Abdominal fat mass contributes to the systemic inflammation in chronic obstructive pulmonary disease

BACK GROUND & AIMS: Altered body composition in chronic obstructive pulmonary disease (COPD) is often reflected by muscle wasting, while only few studies have focused on abdominal fat mass. The contribution of abdominal fat mass to the systemic inflammation often present in COPD has not been examined yet. The aim of the present study was to investigate if abdominal fat mass contributes to the systemic inflammation in patients with moderate to severe COPD.

Methods: Muscle wasting (fat free mass index <17.1 kg/m(2) for men and 14.6 kg/m(2) for women) and abdominal fat mass (android/gynoid %fat mass >1.0 for men and >0.8 for women) were assessed by dual-energy X-ray absorptiometry in 295 patients with moderate to severe COPD (175 men). Plasma C-reactive protein (CRP) concentration was analysed by high sensitive (HS)-ELISA.

Results: Diffusion capacity was higher in patients with abdominal obesity. In addition, fat mass index was a significant determinant for plasma CRP concentration. In a subgroup of patients with CRP<5 mg/l (n=168), CRP was positively associated with abdominal fat mass. In addition, a significant proportion of abdominal obese patients had muscle wasting, and CRP levels were higher in these patients compared to the patients without abdominal obesity.

Conclusion: Abdominal fat mass contributes to the systemic inflammation in COPD. This study provides further evidence for systemic phenotyping of patients with COPD incorporating besides markers of muscle mass also markers of abdominal obesity.