Impact of Chronic Obstructive Pulmonary Disease on the Mortality of Patients with Small Cell Lung Cancer

Figures & data

Table 1 Baseline Characteristics of the Study Population

	Non-COPD N=2334	COPD N=4235	p-value
Age	65.69±11.47	71.37±10.68	<0.0001
Age group, years			<0.0001
20–59	746 (31.96)	675 (15.94)
60–75	1045 (44.77)	1800 (42.5)
>75	543 (23.26)	1760 (41.56)
Sex			0.1473
Male	2087 (89.42)	3834 (90.53)
Female	247 (10.58)	401 (9.47)
Lung cancer stage			<0.0001
Stage 1	23 (0.99)	112 (2.64)
Stage 2	22 (0.94)	63 (1.49)
Stage 3	477 (20.44)	1061 (25.05)
Stage 4	1595 (68.34)	2547 (60.14)
Unknown	217 (9.3)	452 (10.67)
BMI	23.41±3.78	23.59±3.93	0.2294
Smoking (former and current)	2143 (91.82)	3954 (93.36)
Follow-up period (mean±SD, years)	0.92±1.25	0.94±1.24
Comorbidities
Congestive heart failure	95 (4.07)	542 (12.8)	<0.0001
Peripheral vascular disease	64 (2.74)	214 (5.05)	<0.0001
Cerebrovascular disease	387 (16.58)	1078 (25.45)	<0.0001
Dementia	53 (2.27)	182 (4.30)	<0.0001
Connective tissue disease	25 (1.07)	122 (2.88)	<0.0001
Peptic ulcer disease	756 (32.39)	2025 (47.82)	<0.0001
Chronic liver disease	326 (13.97)	752 (17.76)	0.0001
Diabetes	563 (24.12)	1176 (27.77)	0.0013
Old cerebrovascular disease	50 (2.14)	101 (2.38)	0.5300
Chronic kidney disease	137 (5.87)	442 (10.44)	<0.0001
Death	2239 (95.93)	4077 (96.27)	0.4938

Abbreviations: BMI, body mass index; COPD, chronic obstructive pulmonary disease.

Table 2 Baseline Characteristics of the Matched Study Population

	Non-COPD N=1457	COPD N=1457	p-value
Age	68.67±9.84	68.98±9.83	0.4007
Age group, years			0.7251
20–59	307 (21.07)	290 (19.90)
60–75	723 (49.62)	738 (50.65)
>75	427 (29.31)	429 (29.44)
Sex			>0.9999
Male	1399 (96.02)	1399 (96.02)
Female	58 (3.98)	58 (3.98)
Lung cancer stage			>0.9999
Stage 1 and 2	6 (0.41)	6 (0.41)
Stage 3	279 (19.15)	279 (19.15)
Stage 4	1085 (74.47)	1085 (74.47)
Unknown	87 (5.97)	87 (5.97)
Follow-up period (mean±SD, years)	0.80±1.09	0.90±1.15
BMI	23.31±3.65	23.89±3.95	0.0040
Smoking (former and current)	1356 (93.07)	1370 (94.03)	0.2911
Comorbidities
Congestive heart failure	64 (4.39)	158 (10.84)	<0.0001
Peripheral vascular disease	50 (3.43)	72 (4.94)	0.0419
Cerebrovascular disease	290 (19.90)	334 (22.92)	0.0469
Dementia	42 (2.88)	45 (3.09)	0.7440
Connective tissue disease	15 (1.03)	31 (2.13)	0.0174
Peptic ulcer disease	497 (34.11)	657 (45.09)	<0.0001
Chronic liver disease	193 (13.25)	272 (18.67)	0.0001
Diabetes	371 (25.46)	422 (28.96)	0.0338
Old cerebrovascular disease	37 (2.54)	31 (2.13)	0.4616
Chronic kidney disease	102 (7.00)	134 (9.20)	0.0298
Death	1419 (97.39)	1410 (96.77)	0.3218

Abbreviations: BMI, body mass index; COPD, chronic obstructive pulmonary disease.

Table 3 Multivariable Cox Proportional Hazards Model Analysis for the Risk of Death

	Univariate	p-value	Multivariate	p-value
	HRs		HRs
COPD vs Non-COPD	0.89 (0.83–0.96)	0.0018	0.92 (0.82–1.02)	0.1214
Age	1.04 (1.03–1.04)	<0.0001	1.03 (1.02–1.04)	<0.0001
Male vs Female	0.93 (0.77–1.12)	0.4292	1.27 (0.97–1.67)	0.084
Lung cancer stages
Stage 1	0.28 (0.23–0.34)	<0.0001	0.19 (0.13–0.26)	<0.0001
Stage 2	0.35 (0.28–0.45)	<0.0001	0.28 (0.19–0.41)	<0.0001
Stage 3	0.51 (0.48–0.55)	<0.0001	0.47 (0.43–0.52)	<0.0001
Stage 4	REF.		REF.
Unknown	0.69 (0.63–0.75)	<0.0001	0.61 (0.42–0.90)	0.0121
BMI	0.94 (0.93–0.96)	<0.0001	0.95 (0.93–0.96)	<0.0001
Smoking (former and current)	0.92 (0.79–1.07)	0.2709	1.04 (0.87–1.25)	0.6447
Comorbidities
Congestive heart failure	1.46 (1.27–1.68)	<0.0001	1.35 (1.11–1.64)	0.0024
Peripheral vascular disease	1.41 (1.18–1.70)	0.0002	1.22 (0.91–1.63)	0.1746
Cerebrovascular disease	1.35 (1.24–1.48)	<0.0001	1.13 (0.97–1.30)	0.1086
Dementia	1.76 (1.42–2.19)	<0.0001	1.36 (0.97–1.91)	0.0722
Connective tissue disease	0.92 (0.68–1.24)	0.5908	0.83 (0.57–1.22)	0.3491
Peptic ulcer disease	1.10 (1.02–1.19)	0.0126	0.96 (0.85–1.07)	0.4363
Chronic liver disease	0.98 (0.89–1.08)	0.6853	0.97 (0.83–1.13)	0.6976
Diabetes	1.19 (1.10–1.30)	<0.0001	1.25 (1.08–1.44)	0.0022
Old cerebrovascular disease	1.31 (1.03–1.67)	0.0288	1.13 (0.75–1.71)	0.5625
Chronic kidney disease	1.39 (1.22–1.59)	<0.0001	1.19 (0.98–1.44)	0.0772

Abbreviations: BMI, body mass index; COPD, chronic obstructive pulmonary disease; HRs, hazard ratios.

Figure 1 Flowchart of the study patients with newly diagnosed small cell lung cancer with and without COPD.

Figure 2 Survival probability of COPD and non-COPD cohorts.