Table 1.
Characteristics of the study sample controls versus COPD subjects.
| Characteristics | Control | COPD | P-value |
|---|---|---|---|
| Subjects, n | 47 | 66 | |
| Sex, % males | 32 | 45 | ns |
| Mean age, yrs, mean (SD) | 70 (10) | 70 (9) | ns |
| Never-smoker; %/n | 58/27 | 8/5 | <0.001 |
| BMI (kg/m2); mean (SD) | 25.9 (3.4) | 26.3 (7.1) | ns |
| CCI 0–3 (%/n) | 100/47 | 83/55 | <0.05 |
| CCI ≥ 4 (%/n) | 0 | 17/11 | <0.05 |
| FEV1% predicted; mean (SD) | 105 (16) | 41 (16) | <0.001 |
| SAT, % (air); mean (SD) | 98 (2) | 91.6 (6.0) | <0.001 |
| LTOT; %/n | 0/0 | 42/28 | |
| Portion size, vegetables; mean (SD) | 2.1 (0.6) | 1.8 (0.6) | <0.05 |
| MDS; mean (SD) | 21.9 (3.9) | 18.7 (3.7) | <0.0001 |
| PC; mean (SD) (nmol/mg protein) | 0.326 (0.018) | 0.321 (0.006) | ns |
| General | |||
| Hemoglobin; mean (SD) (ref: 134–170 g/L) | na | 143 (13) | |
| Creatinine; mean (SD) (ref: 49–90 µmol/L) | na | 78 (25) | |
| Albumin; mean (SD) (ref: 36–45 g/L) | na | 38.1 (3.3) | |
| Urea; mean (SD) (ref: 3.5–8.2 mmol/L) | na | 7.3 (3.1) | |
| Inflammation | |||
| WBC; mean (SD) (ref: 3.5–8.8 × 10*9/L) | na | 9.0 (2.6) | |
| Hs-CRP; mean (SD) (ref: <3 mg/L) | na | 7.3 (13.3) | |
| Fibrinogen; mean (SD) (ref: 2–4 g/dL) | na | 3.7 (1.0) | |
| IL-6; mean (SD) (ref: <7 ng/L) | na | 6.9 (12.8) | |
| Fe | |||
| sTfRs; mean (SD) (ref: 1.2–2.9 mg/L) | na | 3.00 (1.14) | |
| Fe; mean (SD) (ref: 9–34 µmol/L) | na | 14.37 (6.30) | |
| Transferrin; mean (SD) (ref: 1.9–3.3 g/L) | na | 2.43 (0.40) | |
| Ferritin; mean (SD) (ref: 34–275 µg/L) | na | 161.0 (153.3) | |
| Carotenoids, mean (SD) (µmol/L) | |||
| Lutein; | 0.48 (0.21) | 0.36 (0.25) | ns |
| β-cryptoxanthin | 0.10 (0.06) | 0.07 (0.08) | <0.05 |
| Lycopene | 0.48 (0.21) | 0.41 (0.20) | ns |
| α-carotene | 0.23 (0.18) | 0.09 (0.06) | <0.001 |
| β-carotene | 0.68 (0.39) | 0.38 (0.21) | <0.001 |
| Total carotenoids | 1.96 (1.00) | 1.31 (0.53) | <0.001 |
Results are presented as means (±1 S.D.) for continuous variables and percentage for categorical variables. P-values are from chi-square test (nominal data), Student’s t-test (normally distributed data), or Mann–Whitney U-test (not normally distributed data). na: not analyzed; ns: not significant (p-value ≥ 0.05).
BMI: body mass index; CCI: Charlson Comorbidity Index; Fe: iron; FEV1: forced expiratory volume in one second % predicted (according to Hedenström); hs-CRP: high-sensitivity C-reactive protein; IL-6: interleukin 6; MDS: Mediterranean Diet Score; PC: protein carbonylation; SAT: blood oxygenation saturation measured at air breathing; sTfRs: soluble transferrin receptors; WBC: white blood cell count; yrs, years.