Lung cancer and socioeconomic status in a pooled analysis of case-control studies

Authors	HOVANEC Jan SIEMIATYCKI Jack CONWAY David I. OLSSON Ann STUCKER Isabele GUIDA Florence JOCKEL Karl-Heinz POHLABELN Hermann AHRENS Wolfgang BRUSKE Irene WICHMANN Heinz-Erich GUSTAVSSON Per CONSONNI Dario MERLETTI Franco RICHIARDI Lorenzo SIMONATO Lorenzo FORTES Cristina PARENT Marie-Elise MCLAUGHLIN John DEMERS Paul LANDI Maria Teresa CAPORASO Neil TARDON Adonina ZARIDZE David SZESZENIA-DABROWSKA Neonila RUDNAI Peter LISSOWSKA Jolanta FABIANOVA Eleonora FIELD John DUMITRU Rodica Stanescu BENCKO Vladimir FORETOVÁ Lenka JANOUT Vladimir KROMHOUT Hans VERMEULEN Roel BOFFETTA Paolo STRAIF Kurt SCHUZ Joachim KENDZIA Benjamin PESCH Beate BRUNING Thomas BEHRENS Thomas
Year of publication	2018
Type	Article in Periodical
Magazine / Source	Plos one
MU Faculty or unit	Faculty of Medicine
Citation
Doi	http://dx.doi.org/10.1371/journal.pone.0192999
Keywords	Lung cancer; socioeconomic status
Description	Background An association between low socioeconomic status (SES) and lung cancer has been observed in several studies, but often without adequate control for smoking behavior. We studied the association between lung cancer and occupationally derived SES, using data from the international pooled SYNERGY study. Methods Twelve case-control studies from Europe and Canada were included in the analysis. Based on occupational histories of study participants we measured SES using the International Socio-Economic Index of Occupational Status (ISEI) and the European Socio-economic Classification (ESeC). We divided the ISEI range into categories, using various criteria. Stratifying by gender, we calculated odds ratios (OR) and 95% confidence intervals (CI) by unconditional logistic regression, adjusting for age, study, and smoking behavior. We conducted analyses by histological subtypes of lung cancer and subgroup analyses by study region, birth cohort, education and occupational exposure to known lung carcinogens. Results The analysis dataset included 17,021 cases and 20,885 controls. There was a strong elevated OR between lung cancer and low SES, which was attenuated substantially after adjustment for smoking, however a social gradient persisted. SES differences in lung cancer risk were higher among men (lowest vs. highest SES category: ISEI OR 1.84 (95% CI 1.61-2.09); ESeC OR 1.53 (95% CI 1.44-1.63)), than among women (lowest vs. highest SES category: ISEI OR 1.54 (95% CI 1.20-1.98); ESeC OR 1.34 (95% CI 1.19-1.52)). Conclusion SES remained a risk factor for lung cancer after adjustment for smoking behavior.