Inspiratory Flow Parameters Through Dry Powder Inhalers in Healthy Volunteers and Patients with Chronic Obstructive Pulmonary Disease (COPD): Device Resistance Does Not Limit Use in COPD

Figures & data

Table 1 Patient Baseline Characteristics

	Total N=200
	COPD n=100	Healthy Volunteers n=100
Mean (SD) Age, years	70 (7)	31 (11)
Sex, n (%)
Female	21 (21)	60 (60)
Male	79 (79)	40 (40)
Mean (SD) Weight, kg	83.2 (17.0)	73.2 (14.6)
Mean (SD) Height, cm	171.0 (7.7)	171.8 (8.9)
Mean (SD) BMI	28.4 (5.5)	24.8 (4.6)
Nicotine user, n (%)
Ex-user	53 (53)	15 (15)
Never used	4 (4)	74 (74)
User	43 (43)	11 (11)
Mean FEV1, L (min–max)	1.58 (0.51–3.77)	3.70 (2.41–5.95)
Mean FEV1, % predicted (min–max)	55 (16–96)	97 (81–122)
Mean FEV1/FVC (min–max)	0.50 (0.20–0.74)	81.7 (69.0–96.0)
Mean FVC (min–max)	3.1 (1.2–5.9) L	4.6 (3.1–7.1)

Abbreviations: BMI, body mass index; FEV₁, forced expiratory volume in one second; SD, standard deviation.

Table 2 Disease Characteristics for Patients with COPD

	Subjects with COPD (N=100) n (%)
mMRC dyspnoea score
Grade 0	11 (11)
Grade 1	43 (43)
Grade 2	31 (31)
Grade 3	15 (15)
Grade 4	0
CAT score
Very low impact (0–9)	18 (18)
Medium impact (10–20)	53 (53)
High impact (21–30)	26 (26)
Very high impact (>31)	3 (3)
ABCD classification
Group A	20 (20)
Group B	58 (58)
Group C	8 (8)
Group D	14 (14)

Abbreviations: CAT, COPD assessment test; COPD, chronic obstructive pulmonary disease; mMRC, modified Medical Research Council.

Figure 1 PIF rate for healthy volunteers and patients with COPD with each inhaler.

Note: Data presented for individual patients with mean value.

Abbreviatios: COPD, chronic obstructive pulmonary disease; PIF, peak inspiratory flow.

Table 3 Mean PIF, Mean Inspiratory Volume, Time to PIF and Duration of Inhalation for Healthy Volunteers and Patients with COPD

Inhaler	Mean PIF (Min-Max) L/Min		Mean Inspiratory Volume (Min–Max) L		Time to PIF s		Duration of Inhalation s
	HV	COPD	HV	COPD	HV	COPD	HV	COPD
Center slot Easyhaler	72.2 (32.4–102.3)	68.2 (48.8–89.9)	2.3 (0.7–6.3)	2.2 (0.9–5.1)	0.6 (0.2–1.7)	0.5 (0.2–1.0)	3.0 (0.8–7.4)	3.2 (1.3–7.7)
Standard Easyhaler	62.0 (33.5–88.5)	58.4 (35.7–77.3)	2.1 (0.6–5.7)	2.0 (0.8–3.6)	0.6 (0.2–2.8)	0.5 (0.2–1.3)	3.2 (0.9–7.3)	3.4 (1.6–7.6)
HandiHaler	47.2 (27.5–69.5)	49.5 (29.9–73.1)	3.2* (0.9–5.6)	2.5* (0.8–4.8)	1.7 (0.8–6.9)	0.9 (0.2–4.2)	5.6 (2.4–9.8)	4.7 (1.4–9.7)

Note: *Statistically significant difference with p<0.01.

Figure 2 Inspiratory volume for healthy volunteers and patients with COPD with each inhaler.

Notes: Data presented for individual patients with mean.

Abbreviation: COPD, chronic obstructive pulmonary disease.

Table 4 Mean PIF Measured Using In-Check Dial versus Spirometry

Inhaler	Mean PIF (Spirometer, Main Study), L/Min	Mean PIF (In-Check Dial), L/Min	Correlation with In-Check Dial	p-value
Center slot Easyhaler	68.2	64.8	0.74	<0.0001
Standard Easyhaler	58.3	50.1	0.68	<0.0001
HandiHaler	49.5	40.7	0.68	<0.0001

Figure 3 Preference and acceptability of different inhaler characteristics for the Easyhaler and HandiHaler inhalers among patients with COPD. Patients were asked about preference and inhaler characteristics with the following questions and statements: which inhaler would you choose?; instruction leaflet of the inhaler is easier to understand; the inhaler is easier to learn how to use; taking the drug from the inhaler is easier; inhalation through the inhaler is easier; the inhaler has a more pleasant size; the design of the inhaler is more pleasant; the inhaler is handier to carry; mouthpiece of the inhaler is better.

Abbreviation: COPD, chronic obstructive pulmonary disease.