Table 3. Logistic Regression Analyses of the Walk On! Intervention on the Primary Composite Outcome of All-Cause Hospitalizations, Observation Stays, Emergency Department Visits, and Death.
| Health Care Use or Death | Participants, No. (%) | OR (95% CI) | ||
|---|---|---|---|---|
| Standard Care | Walk On! | Unadjusted | Adjusted | |
| Primary Intent-to-Treat Analysis: Follow-up for 12 mo After Randomizationa | ||||
| No. | 1349 | 1358 | NA | NA |
| All-cause acute care use and death | 864 (64.0) | 883 (65.0) | 1.04 (0.89-1.22) | 1.09 (0.92-1.28) |
| Hospitalizations | 499 (37.0) | 502 (36.9) | 1.00 (0.85-1.17) | 1.05 (0.89-1.24) |
| Observation stays | 269 (19.9) | 295 (21.7) | 1.11 (0.93-1.34) | 1.13 (0.93-1.37) |
| Emergency department visits | 694 (51.4) | 702 (51.7) | 1.01 (0.87-1.17) | 1.03 (0.88-1.20) |
| Death | 117 (8.7) | 117 (8.6) | 0.99 (0.76-1.30) | 1.02 (0.77-1.36) |
| COPD-related acute care useb | 398 (29.5) | 411 (30.3) | 1.04 (0.88-1.22) | 1.10 (0.93-1.31) |
| Prespecified, As-Treated, IPTW Analysis: Follow-up for 2-12 mo After Randomizationc | ||||
| No. | 1310d | 321 | NA | NA |
| All-cause acute care use and death | 781 (59.6) | 185 (57.6) | 0.92 (0.72-1.18) | 1.05 (0.82-1.35) |
| Hospitalizations | 433 (33.1) | 91 (28.3) | 0.80 (0.61-1.05) | 0.84 (0.65-1.10) |
| Observation stays | 230 (17.6) | 53 (16.5) | 0.93 (0.67-1.29) | 0.92 (0.66-1.28) |
| Emergency department visits | 610 (46.6) | 144 (44.9) | 0.93 (0.72-1.19) | 1.07 (0.84-1.36) |
| Death | 95 (7.3) | 13 (4.0) | 0.54 (0.30-0.98) | 0.62 (0.35-1.11) |
| COPD-related acute care useb | 195 (14.9) | 48 (15.0) | 1.01 (0.71-1.42) | 0.96 (0.68-1.35) |
Abbreviations: COPD, chronic obstructive pulmonary disease; IPTW, inverse probability of treatment weighting; NA, not applicable; OR, odds ratio.
Intent to treat: adjusted ORs are from logistic regression models that included age, forced expiratory volume in the first second of expiration predicted, Charlson Comorbidity Index, oxygen use, hospitalization for COPD in the previous 12 months, outpatient-treated COPD exacerbation in the previous 12 months, length of time since acute care use to randomization, use of long-acting β-2 agonist or inhaled corticosteroids, physical activity level, and study site.
The COPD-related acute care use includes hospitalizations, observation stays, and emergency department visits for COPD exacerbations.
As treated: adjusted ORs are from logistic regression models that included stabilized propensity score IPTW to balance baseline characteristics (sociodemographics, health behaviors, disease severity, comorbidities, inhalers/medications, and health care use in the prior year) between patients who participated in Walk On! and the standard care group.
Standard care patients not included in the as-treated analysis were due to disenrollment (n = 17) and deaths (n = 22) in the first 2 months after randomization.