Comparison of peak inspiratory flow rate via the Breezhaler®, Ellipta® and HandiHaler® dry powder inhalers in patients with moderate to very severe COPD: a randomized cross-over trial

Table 4 Comparison of mean PIF and pressure drop values based on age

Age (years)	Variable	Breezhaler®	Ellipta®	HandiHaler®
Age (years)	R (cmH₂O^0.5[L/min]^− 1)^a	0.060	0.090	0.163
40–64	n	27	27	27
	PIF (L/min)	123 ± 20	88 ± 13	53 ± 9
	Range (Min-Max)	77–156	57–109	32–70
	Pressure drop at PIF (cmH₂O)	56 ± 17	64 ± 18	76 ± 23
	ΔPIF vs Breezhaler® (L/min); 95% CI	–	35; 30 to 40	70; 65 to 76
	P-value	–	< 0.0001	< 0.0001
65–74	n	46	42	46
	PIF (L/min)	101 ± 22	73 ± 13	47 ± 9
	Range (Min-Max)	54–152	48–99	22–68
	Pressure drop at PIF (cmH₂O)	38 ± 16	45 ± 16	61 ± 23
	ΔPIF vs Breezhaler® (L/min); 95% CI	–	28; 23 to 30	54; 49 to 58
	P-value	–	< 0.0001	< 0.0001
≥75	n	24	22	24
	PIF (L/min)	105 ± 21	75 ± 16	50 ± 9
	Range (Min-Max)	65–151	45–102	29–66
	Pressure drop at PIF (cmH₂O)	41 ± 17	48 ± 18	67 ± 22
	ΔPIF vs Breezhaler® (L/min); 95% CI	–	30; 24 to 35	55; 49 to 62
	P-value	–	< 0.0001	< 0.0001

Data are presented as mean ± standard deviation unless stated otherwise. P-values for subgroup analysis are exploratory in nature
CI confidence interval, n number of patients, ΔPIF difference in mean PIF values, PIF peak inspiratory flow rate, R intrinsic airflow resistance of the inhaler
Poor quality (flat-line) inhalational profiles with erroneous PIF values were not considered in the analysis
^aData published previously [19, 20]

ISSN: 1471-2466