Alcohol consumption and risk of lung cancer: a pooled analysis of cohort studies.
BACKGROUND
Although smoking is the primary cause of lung cancer, much is unknown about lung cancer etiology, including risk determinants for nonsmokers and modifying factors for smokers.


OBJECTIVE
We hypothesized that alcohol consumption contributes to lung cancer risk.


METHODS
We conducted a pooled analysis using standardized exposure and covariate data from 7 prospective studies with 399,767 participants and 3137 lung cancer cases. Study-specific relative risks (RRs) and CIs were estimated and then combined to calculate pooled multivariate RRs by using a random-effects model.


RESULTS
We found a slightly greater risk for the consumption of > or = 30 g alcohol/d than for that of 0 g alcohol/d in men (RR: 1.21; 95% CI: 0.91, 1.61; P for trend = 0.03) and in women (RR: 1.16; 95% CI: 0.94, 1.43; P for trend = 0.03). In male never smokers, the RR for consumption of > or = 15 g alcohol/d rather than 0 g alcohol/d was 6.38 (95% CI: 2.74, 14.9; P for trend < 0.001). In women, there were few never-smoking cases and no evidence of greater risk (RR: 1.35; 95% CI: 0.64, 2.87). Because of possible residual confounding by smoking, we performed sensitivity analyses by reclassifying the never smokers in the highest drinking category as former smokers. Resulting associations for alcohol consumption were somewhat attenuated, but P for trend = 0.05 for men, which was near the original P = 0.03.


CONCLUSIONS
A slightly greater risk of lung cancer was associated with the consumption of > or = 30 g alcohol/d than with no alcohol consumption. Alcohol consumption was strongly associated with greater risk in male never smokers. Residual confounding by smoking may explain part of the observed relation.
Freudenheim
Jo L
JL
Department of Social and Preventive Medicine, University at Buffalo, State University of New York, Buffalo, NY 14214, USA. jfreuden@buffalo.edu
Ritz
John
J
Smith-Warner
Stephanie A
SA
Albanes
Demetrius
D
Bandera
Elisa V
EV
van den Brandt
Piet A
PA
Colditz
Graham
G
Feskanich
Diane
D
Goldbohm
R Alexandra
RA
Harnack
Lisa
L
Miller
Anthony B
AB
Rimm
Eric
E
Rohan
Thomas E
TE
Sellers
Thomas A
TA
Virtamo
Jarmo
J
Willett
Walter C
WC
Hunter
David J
DJ
D000428:Alcohol Drinking / Q000009:adverse effects* / Q000453:epidemiology; D015331:Cohort Studies; D016001:Confidence Intervals; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000139:chemically induced / Q000453:epidemiology*; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology
D000431:Ethanol