Non-obese | Obese | p-value | |
Subjects n | 37 | 47 | |
Age years | 70.0±7.9 | 68.1±6.9 | 0.23 |
Male sex | 57 | 60 | 0.80 |
Race | |||
Caucasian | 92 | 85 | 0.40 |
Black/African American | 8 | 11 | |
Other | 0 | 4 | |
Education | |||
Less than high school | 16 | 23 | 0.19 |
High school | 19 | 21 | |
Some college | 38 | 28 | |
Bachelor's degree | 16 | 9 | |
At least some graduate school | 11 | 19 | |
Smoking history pack-years | 65±32 | 50±24 | 0.02 |
FEV1 % predicted | 51±18 | 55±16 | 0.30 |
Body mass index kg·m−2 | 25±3 | 35±4 | 0.00 |
Atopic | 22 | 36 | 0.17 |
Disease severity (GOLD stage) | |||
II | 35 | 53 | 0.07 |
III | 43 | 40 | |
IV | 22 | 6 | |
Respiratory health status | |||
Chronic bronchitis reported in ATS-DLD | 41 | 40 | 0.99 |
Emphysema reported in ATS-DLD | 73 | 55 | 0.10 |
SGRQ# | 35±17 | 43±18 | 0.03 |
mMRC¶ | 2.4±1.0 | 2.6±1.2 | 0.28 |
Nocturnal symptoms | 14 | 36 | 0.02 |
ED/hospitalisation within past year | 14 | 23 | 0.25 |
Serum biomarkers | |||
White blood cell count cells·mm−3 | 7891±2532 | 7326±2229 | 0.29 |
Neutrophil count cells·mm−3 | 4890±2008 | 4226±1449 | 0.09 |
Eosinophil count cells·mm−3 | 2.5±1.6 | 3.2±2.4 | 0.16 |
Fibrinogen mg·dL−1 | 437±88 | 444±116 | 0.79 |
C-reactive protein ng·mL−1 | 4.6±4.9 | 7.6±18.6 | 0.34 |
IL-6 pg·mL−1 | 2.3±2.7 | 2.5±3.0 | 0.73 |
IL-8 pg·mL−1 | 8.7±3.4 | 10.3±6.5 | 0.18 |
Exhaled nitric oxide | 15.3±11.3 | 20.7±13.4 | 0.06 |
Comorbidities | |||
Diabetes mellitus | 11 | 30 | 0.04 |
Obstructive sleep apnoea | 16 | 32 | 0.10 |
Myocardial infarction | 5 | 19 | 0.06 |
Stroke | 8 | 13 | 0.49 |
Congestive heart failure | 3 | 9 | 0.26 |
Baseline medication use | |||
Short-acting β-agonist | 43 | 49 | 0.60 |
LABA | 6 | 6 | 0.88 |
ICS | 11 | 17 | 0.40 |
ICS/LABA | 49 | 51 | 0.83 |
Anticholinergic | 51 | 47 | 0.68 |
Environmental characteristics | |||
Indoor PM2.5 µg·m−3 | 8.0 (4.3–15.1) | 9.1 (5.4–14.9) | 0.48 |
Indoor PM2.5−10 µg·m−3 | 4.2 (2.9–6.8) | 4.6 (3.3–7.2) | 0.52 |
Time spent indoors h | 22.1±0.2 | 21.8±0.2 | 0.27 |
Data are presented as mean±sd, % or median (interquartile range), unless otherwise stated. N=84. FEV1: forced expiratory volume in 1 s; GOLD: Global Initiative for Chronic Obstructive Lung Disease; ATS-DLD: American Thoracic Society-Division of Lung Disease questionnaire; SGRQ: St George's Respiratory Questionnaire; mMRC: modified Medical Research Council; ED: emergency department; IL: interleukin; LABA: long-acting β-agonist; ICS: inhaled corticosteroid; PM2.5: particulate matter with an aerodynamic size ≤2.5 μm; PM2.5−10: particulate matter with an aerodynamic size 2.5–10 μm. #: scale 0–100, higher score indicates more limitations; ¶: scale 0–4; higher score indicates more dyspnoea.