A comparative analysis of errors in inhaler technique among COPD versus asthma patients

Figures & data

Table 1 Baseline characteristics of patients in COPD and asthma groups

Patient demographics	COPD (n=328)	Asthma (n=181)	P-value
Age (years), mean (SD, min-max)	64.6 (10.3, 29-89)	56.0 (14.5, 17-90)	<0.001a
Gender, n (%)
Female	114 (34.8)	140 (77.3)	<0.001b
Male	214 (65.2)	41 (22.7)
Duration (years), mean (SD, min-max)
Disease	9.5 (7.7, 0-40)	9.2 (9.5, 0-46)	0.727c
Inhaler therapy	8.0 (6.6, 0-35)	7.0 (7.6, 0-40)	0.146c
Inhaler type, n (%)
MDI	273 (83.2)	140 (77.3)	0.067b
Aerolizer^®/Handihaler^®	249 (75.9)	69 (38.1)	<0.001b
Diskus^®	78 (23.8)	75 (41.4)	<0.001b
Turbohaler^®	34 (10.4)	43 (23.8)	<0.001b
Nebulizer	111 (33.8)	32 (17.7)	<0.001b

Notes:

a Student’s t-test;

b Chi-square test;

c Mann–Whitney U test.

Abbreviation: MDI, metered dose inhaler.

Table 2 Errors in inhaler technique in COPD and asthma groups

	Patients with errors, n (%)		P-value
Instructions for MDI	COPD (n=223)	Asthma (n=124)
Take off the inhaler cap	18 (14.5)	18 (8.1)	0.046
Shake the MDI before use	114 (51.1)	71 (57.3)	0.162
Hold the MDI in a vertical position	22 (9.9)	24 (19.4)	0.01 1
Hold your head in a vertical position	22 (9.9)	25 (20.2)	0.007
Exhale before use	169 (75.8)	85 (68.5)	0.092
Put the mouthpiece in your mouth, and close your lips	39 (17.5)	23 (18.5)	0.456
Press the canister when inhaling slowly	36 (16.1)	24 (19.4)	0.269
Inhale deeply	96 (43.0)	48 (38.7)	0.251
Hold your breath for 10 seconds	58 (26.0)	36 (29.0)	0.314
Exhale and wait for 30-60 seconds before the other puff	32 (14.3)	14 (1 1.3)	0.263
Instructions for Aerolizer^®/Handihaler^®	COPD (n=205)	Asthma (n=78)
Pull off the Aerolizer cover	20 (9.8)	12 (15.4)	0.131
Open the mouthpiece of Aerolizer	20 (9.8)	11 (14.1)	0.200
Remove the capsule from the package and put it into the space	27(13.2)	14 (17.9)	0.201
Press the buttons on both sides of Aerolizer	55 (26.8)	41 (52.6)	0.0005
Hold your head in a vertical position	30 (14.6)	13 (16.7)	0.398
Turn your head away from Aerolizer and exhale	150 (73.2)	56 (71.8)	0.463
Put the mouthpiece in your mouth, and close your lips	26 (12.7)	12 (15.4)	0.338
Inhale deeply	93 (45.4)	42 (53.8)	0.382
Hold your breath for 10 seconds	40 (19.5)	26 (33.3)	0.012
Dispose of the capsule and put the cover back on the Aerolizer	20 (9.8)	9(11.5)	0.407
Instructions for Turbuhaler^®	COPD (n=32)	Asthma (n=39)
Remove the cover	2 (6.3)	8 (20.5)	0.082
Keep Turbuhaler upright	2 (6.3)	10 (25.6)	0.029
Twist grip at the base; twist around and then back until click is heard	5(15.6)	8 (20.5)	0.415
Hold your head in a vertical position	2 (6.3)	8 (20.5)	0.082
Exhale	17(53.1)	26 (66.7)	0.179
Put the mouthpiece in your mouth, and close your lips	4(12.5)	12 (30.8)	0.059
Breathe in strongly and deeply	16 (50.0)	20 (51.3)	0.552
Hold your breath for 10 seconds	10 (31.3)	11 (28.2)	0.491
Breathe out gently	3 (9.4)	7(17.9)	0.247
Put the cover back and wait for 30-60 seconds for the second dose	4(12.5)	7(17.9)	0.385
Instructions for Diskus^®	COPD (n=60)	Asthma (n=65)
Open Diskus by pushing the thumb grip right around until it clicks	15 (25.0)	18 (27.7)	0.446
Hold the mouthpiece toward you and push the lever away from you until it stops	6 (10.0)	8 (12.3)	0.452
Exhale	5 (8.3)	13 (20.0)	0.053
Hold your head in a vertical position	8 (13.3)	14 (21.5)	0.167
Put the mouthpiece to your lips	6 (10.0)	12 (18.5)	0.137
Breathe in strongly and deeply	45 (75.0)	52 (80.0)	0.324
Remove your Diskus	30 (50.0)	32 (49.2)	0.537
Hold your breath for 10 seconds	22 (36.7)	21 (32.3)	0.373
Breathe out gently	11 (18.3)	12 (18.5)	0.585
Close Diskus by sliding the thumb grip back to the original position and wait for 30-60 seconds for the second dose	10 (16.7)	4 (6.2)	0.057

Notes: Chi-square test. Values in bold indicate statistical significance (P<0.05).

Abbreviation: MDI, metered dose inhaler.

Table 3 Sub-analysis of errors in inhaler techniques that differed between COPD and asthma groups

	Age, mean (SD)	Gender, n (%)		Duration (years), mean (SD)
		Male	Female	Disease	Inhaler therapy
Instructions for MDI
Take off the inhaler cap
Incorrect use	57.9 (10.5)	17(10.0)	19 (10.7)	8.8 (8.8)	7.5 (6.6)
Correct use	62.4 (13.0)	153 (90.0)	158 (89.3)	9.8 (8.2)	8.1 (7.1)
P-value	0.058	0.481		0.494	0.643
Hold the MDI in a vertical position
Incorrect use	60.0 (12.9)	18 (10.6)	28 (15.8)	6.6 (4.7)	6.6 (4.8)
Correct use	62.3 (12.8)	152 (89.4)	149 (84.2)	10.0 (8.5)	8.1 (7.2)
P-value	0.275	0.100		<0.001	0.180
Hold your head in a vertical position
Incorrect use	58.3 (12.7)	21 (12.4)	26 (14.7)	6.6 (4.5)	5.8 (4.5)
Correct use	62.5 (12.8)	149 (87.6)	151 (85.3)	10.1 (8.6)	8.2 (7.2)
P-value	0.044	0.316		<0.001	0.006
Instructions for Aerolizer^®/Handihaler^®
Press the buttons on both sides of device
Incorrect use	63.2 (12.0)	41 (27.0)	55 (42.0)	10.0 (8.9)	8.3 (8.1)
Correct use	64.0 (10.5)	1 1 1 (73.0)	76 (58.0)	10.1 (8.5)	8.2 (7.0)
P-value	0.596	0.006		0.910	0.924
Hold your breath for 10 seconds
Incorrect use	62.6 (1 1.0)	40 (26.3)	26 (19.8)	10.7 (9.3)	8.9 (8.7)
Correct use	64.1 (1 1.0)	1 12 (73.7)	105 (80.2)	9.7 (8.3)	8.0 (7.0)
P-value	0.344	0.127		0.425	0.421
Instructions for Turbuhaler^®Keep inhaler upright
Incorrect use	61.9 (10.5)	4 (26.3)	8 (19.8)	5.0 (3.2)	4.3 (3.4)
Correct use	55.8 (14.3)	32 (88.9)	27 (77.1)	9.5 (8.9)	8.2 (7.4)
P-value	0.168	0.158		0.005	0.012

Notes: Chi-square test, Student’s t-test, Mann–Whitney U test. Values in bold indicate statistical significance (P<0.05).

Abbreviation: MDI, metered dose inhaler.