Table 1.
Subject demographics, lung function, symptom scores, imaging parameters, blood and sputum measurements
| Variables | Healthy | S-COPD | NS-COPD (Biomass smoke) | NS-COPD (Occupational)a | S-COPD Vs. BS-COPD | S-COPD Vs. NS-COPD (Occupational) | BS-COPD Vs. NS-COPD (Occupational) |
|---|---|---|---|---|---|---|---|
| Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | ||||
| N | 118 | 79 | 59 | 34 | |||
| Sex (M: F) | 53%: 47% | 100%: 0% | 0%: 100% | 100%: 0% | |||
| Age (Years) | 64.4 ± 7.8 | 67.2 ± 7.4 | 62.4 ± 7.3 | 66.7 ± 8.1 | < 0.0001 | p = ns | 0.010 |
| BMI (kg/m2) | 21.9 ± 3.8 | 19.3 ± 3.4 | 21.3 ± 4.4 | 20.0 ± 3.3 | 0.002 | p = ns | p = ns |
| Spirometry | |||||||
| FEV1 Pre (% Predicted) | 99.4 ± 14.7 | 43.1 ± 17.8 | 39.9 ± 12.4 | 41.9 ± 14.4 | p = ns | p = ns | p = ns |
| FVC Pre (% Predicted) | 102.1 ± 16.8 | 63.6 ± 20.5 | 57.9 ± 16.04 | 62.6 ± 19.2 | 0.005 | 0.732 | 0.032 |
| Δ Reversibility FEV1 Absolute (mL) | 40.0 ± 93 | 160.0 ± 154.0 | 160 ± 130 | 170 ± 190 | p = ns | p = ns | p = ns |
| Δ Reversibility FEV1% | 2.2 ± 4.9 | 19.0 ± 19.9 | 25.6 ± 24.1 | 19.3 ± 20.6 | p = ns | p = ns | p = ns |
| Δ Reversibility FVC Absolute (mL) | 0.0 ± 190.0 | 237.0 ± 312.0 | 240 ± 230 | 290 ± 300 | p = ns | p = ns | p = ns |
| Δ Reversibility FVC % | 0.3 ± 7.4 | 15.5 ± 22.6 | 23.2 ± 31.5 | 18.2 ± 22.2 | p = ns | p = ns | p = ns |
| FEV1/FVC Post bronchodilator (%) | 80.5 ± 6.1 | 53.1 ± 10.9 | 56.4 ± 8.2 | 52.8 ± 9.9 | 0.045 | p = ns | 0.051 |
| PEF (% Predicted) | 89.2 ± 16.0 | 34.5 ± 15.8 | 29.8 ± 11.2 | 34.9 ± 24.3 | p = ns | p = ns | p = ns |
| FEF25–75 Pre % Predicted | 65.7 ± 24.4 | 15.3 ± 7.4 | 12.8 ± 6.9 | 14.8 ± 7.4 | p = ns | p = ns | p = ns |
| Plethysmography | |||||||
| TLC Pre (% Predicted) | 84.2 ± 15.9 | 104.1 ± 23.1 | 99.8 ± 32.6 | 103.2 ± 27.3 | p = ns | p = ns | p = ns |
| RV Pre (% Predicted) | 98.8 ± 26.4 | 180.8 ± 65.09 | 176.2 ± 72.1 | 174.2 ± 59.6 | p = ns | p = ns | p = ns |
| IC Pre (% Predicted) | 75.2 ± 27.3 | 49.6 ± 18.7 | 49.8 ± 23.7 | 43.7 ± 19.3 | p = ns | p = ns | p = ns |
| RV/TLC Pre (% Predicted) | 116.8 ± 21.4 | 171.5 ± 29.7 | 170.9 ± 39.4 | 175.7 ± 31.2 | p = ns | p = ns | p = ns |
| SGaw Pre (% Predicted) | 159.6 ± 78.0 | 36.2 ± 21.0 | 24.5 ± 13.6 | 26.9 ± 16.3 | 0.010 | p = ns | p = ns |
| IOS | |||||||
| R5 (kPa s L−1) Pre (% Predicted) | 148 ± 74.8 | 231.8 ± 96.4 | 287.3 ± 100.1 | 244.2 ± 93.5 | 0.005 | p = ns | p = ns |
| R20 (kPa s L− 1) Pre (% Predicted) | 118.0 ± 50.6 | 130.1 ± 44.6 | 158.3 ± 51.2 | 134.6 ± 47.1 | 0.012 | p = ns | p = ns |
| R5-R20 (kPa s L− 1) Pre | 0.16 ± 0.1 | 0.36 ± 0.2 | 0.60 ± 0.3 | 0.39 ± 0.2 | < 0.0001 | p = ns | 0.003 |
| X5 Pre (kPa s L− 1) | −0.24 ± 0.2 | − 0.56 ± 0.3 | −0.9 ± 0.4 | −0.7 ± 0.3 | < 0.0001 | p = ns | p = ns |
| Ax Pre (Hz kPa s L− 1) | 1.96 ± 2.0 | 5.59 ± 3.5 | 10.3 ± 5.7 | 7.1 ± 3.7 | < 0.0001 | p = ns | 0.034 |
| RF Pre (Hz) | 22.4 ± 6.9 | 33.4 ± 7.5 | 37.2 ± 7.4 | 38.1 ± 10.0 | 0.022 | 0.041 | p = ns |
| Gas Diffusion | |||||||
| DLCo % Predicted | 76.7 ± 17.3 | 54.2 ± 21.9 | 54.7 ± 17.3 | 70.2 ± 27.0 | p = ns | p = ns | p = ns |
