Chronic obstructive pulmonary disease as a risk factor for lung cancer

Table 1 Major causes of death reported in patients with chronic obstructive pulmonary disease

Author	Publication year	Total No. of COPD	Total deaths	Cause of death (%)1
				COPD2	Lung cancer	Other cancer	Cardiovascular	Others
Vilkman et al[14]	1997	2237	1070	30	12	8	33	17
Garecka et al[11]	1997	135	70	61	4	4	6	24
Antonelli Incalzi et al[8]	1997	270	228	63	5	4	16	12
Zielinski et al[15]	1997	215	215	49	7	ND	37	7
Keistinen et al[12]	1998	2727	973	22	13	8	32	25
Pauwel et al[13]	1999	1277	18	6	33	6	39	17
Garcia-Aymerich et al[10]	2003	340	98	74	5	2	12	6
Celli et al[9]	2004	625	162	61	12	ND	14	13
Anthonisen et al[16]	2005	5887	731	8	33	21	22	16

¹Calculated from the data reported by each literature;

²Including respiratory causes, respiratory failure, respiratory infection. Pulmonary embolism was included in cardiovascular cause. ND: Not described; COPD: Chronic obstructive pulmonary disease.

Table 2 Odds ratios for coincidental lung cancer based on factors indicative of hronic obstructive pulmonary disease or interstitial lung diseases, according to smoking status¹

	Never smoker (n = 284)	Ex-smoker (n = 101)	Current smoker (n = 179)	Total (n = 564)
FEV1/FVC < 70%	10.42 (2.82-38.55)3	5.89 (2.02-17.22)	7.456 (3.48-15.95)	7.17 (4.03-12.74)
%VC < 80%	2.02 (0.42-9.86)	No data4	2.25 (0.62-8.11)	4.73 (2.00-11.17)
LAA score ≥ 12	0.98 (0.21-4.43)	3.43 (1.50-7.85)	5.07 (2.51-10.28)	3.63 (2.24-5.89)
Fibrosis score ≥ 1	6.39 (2.13-19.18)	3.94 (1.20-12.88)	5.45 (2.39-12.44)	5.10 (2.82-9.24)
GGA score ≥ 1	2.32 (0.80-6.71)	3.59 (1.09-11.80)	2.48 (1.06-5.77)	2.71 (1.52-4.81)

¹See the reference by Mizuno et al[24] for details;

²Low attenuation area (LAA) was assesed using Goddard's scoring system: fibrosis and ground glass attenuation (GGA) were assessed using Kazzerooni's scoring system;

³Numbers in parentheses indicate 95%CI;

⁴No data calculated because of insufficient number.