Table 1.
Characteristics of the COPD cohort.
| All COPD N = 637 | Comparison based on prior AHRF in COPD | |||
|---|---|---|---|---|
| No AHRF N = 323 | AHRF N = 314 | p | ||
| Age (years) | 74 (66–80) | 75 (68–82) | 65 (73–78) | <0.01 |
| Sex (male) | 278 (43.6) | 148 (45.8) | 140 (44.59) | 0.75 |
| Pack years | 40 (33–56) | 40 (32–55) | 40 (33–56) | 0.59 |
| Current smokers | 126 (19.8) | 49 (15.2) | 77 (24.5) | 0.02 |
| Hypercapnia | 233 (36.6) | 73 (22.6) | 145 (46.18) | <0.01 |
| BMI | 25.5 (213–32.5) | 24.6 (21.3–32.0) | 26·7 (21.4–33.6) | 0.28 |
| FEV1 | 0.9 (0.65–1.26) | 0.98 (0.72–1.43) | 0·82 (0.59–1.12) | <0.01 |
| FEV1pp | 41 (41–55) | 47 (34–60) | 36 (28–49) | <0.01 |
| FVCpp | 73 (57–90) | 78 (63–94) | 69 (51–85) | <0.01 |
| DLCOpp | 48.9 (38.9–73.3) | 60.9 (55.1–66.7) | 43.6 (36.2–64.9) | <0.01 |
| RVpp | 104.35 (89.5–123.4) | 100 (88.03–108.93) | 112 (93.4–134.25) | 0.09 |
| PaO2 | 7.9 (7.1–8.7) | 7.9 (7.2–8.7) | 7.8 (7.0–8.6) | 0.08 |
| PaCO2 | 5.9 (4.9–6.9) | 5.5 (4.7–6.4) | 6.4 (5.4–7.5) | <0.01 |
| HCO3 | 28.4 (26.2–31.5) | 27.5 (25.6–30.1) | 29 (26.7–32.8) | <0.01 |
| BE | 3.7 (1.5–6.5) | 3.4 (1.2–5.7) | 4.3 (2.3–7.2) | <0.01 |
| On LTOT | 304 (47.7) | 146 (45.2) | 158 (50.3) | 0.2 |
| Emphysema | 284 (44.6) | 177 (54.8) | 142 (45.2) | 0.04 |
| Upper lobe emphysema | 113 (39.8) | 58 (51.3) | 55 (48.7) | 0.21 |
| Lower lobe emphysema | 14 (4.9) | 12 (85.7) | 2 (14.3) | 0.12 |
| No zonal predominance | 157 (55.3) | 89 (56.69) | 68 (43.3) | 0.79 |
| LZVI-UZVI | — | — | — | — |
| Bronchiectasis | 101 (15.9) | 50 (15.5) | 51 (16.2) | 0·79 |
| Change in FEV1/ml/year | −54 (−160-23.5) | −65.5 (−172.8-8) | −49 (−143.5−32.5) | 0·33 |
| Follow-up (years) | 1.33 (0.31–2.65) | 1.30 (0.31–2.56) | 0.31 (1.34–2.87) | 0·62 |
| Death | 415 (65.1) | 192 (59.4) | 223 (71.02) | <0.01 |
Data are shown as mean (SE) or median (IQR) for quantitative measures, and n (%) for binary outcomes, which are further denoted by italic text.