| DLCO / VA | 102.5 ± 17.6 | 79.9 ± 30.3 | 83.5 ± 15.9 | 96.2 ± 32.4 | p = ns | p = ns | p = ns |
| HRCT | |||||||
| Normal (%) | 4.3% | 0% | 2.4% | 0% | |||
| Airways Disease Predominant (%) | 59.6% | 60.5% | 95.2% | 71.4% | |||
| ILD Predominant (%) | 34.0% | 10.5% | 0% | 3.6% | |||
| Emphysema Predominant (%) | 2.1% | 28.9% | 1 (2.4%) | 25.0%s | |||
| Emphysema Score | 19.9 ± 38.9 | 265 ± 342 | 39.6 ± 69.9 | 193.4 ± 313.9 | 0.001 | p = ns | 0.006 |
| ↓attenuation on the expiratory CT Score | 164.3 ± 169.7 | 278.9 ± 237.8 | 479.5 ± 232.7 | 422 ± 329.1 | 0.001 | 0.024 | p = ns |
| CAT Score | 23.6 ± 7.8 | 22.0 ± 6.5 | 25.2 ± 8.8 | p = ns | p = ns | p = ns | |
| SGRQ Score | 63.5 ± 18.5 | 60.2 ± 18.4 | 59.7 ± 16.3 | p = ns | p = ns | p = ns | |
| CRP (mg/L) | 2.3 ± 2.9 | 3.6 ± 4.6 | 5.2 ± 6.7 | 4.3 ± 3.9 | p = ns | p = ns | p = ns |
| Serum Insulin (μIU/mL) | 5.5 ± 3.2 | 3.7 ± 2.7 | 8.8 ± 4.7 | 5.3 ± 5.6 | 0.008 | p = ns | p = ns |
| Hemoglobin (mg/dL) | 12.8 ± 1.2 | 13.6 ± 2.3 | 11.9 ± 1.9 | 13.0 ± 2.0 | < 0.0001 | p = ns | p = ns |
| Red cell count (106 cells/μL) | 4.3 ± 0.5 | 4.6 ± 0.6 | 4.3 ± 0.4 | 4.6 ± 0.5 | 0.007 | p = ns | p = ns |
| Packed cell volume (%) | 39.6 ± 5.2 | 41.8 ± 6.4 | 36.7 ± 5.3 | 40.1 ± 5.8 | < 0.0001 | p = ns | 0.051 |
| Mean corpuscular volume (fL) | 92.4 ± 11.2 | 91.4 ± 10.8 | 84.7 ± 10.8 | 88.2 ± 9.8 | 0.004 | p = ns | p = ns |
| Blood eosinophils (%) | 4.6 ± 3.9 | 4.7 ± 4.7 | 5.3 ± 4.7 | 4.6 ± 4.43 | p = ns | p = ns | p = ns |
| Blood eosinophils (cells/μL) | 330.4 ± 319 | 343.5 ± 408 | 410.03 ± 403.73 | 337.5 ± 330.09 | p = ns | p = ns | p = ns |
| Sputum | |||||||
| Total cell count per ml | 1.38 (0.9 2.9) | 6.19 (3.2, 9.3) | 4.51 (2.5, 6.9) | 3.6 (2.4, 7.4) | p = ns | p = ns | p = ns |
| Macrophages per ml | 0.33 (0.2, 0.6) | 0.87 (0.4, 1.2) | 0.72 (0.4, 1.3) | 0.60 (0.3, 0.9) | p = ns | p = ns | p = ns |
| Neutrophils per ml | 0.87 (0.5, 2.8) | 5.22 (2.6, 8.3) | 2.63 (1.7, 5.9) | 2.60 (1.2, 6.7) | p = ns | p = ns | p = ns |
| Eosinophils per ml | 0.006 (0.0, 0.02) | 0.139 (0.04, 0.3) | 0.25 (0.04, 0.4) | 0.21 (0.1, 0.6) | p = ns | p = ns | p = ns |
| Lymphocytes per ml | 0.014 (0.0, 0.03) | 0.032 (0.02, 0.08) | 0.03 (0.01, 0.07) | 0.03 (0.01, 0.05) | p = ns | p = ns | p = ns |
aOut of the 34 occupational COPD, 25 were farmers, 4 were farmers + hard rock mining/sandblasting exposure and 5 had occupational dust exposures for at least 20 years
FEV1 Forced expiratory volume in 1 s, FVC Forced vital capacity, FEF25–75 Forced expiratory flow between 25 and 75% of FVC, PEF Peak expiratory flow, BD Bronchodilator, p-y Pack-years, h-y hour-years, sRaw specific airway resistance, sGaw specific airway conductance, TLC Total lung capacity, RV Residual volumeM, IOS Impulse oscillometry, R5 Resistance at 5 Hz, X5 Reactance at 5 Hz, AX Area under the reactance curve, Fres Resonant frequency, DLCO Diffusing lung co-efficient for carbon monoxide, KCO Transfer coefficient, SGRQ St. George’s Respiratory Questionnaire, CAT COPD assessment test, hsCRP high sensitivity C-reactive protein
Data are presented as means ± SD