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Published by the International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon cedex 08, France @ International Agency for Research on Cancer, 1998 Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Convention. For rights of reproduction or translation of WHO publications, in part or in toto, application should be made to the Office of Publications, World Health Organization, Geneva, Switzerland. The World Health Organization welcomes such applications. The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Health Organization concerning the legal status of any country, territory, city, or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or of certain manufacturers' products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The authors alone are responsible for the views expressed in this publication. Distributed on behalf of the International Agency for Research on Cancer by the Secretariat of the World Health Organization. IARC Library Cataloguing in Publication Data European multicentre case-control study of lung cancer in non-smokers : detailed results on exposure to environmental tobacco smoke ! Paolo Boffetta ... let al.] (larc technical report ; 33) 1. Lung Neoplasms 2. Neoplasms - epidemiology 3. Tobacco Smoke Pollution f. Boffetta, Paolo. II. Title Ill. Series ISBN 92 832 2405 1 (NLM Classification: W1) 100 Printed in France

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ETS exposure The questionnaire on ETS exposure was organized in five sections: (1) exposure during childhood (2) exposure from spouses and other cohabitants during adulthood (3) exposure at the workplace (4) exposure in vehicles (5) exposure in public settings. The amount of information we obtained varied between sections and was greater in sections (1), (2) and (3) than in the other ones. The questionnaire was based on a similar tool used in an international study of urinary cotinine and ETS [Riboli et af., 19901. A copy of the questionnaire is presented in section 2.2. 1.2.3 ETi S Exposure Variables The following circumstances of ETS exposure were considered separately: - childhood (parents and other adults in the house during age 0-18) - spouse - spouse and other cohabitants during adulthood (above age 18) - workplace - spouse and workplace combined - vehicles - other indoor settings In preliminary analyses, we also considered (i) ETS exposure in childhood after excluding subjects exposed during adulthood; (ii) separate analyses of ETS exposure during age 1-10 and 11-18; (iii) ETS from spouse only among subjects who were ever married; and (iv) combined ETS exposure from vehicles and other indoor settings. These analyses, however, did not add to the interpretation of the results and are not presented here. For each exposure circumstance several qualitative and quantitative exposure variables were derived from the information collected in the questionnaire. They are summarized in Table 2.1.2 and described in detail in section 2.2. 1.2.4 Statistical Analysis Odds ratios and 95 percent confidence intervals were calculated based on logistic regression models. We fitted five regression models including, in addition to the exposure variables, different potential confounders:

2.3.3 ETS from spouse .......................................................................................i27 S1 EV: Ever exposed 31TP: Exposure to different tobacco products S1 UD: Duration (years) (non overlapping) S1 DH: Duration (hours/day x years) S1 CU: Cumulative exposure (packs/day x years) S1AV: Average exposure (cigarettes/day) S1 CS: Cumulative exposure of smoking spouse (packs/day x years) SiTS: Time since last ETS exposure (years) 2.3.4 E T S from spouse and other cohabitants ...................................................181 S3EV: Ever exposed S3TP: Exposure to different tobacco products S3UD: Duration (years) (non overlapping) S3CU: Cumulative exposure (packs/day x years) S3AV: Average exposure (cigarettes/day) S3TS: Time since last ETS exposure (years) 2.3.5 ETS from workplace ..................................................................................219 WOEV: Ever exposed WOUD: Duration (years) (non overlapping) WOH: Duration (hours) (non overlapping) WOWD: Weighted duration (hours x level) WOTS: Time since last ETS exposure (years) 2.3.6 ETS from spouse and workplace .............................................................. 255 SWEV: Ever exposed SWUD: Duration (years) (non overlapping) SWDH: Duration (hours/day x years) SWTS: Time since last ETS exposure (years) 2.3.7 ETS from vehicles ..................................................................................... 283 VEEV: Ever exposed VEUD: Duration (years) (non overlapping) VEWD: Weighted duration (days x level) 2.3.8 ETS from other indoor settings ................................................................. 305 INEV: Ever exposed INUD: Duration (years) (non overlapping) INWD: Weighted duration (days x level) 2.4 Additional results ................................................................................................327 2.4.1 Test of Interaction terms 2.4.2 Comparison of conditional and unconditional logistic regression analysis 2.4.3 Test of heterogeneity of results among centres 2.4.4 Test for trend and dose response analysis, p-vaiues 2.4.5 Scatter plots: ETS during childhood ETS from spouse ETS from spouse and other cohabitants N ~ ETS from workplace ~ ~ ETS from spouse and workplace ~ ETS from vehicles ~ ~ ETS from other indoor settings ~ 0 11

