PT - JOURNAL ARTICLE AU - Coby van de Bool AU - Harry Gosker AU - Bram van den Borst AU - Celine Op den Kamp AU - Ilse Slot AU - Annemie Schols TI - Quadriceps muscle fibre type shift is more pronounced in sarcopenic patients with COPD DP - 2014 Sep 01 TA - European Respiratory Journal PG - P4488 VI - 44 IP - Suppl 58 4099 - http://erj.ersjournals.com/content/44/Suppl_58/P4488.short 4100 - http://erj.ersjournals.com/content/44/Suppl_58/P4488.full SO - Eur Respir J2014 Sep 01; 44 AB - BackgroundQuadriceps muscle in COPD is characterized by a loss of oxidative phenotype which adversely affects exercise performance. We recently showed in a large cohort of patients eligible for rehabilitation that sarcopenia in COPD not only is associated with muscle strength but also with cycle exercise endurance. We hypothesize that the loss of oxidative muscle fibres is more pronounced in COPD patients with sarcopenia, which in turn could accelerate muscle wasting.AimTo investigate quadriceps muscle fibre type composition in relation to sarcopenia in patients with COPD and in healthy controls.MethodsBody composition was assessed by Dual-energy X-ray Absorptiometry in 49 COPD patients (FEV1 52±17%, age 66±7y) and 53 healthy controls (FEV1 112±17%, age 63±6y). Sarcopenia was defined as appendicular skeletal muscle mass-index (SMI) <7.23 kg/m2 for males and <5.67 kg/m2 for females. Muscle fibre type and cross sectional area (CSA) were assessed in quadriceps muscle biopsies.ResultsSarcopenia was present in 6% of healthy controls versus 31% of COPD patients (P<0.001). COPD patients showed a 33% lower proportion of oxidative type I fibres (P<0.001) and 10% lower CSA of type IIx fibre than healthy controls (P<0.01). Sarcopenic patients showed a 33% lower proportion (P<0.05) as well as a 27% lower CSA of type I fibres (P<0.05) compared to non-sarcopenic patients.ConclusionThe more pronounced decreased type I fibre proportion in sarcopenic COPD patients suggests a cross-talk between muscle mass and oxidative phenotype regulation.This study was financially supported by the by the Lung Foundation Netherlands (grant number: 3.4.09.003).