Table 1 Baseline characteristics and comorbidities of the study patients according to sex

Age (median, IQR)

72.32 ± 10.39

71.86 ± 10.23

74.02 ± 10.79

< 0.001

BMI (kg/m²)

21.58 ± 4.07

21.38 ± 3.88

22.44 ± 4.69

< 0.001

BMI<18(kg/m²)

1517(19.4)

1270(20.0)

247(17.0)

0.009

Smoker( n, %)

8652(61.8)

8351(75.8)

301(10.1)

< 0.001

 Pack-years

39.44 ± 26.57

39.92 ± 26.64

25.31 ± 19.76

< 0.001

 Current smoker (n, %)

2738(19.6)

2632(23.9)

106(3.6)

< 0.001

 Former smoker (n, %)

5914(42.7)

5719(52.4)

195(6.6)

< 0.001

Frequency of hospitalization due to

AECOPD in the past year (times), (n, %)

0.284

 <2

4221(71.0)

3440(70.7)

781(72.3)

 ≥ 2

1726(29.0)

1427(29.3)

299(27.7)

FEV₁/FVC (%)

52.65 ± 13.45

51.00 ± 13.62

57.27 ± 11.82

< 0.001

FEV₁/% predicted (%)

48.19 ± 23.85

44.72 ± 21.77

59.03 ± 26.80

< 0.001

Comorbidities (n, %)

Coronary heart disease

1546(11.0)

1219(11.1)

327(10.9)

0.860

Heart failure

1609(11.5)

1153(10.5)

456(15.3)

< 0.001

Heart valve problems

250(1.8)

186(1.7)

64(2.1)

0.096

Arrhythmia

1187(8.5)

871(7.9)

316(10.6)

< 0.001

Pulmonary tuberculosis

635(4.5)

564(5.1)

71(2.4)

< 0.001

Bronchiectasis

1198(8.6)

815(7.4)

383(12.8)

< 0.001

ILD

403(2.9)

326(3.0)

77(2.6)

0.270

Asthma

462(3.3)

286(2.6)

176(5.9)

< 0.001

OSAHS

84(0.6)

62(0.6)

22(0.7)

0.275

Chronic pulmonary heart disease

2905(20.7)

2092(19.0)

813(27.2)

< 0.001

Hypertension

4679(33.4)

3514(31.9)

1165(39.0)

< 0.001

Diabetes

1804(12.9)

1306(11.9)

498(16.7)

< 0.001

Stroke

784(5.6)

615(5.6)

169(5.7)

0.871

Venous thromboembolism

520(3.7)

359(3.3)

161(5.4)

< 0.001

Active cancer

800(5.7)

667(6.1)

133(4.5)

0.001

Chronic renal insufficiency

514(3.7)

376(3.4)

138(4.6)

0.002

Anxiety-depression

106(0.8)

69(0.6)

37(1.2)

0.001

No. of comorbidities

1.84 ± 1.60

1.73 ± 1.57

2.23 ± 1.65

< 0.001