Table 4.
Univariate and Multivariate Associations with 1-Year Mortality
| Variable | Univariate Analysis | Multivariate Analysis | ||
|---|---|---|---|---|
| HR (95% CI) | P-Value | HR (95% CI) | P-Value | |
| Age (per increase of 10-year) | 1.77 (1.29–2.44) | <0.001 | 1.58 (1.05–2.38) | 0.027 |
| Sex (female vs male) | 0.84 (0.49–1.42) | 0.504 | ||
| Body-mass index | 0.98 (0.93–1.04) | 0.541 | ||
| Smoking status | ||||
| Current smoker vs Never smoked | 0.83 (0.39–1.79) | 0.640 | ||
| Former smoker vs never smoked | 0.92 (0.51–1.68) | 0.791 | ||
| COPD stage (per increase to next stage) | 1.28 (0.95–1.71) | 0.106 | 1.43 (0.97–2.10) | 0.068 |
| Congestive heart failure (yes vs no) | 2.00 (1.20–3.33) | 0.008 | 1.37 (0.77–2.44) | 0.289 |
| Renal dysfunction (yes vs no) | 1.16 (0.66–2.03) | 0.611 | ||
| Exacerbations during preceding year (yes vs no) | 1.88 (1.11–3.17) | 0.018 | 1.63 (0.92–2.88) | 0.093 |
| NT-proBNP (≥551.35 vs.<551.35 ng/L) | 6.14 (3.46–10.90) | <0.001 | 4.47 (2.38–8.41) | <0.001 |
| Neutrophil count (per increase of 1×109/L) | 1.03 (0.97–1.08) | 0.347 | ||
| Hemoglobin (per increase of 1 standard deviation g/L) | 0.71 (0.55–0.90) | 0.006 | 1.03 (0.78–1.36) | 0.844 |
| D-dimer (per increase of 1 standard deviation ng/mL) | 1.39 (1.20–1.60) | <0.001 | 1.26 (1.02–1.55) | 0.033 |
| Creatinine (per increase of 1 standard deviation μmmol/L) | 1.12 (0.91–1.38) | 0.294 | ||
| BUN (per increase of 1 standard deviation mmol/L) | 1.34 (1.18–1.51) | <0.001 | 1.20 (1.00–1.43) | 0.052 |
| pH | ||||
| pH<7.35 vs 7.35≤ pH ≤7.45 | 2.14 (1.18–3.86) | 0.012 | 1.24 (0.60–2.54) | 0.558 |
| pH>7.45 vs 7.35≤ pH ≤7.45 | 0.71 (0.22–2.28) | 0.562 | ||
| PaO2(<60 vs.≥60 mmHg) | 1.95 (0.96–3.96) | 0.066 | 0.75 (0.30–1.86) | 0.537 |
| PaCO2(≥50 vs.<50 mmHg) | 1.90 (1.11–3.23) | 0.019 | 1.41 (0.70–2.87) | 0.338 |
Abbreviations: HR, Hazard ratio; 95% CI, 95% confidence interval; COPD, Chronic obstructive pulmonary disease; BUN, blood urea nitrogen; PaO2, partial pressure of O2; PaCO2, partial pressure of CO2.