Economic burden of COPD in a Swedish cohort: the ARCTIC study

Figures & data

Table 1 Patient demographics of the COPD population and the age- and sex-matched reference population

Variablea	COPD patients (n=17,479)	Reference population (n=84,514)	p-value
Age (years)
Mean (SD)	65.0 (11.90)	65.0 (11.90)
Sex
Female, n (%)	9,881 (56.53)	47,777 (56.53)
Male, n (%)	7,598 (43.47)	36,737 (43.47)
Health care utilization
Outpatient visits per year	1.78	1.50	<0.0001
Number of PC contacts per year	10.0	4.83	<0.0001
Patients with overnight stays, n (%)	6,042 (34.57)	19,497 (23.09)	<0.0001
Patients with outpatient hospital visits, n (%)	10,575 (60.50)	48,657 (57.61)	<0.0001
Days of sick leave in 2013, meanb	30.3	16.4
People in receipt of social welfare in 2013, %	67.5	39.8
Number of Charlson comorbidity groups	1.60	1.27	<0.0001
Charlson Comorbidity Index value	1.70	1.33	<0.0001
Comorbidities, n (%)
Asthma	2,531 (14.48)	4,077 (4.83)	<0.0001
Cardiovascular diseasesc	6,736 (38.54)	19,572 (23.17)	<0.0001
Ischemic heart diseasesd	1,815 (10.38)	4,111 (4.87)	<0.0001
Hypertensive diseasese	4,019 (22.99)	11,693 (13.85)	<0.0001
Other forms of heart diseasesf	2,504 (14.33)	5,388 (6.38)	<0.0001
Hyperlipidemia	385 (2.20)	976 (1.16)	<0.0001
Diabetes, type I	340 (1.95)	1,420 (1.68)	0.0148
Diabetes, type II	1,253 (7.17)	3,859 (4.57)	<0.0001
Depression	962 (5.50)	2,178 (2.58)	<0.0001
Osteoporosis	397 (2.27)	866 (1.03)	<0.0001
Fractures	1,126 (6.44)	4,069 (4.82)	<0.0001
Respiratory diseasesg	6,382 (36.51)	11,150 (13.20)	<0.0001
Medication use during follow-up, n (%)
Beta-blocking agents	4,401 (25.18)	14,834 (17.56)	<0.0001
Antidepressants	3,418 (19.55)	9,906 (11.73)	<0.0001
Statins	3,228 (18.47)	12,786 (15.14)	<0.0001
Diabetes medication	1,565 (8.95)	5,869 (6.95)	<0.0001
Antibiotic for airways	5,273 (30.17)	12,213 (14.46)	<0.0001
Oral steroids	3,116 (17.83)	6,250 (7.40)	<0.0001
Low-dose ICSh	5,132 (29.36)	10,619 (12.56)	<0.0001
High-dose ICSh	2,927 (16.75)	4,170 (4.93)	<0.0001

Notes:

a Variables quoted for 2 years prior to COPD diagnosis date unless otherwise stated.

b Denotes number of days of sick leave in addition to the first 14 days of sick leave paid for by an employer.

c Includes diseases of the circulatory system, I00–I99.

d Includes but not limited to angina pectoris, acute myocardial infarction, other acute ischemic heart diseases, and chronic ischemic heart diseases, I20–I25.

e Includes hypertensive heart disease, hypertensive renal disease, hypertensive heart and renal disease, primary hypertension, and secondary hypertension, I10–I15.

f Includes but not limited to heart failure, atrial fibrillation and flutter, other cardiac arrhythmias, cardiac arrest, and cardiomyopathy, I30–I52.

g Includes diseases of the respiratory system, J00–J99.

h Low-dose ICS, <640 μg budesonide or equivalent/day; high-dose ICS, >640 μg budesonide or equivalent/day.

Abbreviations: SD, standard deviation; PC, primary care; ICS, inhaled corticosteroid.

