Table 2.
Summary of dyspnea measures, health status, and pulmonary function test in participants with oPIF and sPIF against the medium-low resistance DPIs.
| oPIF∗ | sPIF∗ | P value | |
|---|---|---|---|
| mMRC score, mean (95% CI [n]) | 1.6 (1.4–1.7 [250]) | 2.1 (2.0–2.2 [273]) | <0.001 |
| BDI, mean (95% CI [n]) | 6.1 (5.8–6.3 [234]) | 5.1 (4.9–5.4 [272]) | <0.001 |
| Total CAT score, mean (95% CI [n]) | 19.5 (18.6–20.4 [250]) | 21.5 (19.7–23.3 [68]) | 0.05 |
| SGRQ score, mean (95% CI [n]) | 50.0 (47.9–52.1 [250]) | 52.8 (48.8–56.8 [68]) | 0.22 |
| Post-IPR percent predicted FEV1, mean (95% CI [n]) | 54.7 (52.9–56.5 [252]) | 39.8 (37.9–41.8 [273]) | <0.001 |
| Post-IPR percent predicted FVC, mean (95% CI [n]) | 75.9 (74.1–77.7 [252]) | 66.2 (64.4–68.0 [273]) | <0.001 |
∗ oPIF was defined as PIF >60 L/min and sPIF as PIF ≤60 L/min. BDI = baseline dyspnea index; CAT = COPD Assessment Test; CI = confidence interval; DPI = dry powder inhaler; FEV1 = forced expiratory volume in 1 second; FVC = forced vital capacity; IPR = ipratropium; mMRC = modified Medical Research Council; oPIF = optimal PIF; PIF = peak inspiratory flow; SGRQ = St. George's Respiratory Questionnaire; sPIF = suboptimal PIF.