Association of body-mass index to circumference of body and limbs, inspiratory capacity, and inflammatory biomarker in emphysematous patients

Although emphysema primarily affects the lungs, it also has systemic manifestations. Low body mass index (BMI) is a poor prognostic indicator in patients with emphysema. Low BMI, reduced quadriceps muscle mass and elevated inflammatory biomarker may present in emphysema. This study aims to investigate whether BMI is related to airflow limitation, exercise capacity and inflammatory biomarker. Twenty-eight patients with clinically stable emphysema were evaluated for BMI, circumference of chest, abdomen, quadriceps muscle and upper arm, and right upper arm muscle power, airway obstruction, inspiratory capacity (IC), distance of 6-min walking distance (6MWD), oxygen saturation, and serum inflammatory biomarkers [C-reactive protein (CRP), TNF-a and IL-6]. BMI was significantly associated with circumference of chest (r = 0.716, p <0.01), abdomen(r = 0.783, p <0.01), quadriceps muscle (r = 0.565, p <0.01) and upper arm (r = 0.712, p <0.01), IC (r = 0.451, p <0.05), muscle power of right upper arm (r = 0.490, p <0.01) and oxygen saturation (r = 0.380, p <0.05). However, the levels of CRP (1467 ± 202 ug/ml) and IL-6 (8.5 ± 4.2 pg/ml) in emphysematous patients (n = 10) with lower BMI (<21 kg/m²) were significantly higher than those (CRP (911 ± 130 ug/ml, p <0.05) and IL-6 (2.1 ± 0.5 pg/ml, p <0.05)) of patients (n = 18) with higher BMI (>21 kg/m²). BMI associated circumference of limbs, inspiratory capacity, and inflammatory biomarker in emphysematous patients.