Real-world health care utilization in asthma patients using albuterol sulfate inhalation aerosol (ProAir^® HFA) with and without integrated dose counters

Figures & data

Figure 1 Patient selection.

Notes: *The date of first prescription for albuterol inhalation aerosol with IDC (albuterol with IDC cohort) and without IDC (albuterol without IDC cohort) was set as the index date.
Abbreviations: COPD, chronic obstructive pulmonary disease; EIB, exercise-induced bronchoconstriction; HFA, hydrofluoroalkane; IDC, integrated dose counter; NDC, National Drug Code; SABA, short-acting beta agonist.

Table 1 Patient demographic and clinical characteristics, by age group

Parameter	Albuterol inhalation aerosol with IDC				Albuterol inhalation aerosol without IDC
	Age ≤17 years (N=39,826)	Age 18–39 years (N=39,358)	Age 40+ years (N=56,121)	Total (N=135,305)	Age ≤17 years (N=86,149)	Age 18–39 years (N=85,530)	Age 40+ years (N=115,564)	Total (N=287,243)
Mean (SD) age, years	11.0 (3.8)	28.5 (6.8)	51.6 (6.9)	32.9 (18.1)	11.0 (3.8)a	28.6 (6.7)b	51.5 (7.0)c	32.5 (18.0)d
Gender, n (%)
Male	22,686 (57.0)	15,808 (40.2)	19,279 (34.4)	57,773 (42.7)	48,674 (56.5)	33,521 (39.2)b	38,630 (33.4)c	120,825 (42.1)d
Female	17,140 (43.0)	23,550 (59.8)	36,842 (65.6)	77,532 (57.3)	37,475 (43.5)	52,009 (60.8)b	76,934 (66.6)c	166,418 (57.9)d
Comorbid conditions, n (%)
Rhinitis	8,417 (21.1)	5,953 (15.1)	9,784 (17.4)	24,154 (17.9)	15,045 (17.5)a	11,893 (13.9)b	18,533 (16.0)c	45,471 (15.8)d
GERD	558 (1.4)	1,365 (3.5)	4,037 (7.2)	5,960 (4.4)	1,018 (1.2)a	2,693 (3.1)b	7,676 (6.6)c	11,387 (4.0)d
Eczema	2,206 (5.5)	1,533 (3.9)	2,544 (4.5)	6,283 (4.6)	4,229 (4.9)a	3,042 (3.6)b	4,780 (4.1)c	12,051 (4.2)d
Ischemic heart disease	5 (0.02)	42 (0.1)	1,079 (1.9)	1,126 (0.8)	5 (0.01)	93 (0.1)	2,234 (1.9)	2,332 (0.8)
Other chronic respiratory diseases	85 (0.2)	69 (0.2)	244 (0.4)	398 (0.3)	122 (0.1)a	173 (0.2)	563 (0.5)	858 (0.3)
Baseline medications, n (%)
Corticosteroids (oral/injectable)	5,187 (13.0)	7,206 (18.3)	15,338 (27.3)	27,731 (20.5)	9,538 (11.1)a	13,441 (15.7)b	27,367 (23.7)c	50,346 (17.5)d
Asthma drug therapy
None	25,131 (63.1)	26,457 (67.2)	29,281 (52.2)	80,869 (59.8)	60,797 (70.6)a	62,867 (73.5)b	67,418 (58.3)c	191,082 (66.5)d
Other respiratory medications (SAMA, LTRA, other respiratory medications)	6,590 (16.5)	4,661 (11.8)	10,555 (18.8)	21,806 (16.1)	11,100 (12.9)a	7,008 (8.2)b	17,115 (14.8)c	35,223 (12.3)d
LABAe	2,514 (6.3)	5,161 (13.1)	12,184 (21.7)	19,859 (14.7)	4,551 (5.3)a	9,327 (10.9)b	22,015 (19.1)c	35,893 (12.5)d
ICSe	11,679 (29.3)	10,800 (27.4)	22,793 (40.6)	45,272 (33.5)	19,952 (23.2)a	19,535 (22.8)b	41,605 (36.0)c	81,092 (28.2)d
LAMA	6 (0.02)	49 (0.1)	480 (0.9)	535 (0.4)	9 (0.01)	90 (0.1)	812 (0.7)c	911 (0.3)d
Baseline all-cause hospitalizations and ED visits
Patients with hospitalizations, n (%)	588 (1.5)	1,519 (3.9)	2,102 (3.7)	4,209 (3.1)	1,344 (1.6)	3,284 (3.8)	4,806 (4.2)c	9,434 (3.3)d
Number of hospitalizations, mean (SD)	0.017 (0.2)	0.046 (0.3)	0.044 (0.2)	0.037 (0.2)	0.018 (0.2)	0.045 (0.3)	0.049 (0.3)c	0.039 (0.2)d
Patients with ED visits, n (%)	5,629 (14.1)	6,754 (17.2)	7,482 (13.3)	19,865 (14.7)	12,995 (15.1)a	15,287 (17.9)b	15,866 (13.7)c	44,148 (15.4)d
Number of ED visits, mean (SD)	0.182 (0.5)	0.260 (0.7)	0.182 (0.6)	0.204 (0.6)	0.195 (0.5)a	0.266 (0.8)	0.188 (0.6)	0.213 (0.6)d

Notes:

a p<0.05 versus patients aged ≤17 in the albuterol with IDC cohort;

b p<0.05 versus patients aged 18–39 in the albuterol with IDC cohort;

c p<0.05 versus patients aged 40+ in the albuterol with IDC cohort;

d p<0.05 versus total patients in the albuterol with IDC cohort;

e not mutually exclusive groups; includes combination LABA/ICS products.

Abbreviations: ED, emergency department; GERD, gastroesophageal reflux disease; ICS, inhaled corticosteroids; IDC, integrated dose counter; LABA, long-acting beta agonist; LAMA, long-acting muscarinic antagonist; LTRA, leukotriene receptor antagonist; SAMA, short-acting muscarinic antagonist; SD, standard deviation.

Table 2 Health care utilization among users of albuterol inhalation aerosol with and without IDC, by age group during 6 months of follow-up

Parameter	Albuterol inhalation aerosol with IDC				Albuterol inhalation aerosol without IDC
	Age ≤17 years (N=39,826)	Age 18–39 years (N=39,358)	Age 40+ years (N=56,121)	Total (N=135,305)	Age ≤17 years (N=86,149)	Age 18–39 years (N=85,530)	Age 40+ years (N=115,564)	Total (N=287,243)
Respiratory-related hospitalizations
Patients with hospitalizations, n (%)	405 (1.0)	919 (2.3)	1,452 (2.6)	2,776 (2.1)	940 (1.1)	2,190 (2.6)b	3,337 (2.9)c	6,467 (2.3)d
Number of hospitalizations, mean (SD)	0.01 (0.13)	0.03 (0.17)	0.03 (0.18)	0.02 (0.16)	0.01 (0.12)	0.03 (0.18)b	0.032 (0.20)c	0.02 (0.17)d
Respiratory-related ED visits
Patients with ED visits, n (%)	2,475 (6.2)	3,685 (9.4)	3,484 (6.2)	9,644 (7.1)	6,320 (7.3)a	8,575 (10.0)b	7,994 (6.9)c	22,889 (8.0)d
Number of ED visits, mean (SD)	0.07 (0.28)	0.11 (0.38)	0.07 (0.30)	0.08 (0.32)	0.08 (0.31)a	0.12 (0.39)b	0.08 (0.31)c	0.09 (0.33)d
LRTI OP visits treated with antibiotics
Patients with office visits, n (%)	3,954 (9.9)	4,942 (12.6)	9,119 (16.2)	18,015 (13.3)	9,984 (11.6)a	10,867 (12.7)	18,371 (15.9)	39,222 (13.7)d
Number of office visits, mean (SD)	0.12 (0.38)	0.15 (0.43)	0.20 (0.50)	0.2 (0.45)	0.13 (0.40)a	0.15 (0.43)	0.19 (0.49)c	0.16 (0.45)d
Albuterol HFA prescriptions
Number of patients with >1 albuterol HFA Rx, n (%)	11,888 (29.8)	13,648 (34.7)	21,868 (39.0)	47,404 (35.0)	24,659 (28.6)a	25,522 (29.8)b	39,109 (33.8)c	89,290 (31.1)d
Mean (SD) albuterol HFA Rxs among patients with >1 albuterol HFA Rx	2.45 (0.92)	2.99 (1.53)	2.87 (1.39)	2.80 (1.35)	2.37 (0.78)a	2.74 (1.32)b	2.72 (1.26)c	2.60 (1.18)d

Notes:

a p<0.05 versus patients aged ≤17 years in the albuterol HFA with IDC cohort;

b p<0.05 versus patients aged 18–39 years in the albuterol HFA with IDC cohort;

c p<0.05 versus patients aged 40+ in the albuterol HFA with IDC cohort;

d p≤0.05 versus total patients in the albuterol HFA with IDC cohort.

Abbreviations: ED, emergency department; HFA, hydrofluoroalkane; IDC, integrated dose counter; LRTI, lower respiratory tract infection; OP, outpatient; SD, standard deviation.

Figure 2 Adjusted per-patient number of respiratory-related hospitalizations and ED visits during the 6-month follow-up period.

Notes: Utilization estimates based on the method of recycled predictions using the regression coefficient for albuterol HFA with IDC controlling for demographic and pre-index clinical characteristics and medication use.
Abbreviations: ED, emergency department; HFA, hydrofluoroalkane; IDC, integrated dose counter.

Table 3 Multivariable logistic regression odds ratios for predicting respiratory-related hospitalizations and ED visits during 6-month follow-upa

Effect	Respiratory-related hospitalizations, odds ratio (confidence level)	Respiratory-related ED visits, odds ratio (confidence level)
Albuterol inhalation aerosol metered dose (ref=nonmetered dose)	0.92 (0.88–0.96)b	0.92 (0.90–0.94)c
Demographic variables
Age group 18–39 years (ref=age <18 years)	1.74 (1.62–1.86)c	1.32 (1.29–1.37)c
Age group 40+ years (ref=age <18 years)	1.52 (1.42–1.63)c	0.87 (0.85–0.90)c
Female (ref=male)	1.23 (1.17–1.29)c	1.12 (1.09–1.14)c
Clinical variables (ref=no)
Rhinitis	0.64 (0.60–0.68)c	0.73 (0.71–0.76)c
GERD	1.03 (0.95–1.11)	1.11 (1.05–1.18)b
Eczema	0.82 (0.74–0.92)b	0.97 (0.92–1.03)
Ischemic heart disease	1.26 (1.10–1.46)d	1.10 (0.98–1.25)
Other chronic respiratory disease	1.76 (1.40–2.20)c	1.03 (0.84–1.27)
Oral or injectable corticosteroids	1.06 (1.01–1.12)d	1.15 (1.11–1.18)c
ICS	0.78 (0.69–0.88)c	0.93 (0.87–1.01)
LABA (with ICS)	1.00 (0.92–1.08)	0.90 (0.86–0.95)c
LAMA	0.96 (0.72–1.30)	0.80 (0.63–1.03)
Other respiratory medications (SAMA, LTRA, and other)	0.87 (0.80–0.95)d	0.92 (0.88–0.98)d
No asthma drug therapy	1.13 (1.00–01.29)	1.32 (1.22–1.42)c
Pre-index all-cause total health care costs (log)	1.58 (1.56–1.60)c	1.08 (1.07–1.09)c

Notes:

a Results were controlled for baseline demographics and pre-index clinical characteristics, medication use, and health care costs; all tests were statistically significant at

b p<0.001;

c p<0.0001;

d p<0.05.

Abbreviations: ED, emergency department; GERD, gastroesophageal reflux disease; ICS, inhaled corticosteroid; LABA, long-acting beta agonist; LAMA, long-acting muscarinic antagonist; LTRA, leukotriene receptor antagonist; SAMA, short-acting muscarinic antagonist.