Table 2 Direct costs per patient (in euros [€]) stratified by the COPD and reference populations during 2013

Cost category	COPD patients (n=7,251)	Reference population (n=41,111)
Respiratory drugs	584	50
All drugs	438	206
Hospital nights (COPD related)	620	68
Hospital nights (non-COPD)	8,295	1,285
Hospital visits (COPD related)	34	4
Hospital visits (non-COPD)	1,245	589
PC visits (physician)	1,453	402
PC visits (non-physician)	510	112
Total	13,179	2,716

Notes: All costs were significantly higher for COPD patients compared to reference population (all p-values <0.0001). Unit costs are (SEK, 2013 rates) 9,580 SEK for hospital nights, 3,000 SEK for hospital visits, and 1,462 SEK for physician and 596 SEK for non-physician PC visits. Exchange rate in 2013: 8 SEK =1 euro.

Abbreviations: PC, primary care; SEK, Swedish krona.

Figure 1 HCRU in euros (€), stratified by COPD patients and reference patient population during 2013.

Note: HCRU was significantly higher for COPD patients compared to the reference population (all p-values <0.0001).

Abbreviations: HCRU, health care resource utilization; PC, primary care.

Figure 2 HCRU in euros (€), stratified by disease severity during 2013.

Notes: Disease severity defined using GOLD 2009 and 2014 treatment guidelines: mild COPD, FEV₁ ≥80%; moderate COPD, 50%≤ FEV₁ <80%; severe COPD, 30%≤ FEV₁ <50%; and very severe COPD, FEV₁ <30%. All costs increased significantly with COPD disease severity (all p-values <0.0001).
Abbreviations: HCRU, health care resource utilization; GOLD, Global Initiative for Chronic Obstructive Lung Disease; FEV₁, forced expiratory volume in 1 second; PC, primary care.

Figure 3 Estimated direct and indirect costs in euros (€) stratified by age group during 2013 in COPD patients.

Abbreviation: PC, primary care.

Figure 4 Yearly direct costs (euros [€]/year) stratified by frequent and non-frequent exacerbator phenotype (sum of drug costs and primary and secondary care costs).

Note: Frequent exacerbator (≥2 exacerbations per year) and non-frequent exacerbator (<2 exacerbations per year).

Figure 5 Yearly income in euros (€; A), number of sick days per year (B), and proportion of patients receiving social welfare each year (C), stratified by the COPD and reference patient populations.

Note: Social welfare included health insurance, benefits in respect of accidents at work or occupational diseases, disability benefits, old-age and survivors’ benefits, unemployment insurance and family benefits, compensation for unemployment, sick leave support, early retirement, and support to rent an apartment.

Table 3 Exacerbation costs (in euros [€]) per occurrence and non-exacerbation-related maintenance costs during 2013

GOLD 2010 classification of airflow limitation	Cost per moderate exacerbationa		Cost per severe exacerbationb	Annual non-exacerbation-related maintenance costs
	No of exacerbations per group	Mean (SD), €	No of exacerbations per group	Mean (SD), €	Mean, €
Mild COPD (n=1,041)	852	532 (808)	24	5,475 (4,975)	6,474
Moderate COPD (n=3,596)	3,188	631 (1,035)	224	5,988 (6,120)	6,878
Severe COPD (n=1,950)	2,139	614 (825)	330	5,992 (5,951)	6,674
Very severe COPD (n=564)	775	557 (817)	191	8,320 (8,928)	7,523

Notes: Exchange rate in 2013, 8 SEK =1 euro; recurrent exacerbations occurring within 14 days were considered as one unique event.

a Moderate exacerbation is defined by visits to PC (ICD-10: J44) and/or collection of oral corticosteroids (ATC H02AB) or antibiotics targeted at respiratory diseases (ATC J01AA/J01CA). Moderate exacerbation cost comprises outpatient visits, nurse visits, physician visits, oral corticosteroids, and antibiotics targeted at respiratory diseases during 14 days after the exacerbation occurrence.

b Severe exacerbation is defined as hospitalization due to COPD exacerbation in secondary care (ICD-10: J44.1) and/or emergency hospital visits (J44.1). Severe exacerbation cost comprises cost of hospital nights, outpatient visits, nurse visits, physician visits, oral corticosteroids, and/or antibiotics targeted at respiratory diseases during 14 days after the exacerbation occurrence.

Abbreviations: GOLD, Global Initiative for Chronic Obstructive Lung Disease; SD, standard deviation; SEK, Swedish krona; PC, primary care; ICD-10, International Classification of Diseases, tenth edition; ATC, Anatomic Therapeutic Chemical.