Outcomes associated with initiation of tiotropium or fluticasone/salmeterol in patients with chronic obstructive pulmonary disease

Figures & data

Figure 1 Study population selection and attrition.

Table 1 Demographic and sociodemographic characteristics by index therapy cohort

	Tiotropium (N = 1561)		Fluticasone/salmeterol (N = 2976)		P-value
	N	%	N	%
Age category
40–54	367	23.5	935	31.4	<0.001
55–64	673	43.1	1,161	39.0	0.007
65–74	301	19.3	509	17.1	0.069
75+	220	14.1	371	12.5	0.122
Gender
Male	883	56.6	1,526	51.3	0.001
US census region
Northeast	145	9.3	288	9.7	0.672
Midwest	450	28.8	911	30.6	0.213
South	769	49.3	1,350	45.4	0.012
West	197	12.6	427	14.3	0.108
Household income (USD)
< $30,000	336	21.5	560	18.8	0.030
$30,000–$49,999	306	19.6	543	18.3	0.266
$50,000–$69,999	332	21.3	645	21.7	0.753
$70,000–$99,999	238	15.3	509	17.1	0.109
≥$100,000	247	15.8	528	17.7	0.103
Missing	102	6.5	191	6.4	0.880
Race
White^a	1340	85.8	2484	83.5	0.037
Non-white^b	199	12.8	450	15.1	0.030
Missing	22	1.4	42	1.4	0.996

Notes:

a Non-Hispanic Caucasian;

b Non-white includes Hispanic; African American, Asian, other race/ethnicity.

Table 2 Baseline clinical characteristics by index therapy cohort

	Tiotropium (N = 1561)		Fluticasone/salmeterol (N = 2976)		P-value
	N	%	N	%
Respiratory complication
Present during baseline	202	12.9	380	12.8	0.870
Comorbid conditions
Hypertension	688	44.1	1277	42.9	0.452
Heart disease	703	45.0	1223	41.1	0.011
Disorders of lipid metabolism	613	39.3	1114	37.4	0.226
Respiratory infections	588	37.7	1238	41.6	0.010
Use of breathing agents
Use of short-acting beta-agonist	576	36.9	967	32.5	0.003
Use of corticosteroid	303	19.4	509	17.1	0.054
Use of oxygen	267	17.1	377	12.7	<0.001
Charlson Comorbidity Index score
0	179	11.5	572	19.2	<0.001
1	793	50.8	1397	47.0	0.013
2	298	19.1	510	17.1	0.102
3	148	9.5	275	9.2	0.791
4	78	5.0	104	3.5	0.014
≥ 5	65	4.1	118	4.0	0.746

Figure 2 Unadjusted discontinuation and adherence by index therapy cohort.

Table 3 Unadjusted respiratory-related costs by index therapy cohort

	Tiotropium (N = 1561)		Fluticasone/salmeterol (N = 2976)		P-value
	Mean	SD	Mean	SD
Inpatient stay costs	1646	11,074	1248	8368	0.213
Medical costs	2671	13,334	1958	8956	0.058
Outpatient pharmacy costs	1080	1096	974	1124	0.002
Health care costs	3751	13,462	2932	9137	0.031

Note: All costs were measured in 2006 US dollars and during follow-up period. Inpatient stay costs are costs associated with inpatient facility stays; medical costs are costs for all medical services, including inpatient costs; health care costs are the sum of medical and outpatient pharmacy costs.

Abbreviation: SD, standard deviation.

Table 4 Unadjusted respiratory-related costs by adherence level

	Tiotropium				P-value	Fluticasone/salmeterol				P-value
	Adherent^a(N = 305)		Nonadherent (N = 1256)			Adherent (N = 253)		Nonadherent (N = 2723)
	Mean	SD	Mean	SD		Mean	SD	Mean	SD
Inpatient stay costs	1412	14,523	1703	10,066	0.741	604	2441	1307	8714	0.002
Medical costs	2539	14,897	2703	12,932	0.860	1502	3328	2001	9307	0.070
Outpatient pharmacy costs	2405	1048	759	835	<0.001	3148	1153	772	882	<0.001
Health care costs	4945	15,076	3462	13,030	0.115	4650	3752	2772	9468	0.002

Notes: All costs were measured in 2006 US dollars and during follow-up period. Inpatient stay costs are costs associated with inpatient facility stays; medical costs are costs for all medical services, including inpatient costs; health care costs are the sum of medical and outpatient pharmacy costs.

a Adherent = continuous medication possession ratio ≥0.80

Abbreviation: SD, standard deviation.

Figure 3 Regression-adjusted discontinuation: index therapy cohort.

Notes: Controlled for: age category; gender; baseline respiratory complication; baseline Charlson Comorbidity Index score; household income; race; pulmonologist-prescribed index therapy fill; baseline use of corticosteroid, short-acting beta- agonist, oxygen; baseline hypertension, heart disease, respiratory infection, lipid metabolism disorder.

Figure 4 Regression-adjusted adherence: index therapy cohort.

Notes: Controlled for: age category; gender; baseline respiratory complication; baseline Charlson Comorbidity Index score; household income; race; pulmonologist-prescribed index therapy fill; baseline use of corticosteroid, short-acting beta- agonist, oxygen; baseline hypertension, heart disease, respiratory infection, lipid metabolism disorder.
Abbreviation: MPR, medication possession ratio.

Table 5 Regression-adjusted respiratory-related costs: index therapy cohort and adherence

	Health care costs	Medical costs		Inpatient costs
	Cost ratio (95% CI)	Odds ratio (95% CI)	Cost ratio (95% CI)	Odds ratio (95% CI)	Cost ratio (95% CI)
Cohort (tiotropium = 1)	0.999 (0.831–1.202)	0.925 (0.777–1.102)	1.061 (0.809–1.392)	0.905 (0.724–1.131)	1.175 (0.849–1.627)
Adherent to index therapy (MPR ≥ 0.80)	1.469 (1.131–1.908)^a	1.422 (1.067–1.896)^b	0.629 (0.434–0.912)^b	0.883 (0.648–1.202)	0.466 (0.303–0.719)^a
Observations	4244	4244	3478	4244	441

Notes:

a P < 0.01;

b 0.01≤ P < 0.05. Controlled for: age category; gender; baseline respiratory complication; baseline Charlson comorbidity index score; household income; race; pulmonologist-prescribed index therapy fill; baseline line of corticosteroid, short-acting beta-agonist, oxygen; baseline hypertension, heart disease, respiratory infection, lipid metabolism disorder. All costs were measured in 2006 US dollars and during follow-up period.

Abbreviations: CI, confidence interval; MPR, medication possession ratio.

ICD-9-CM Diagnosis Codes for Respiratory Conditions or Respiratory Failure

Respiratory Condition	ICD-9-CM Code
Acute respiratory infection	466.xx
Pneumonia	480.x–487.0
Chronic bronchitis	490–491.xx
Emphysema	492.x
Bronchiectasis	494.x
Pneumonitis and pneumoconiosis	495.x, 500–508.x
Chronic obstructive pulmonary disease	496
Empyema, pleurisy, and pneumothorax	510.x–512.x
Respiratory failure	518.81–518.84
Abscess of lung and mediastinum	513.x
Pulmonary congestion and hypostasis	514
Post-inflammatory pulmonary fibrosis	515
Other alveolar and parietoalveolar pneumonopathy	516.x
Pulmonary collapse	518.0
Pulmonary eosinophilia	518.3
Acute edema of lung, unspecified	518.4
Pulmonary insufficiency following trauma or surgery	518.5
Allergic bronchopulmonary aspergillosis	518.6
Transfusion-related acute lung injury	518.7
Other diseases of the lung, not elsewhere classified	518.89
Other diseases of the respiratory system	519.xx

Note: Asthma would have been added as a respiratory condition; however, patients with medical claims with diagnosis codes for asthma were excluded from the study population.

ICD-9-CM Diagnosis Codes for Cardiac Conditions

Cardiac Condition	ICD-9-CM Code
Diseases of mitral valve	394.x
Diseases of aortic valve	395.x
Diseases of mitral and aortic valves	396.x
Rheumatic heart failure (congestive)	398.91
Hypertensive heart disease	402.xx
Hypertensive heart and chronic kidney disease	404.xx
Acute myocardial infarction	410.xx
Acute pulmonary heart disease	415.xx
Chronic pulmonary heart disease	416.x
Other diseases of pulmonary circulation	417.x
Other diseases of endocardium	424.xx
Cardiomyopathy	425.x
Heart failure	428.xx
Takotsubo syndrome	429.83