Bronchodilator reversibility in patients with COPD revisited: short-term reproducibility

Figures & data

Table 1 Mean changes and mean difference between absolute change in FEV₁ on Day 1 and Day 10

	Day 1	Day 10
Albuterol, n	55	53
Mean (n) change in FEV1 (SD) (mL)	261 (199)	237 (158)
Mean (n) difference between Day 1 and Day 10 (SD) (mL)*		47 (112)
Ipratropium, n	55	54
Mean (n) change in FEV1 (SD) (mL)	253 (180)	241 (163)
Mean (n) difference between Day 1 and Day 10 (SD) (mL)*		27 (170)

Note:

* The mean difference was calculated using the number of patients with data available on Day 10.

Abbreviations: FEV₁, forced expiratory volume in 1 second; SD, standard deviation.

Table 2 Difference in FEV₁ response to albuterol and ipratropium between Day 1 and Day 10, stratified by specific thresholds

Difference between Day 1 and Day 10 (mL)	Albuterol, n=53*	Ipratropium, n=54*
<100	31	28
≥100 to <150	12	8
≥150 to <200	4	9
≥200	6	9

Notes:

* One patient completed the ipratropium study period but not the albuterol study period; therefore, n=53 for albuterol and n=54 for ipratropium.

Abbreviation: FEV₁, forced expiratory volume in 1 second.

Figure 1 Response to albuterol on Day 1 compared with Day 10.

Abbreviation: FEV₁, forced expiratory volume in 1 second.

Figure 2 Change in FEV₁ on Day 1 for albuterol and ipratropium.

Notes: Symbols demonstrate “reversibility” status on Day 10. Reversibility was defined as an increase in FEV₁ of ≥12% and ≥200 mL following administration of albuterol or ipratropium. The square symbols represent patients whose reversibility status changed between Day 1 and Day 10.
Abbreviation: FEV₁, forced expiratory volume in 1 second.

Figure S1 Schematic diagram of the study design.

Notes: *Drugs administered immediately after spirometry. S1: pre-dose spirometry; S2: spirometry 1 hour after drug 1; S3: spirometry 1 hour after drug 2.