes.