Differences in Adherence to Common Inhaled Medications in COPD

Figures & data

Table 1.  Baseline characteristics

	N = 795 Overall	Good ≥75–≤125%	Sub-optimal ≥50–<75%	Underuse <50%	Overuse >125%	P
Age in years (Mean (SD))	67.8 (9.9)	66.5 (9.6)	66.5 (10.3)	64.3 (11.0)	67.2 (9.7)	0.100
Sex (Number of men (%))	486 (61.1)	560 (61.6)	112 (53.6)	62 (53.9)	87 (59.6)	0.102
Smoking status (Number (%))
Current smoker	212 (26.7)	246 (27.1)	49 (23.4)	45 (39.1)	56 (38.4)	0.001
Ex-smoker	583 (73.3)	663 (72.9)	160 (76.6)	70 (60.9)	90 (61.6)
Lung function (Mean (SD))
FEV­1 in Litres	1.4 (0.6)	1.4 (0.6)	1.4 (0.5)	1.5 (0.6)	1.3 (0.5)	0.001
FEV1% predicted	52.1 (19.4)	51.0 (17.8)	52.4 (18.4)	55.3 (20.1)	47.3 (16.9)	0.004
FEV1/VC ratio	44.5 (13.6)	42.3 (12.6)	45.5 (13.3)	48.0 (15.2)	42.3 (12.7)	0.000

Table 2.  Number (%) of patients in the subgroups of therapy adherence per medication

Medication	Good ≥75–≤125%	Suboptimal ≥50–<75%	Underuse <50%	Overuse >125%	Months used median (IQR)
Tiotropium (n = 566)	429 (75.8)	68 (12.0)	36 (6.4)	33 (5.8)	28.7 (15.1–35.5)
Ciclesonide (n = 22)	15 (68.2)	3 (13.6)	0	4 (18.2)	23.5 (15.8–35.5)
Salmeterol (n = 39)	26 (66.7)	6 (15.4)	5 (12.8)	2 (5.1)	27.1 (6.9–35.2)
Fluticasone (n = 73)	46 (63.0)	17 (23.3)	4 (5.5)	6 (8.2)	25.7 (12.5–34.9)
Formoterol/Budesonide (n = 91)	56 (61.5)	12 (13.2)	4 (4.4)	19 (20.9)	31.2 (15.9–36.5)
Salmeterol/Fluticasone (n = 500)	295 (59.0)	95 (19.0)	55 (11.0)	55 (11.0)	27.5 (13.7–35.0)
Budesonide (n = 44)	23 (52.3)	1 (2.3)	3 (6.8)	17 (38.6)	28.2 (17.4–36.7)
Beclomethasone (n = 44)	19 (43.2)	7 (15.9)	8 (18.2)	10 (22.7)	15.7 (7.5–31.7)

Table 3.  Nominal regression analyses of medication vs. therapy adherence

		OR	95% CI
Suboptimal (≥50–<75%) (n = 209)	FEV1 (L) baseline	1.1	0.8–1.4
	Ciclesonide	1.3	0.4–4.4
	Salmeterol	1.4	0.6–3.6
	Fluticasone	2.3	1.3–4.3
	Formoterol/Budesonide	1.4	0.7–2.7
	Salmeterol/Fluticasone	2.0	1.4–2.9
	Budesonide	0.3	0.04–2.1
	Beclomethasone	2.3	0.9–5.7
Underuse (<50%) n = 115)	FEV1 (L) baseline	1.5	1.1–2.1
	Ciclesonide	**	**
	Salmeterol	2.1	0.8–5.9
	Fluticasone	1.1	0.4–3.2
	Formoterol/Budesonide	0.8	0.3–2.4
	Salmeterol/Fluticasone	2.3	1.5–3.6
	Budesonide	1.6	0.4–5.5
	Beclomethasone	4.6	1.9–11.3
Overuse (>125%) (n = 145)***	FEV1 (L) baseline	0.6	0.4–0.8
	Ciclesonide	3.6	1.1–11.6
	Salmeterol	0.5	0.1–4.1
	Fluticasone	1.6	0.6–4.0
	Formoterol/Budesonide	4.9	2.6–9.3
	Salmeterol/Fluticasone	2.3	1.5–3.7
	Budesonide	9.8	4.7–20.2
	Beclomethasone	7.7	3.3–18.1

*Good adherence and tiotropium were set as reference. All corrected for FEV1 in Litres (L) at baseline.

**Not possible to calculate.

***One missing due to missing lung function data.