Table 1

Baseline Patient Characteristics

Variable

COPD with Anemia (n = 27,932)

Non-anemic COPD (n = 104,492)

P value

Demographics

Age, mean (SD), years

77.5 ± 7.8

74.7 ± 7.6

<0.001

Age distribution (years, %)

65–69

19.0%

31.5%

<0.001

70–74

20.1%

23.0%

75–79

21.4%

18.7%

80–84

18.7%

13.7%

> 84

20.6%

12.1%

Male (%)

34.2%

42.4%

<0.001

Pulmonary Characteristics of Interest Present in the Six Month Baseline Period

Concomitant asthma diagnosis

25.2%

22.6%

<0.001

Use of supplemental oxygen

9.8%

3.7%

<0.001

Comorbidities, % (by ICD-9 coded organ system) Present in the Six Month Baseline Period

Infectious and parasitic

1.7%

1.4%

<0.001

Skin disorders

2.3%

2.2%

NS

Digestive disorders

2.5%

2.5%

NS

Mental disorders

3.3%

2.9%

<0.001

Genitourinary disorders

3.9%

3.3%

<0.001

Blood diseases

4.3%

0.8%

<0.01

Nervous system

4.4%

6.3%

<0.001

Musculoskeletal disorders

7.7%

9.0%

<0.001

Other respiratory disorders

8.3%

8.8%

<0.001

Endocrine and metabolic

8.5%

7.9%

<0.001

Circulatory disorders

26.8%

26.0%

<0.01

Abbreviations: COPD – Chronic obstructive pulmonary disease, NS – not significant

Halpern et al. Cost Effectiveness and Resource Allocation 2006 4:17   doi:10.1186/1478-7547-4-17