Table 2.
Impact of Global Initiative for Chronic Obstructive Lung Disease 2011 classification, 6-minute-walk distance, and accelerometry on risk of chronic obstructive pulmonary disease–related hospitalization or all-cause mortality
| Risk Factor | Model 1: GOLD 2011 |
Model 2: GOLD + 6-Min-Walk |
Model 3: GOLD + Accelerometry |
|||
|---|---|---|---|---|---|---|
| HR (95% CI) | P Value | HR (95% CI) | P Value | HR (95% CI) | P Value | |
| GOLD group D vs. A | 7.34 (1.00, 53.61) | 0.050 | 3.73 (0.49, 28.39) | 0.203 | 3.85 (0.51, 29.04) | 0.191 |
| GOLD group C vs. A | 2.316 (0.20, 24.01) | 0.530 | 2.05 (0.19, 22.82) | 0.558 | 1.75 (0.16, 19.62) | 0.649 |
| GOLD group B vs. A | 3.26 (0.42, 25.07) | 0.257 | 2.16 (0.28, 16.90) | 0.464 | 2.14 (0.28, 16.75) | 0.467 |
| Prior exacerbations | 1.39 (1.10, 1.75) | 0.005 | 1.34 (1.07, 1.69) | 0.011 | 1.44 (1.14, 1.81) | 0.002 |
| Age, per 10 yr | 1.69 (1.19, 2.39) | 0.004 | 1.38 (0.96, 2.00) | 0.086 | 1.46 (1.01, 2.10) | 0.043 |
| Charlson comorbidity index | 0.94 (0.83, 1.07) | 0.343 | 0.92 (0.81, 1.05) | 0.226 | 0.93 (0.82, 1.06) | 0.254 |
| CST vs. health education | 1.24 (0.77, 2.00) | 0.386 | 1.23 (0.75, 1.99) | 0.413 | 1.24 (0.76, 2.01) | 0.392 |
| Duke vs. Ohio State site | 1.03 (0.56, 1.90) | 0.928 | 1.07 (0.57, 2.00) | 0.831 | 1.00 (0.54, 1.86) | 0.997 |
| 6MWD, per 150 m | — | — | 0.50 (0.34, 0.73) | 0.0003 | — | — |
| Total steps, per 1,000 | — | — | — | — | 0.80 (0.70, 0.92) | 0.002 |
Definition of abbreviations: 6MWD = 6-minute-walk distance; CI = confidence interval; COPD = chronic obstructive pulmonary disease; CST = coping skills training; GOLD = Global Initiative for Chronic Obstructive Lung Disease; HR = hazard ratio.