Objective: To determine the body composition and bone stiffness in patients with stable chronic obstructive pulmonary disease (COPD), and to explore the association between them.
Methods: Ninety-four male COPD patients in stable conditions and 47 healthy smokers were recruited from March 2013 to January 2014.Lung function, body composition and bone stiffness were measured.In COPD patients, the symptoms were assessed by COPD Assessment Test (CAT) and Modified British Medical Research Council (mMRC) respectively, and the acute exacerbation and hospitalization history in the previous 12 months were also recorded.
Results: The prevalence of muscle atrophy (FFMI<16 kg/m(2) ) and high risk of bone fracture (T<-1) were 24.5% and 72.3% respectively in stable male COPD patients. The patients with muscle atrophy, had lower FEV1%pred (39.0 ± 15.2) vs (50.1 ± 16.2), frequent acute exacerbations [1.0(0-3.0) vs 0 (0-1.0)] and lower bone stiffness index (75.5 ± 13.3) vs (85.5 ± 15.7), (test values were 2.904, -1.476, 2.728, all P < 0.05). Compared with patients with low risk of bone fracture(T ≥ -1), patients with high risk of bone fracture (T<-1) showed higher mMRC score [2.0(1.0-3.0) vs 1.0(0-2.0)] (Z = -2.297, P < 0.05). The FFMI correlated positively with SI (r = 0.294, P = 0.004) in COPD patients.
Conclusions: Patients with stable COPD presented worse lung function and increased risk of future exacerbations when combined with muscle atrophy and high risk of bone fracture, and the two co-morbidities were correlated and should be assessed.