1.1: introduction 1.1.1 Aims This report presents the detailed results on environmental tobacco smoke (ETS) of the analysis of the IARC European case-control study of lung cancer in non-smokers. The purpose of the presentation of the detailed results is to allow any interested person to access the many results produced that cannot be presented in scientific journals. The report is not intended to discuss in detail the interpretation of the results: this is done in a series of articles dealing with the various aspects of the results, both at the national and the international level [Boffetta et al., 1998; Nyberg et af., 1998a; Jockei et af., 1998]. 1.1.2 Scope The iARC case-control study of lung cancer in non-smokers also investigates risk factors other than ETS, namely occupational exposures, sources of indoor air pollution other than ETS, and dietary factors. This report presents only the detailed results for variables related to ETS exposure. 1.1.3 Outline The report includes a presentation of the questionnaire on ETS exposure used in the study, a description of the ETS exposure variables derived for the study, a description of the common database, and detailed tables of results. For each i= T S exposure variable, results are presented for the whole data set, for each centre and for several subgroups of cases and controls. For each set of results, we report the number of unexposed and exposed cases and controls, the odds ratios (ORs) and 95 percent confidence intervals iCis) based on various logistic regression models [Breslow and Day, E 980], the number of cases and controls with missing values and, for quantitative variables, the p-value of the test for linear trend. The tables represent a selection of the results produced during the analysis. Additional, usually computationally more complex, approaches were attempted but in most cases did not provide results different from those presented here. For example, for all quantitative variables of ETS exposure (see below), categories were re-calculated based on the centre-specific distribution rather than on the distribution of the pooled set of controls: the results of the two approaches were remarkably similar. Similarly, we treated the exposure variables continuously rather than categorically. We also performed analyses based on lagged ETS exposure and time windows: again, the results were very close to those of the corresponding uniagged and unrestricted analyses.

Exposure to_ ETS in vehicles and indoor settings (sections 2.3.7 and 2.3.8) i he results on two further sources of exposure to i= i"S, vehicles and public indoor settings, were not consistent among the centres. The range of centre-specific ORs for exposure in vehicles (based on a total of 125 exposed cases and 310 exposed controls) ranged from 0 to 2.85, with an overall estimate of 1.14 (CI 0.88-1.48). The range of estimates for ETS exposure in public indoor settings, such as restaurants (174 exposed cases and 454 exposed controls) was 0.24-2.32, with an overall estimate of 1.03 (CI 0.82-1.29). Analyses by duration of exposure did not suggest any consistent pattern for either of these two sources of ETS exposure.

Table of Contents ....................................................................................... iii List of contributors and affiliations "' Acknowiedgements .................................................................................................... ......... iii 1. Text .................................................................................................... ............................1 1.1 introciuction .................................................................................................... ........ 3 1.2 Methods .................................................................................................... ............. 4 1.3 Results .................................................................................................... ............... 8 1.4 References .................................................................................................... .......12 2. Tables .................................................................................................... ....................... e 3 2.1 Descriptive tables .................................................................................................15 2.1.1 Selected characteristics of study areas and design of study 2.1.2 ETS exposure variables 2.1.3 Missing information on potential confounders included in the regression models by centre 2.1.4 Number of cases and controls by centre 2.1.5 Distribution of subjects by centre and gender 2.1.6 Distribution of subjects by age, centre and gender 2.1.7 Mean age of subjects by centre and gender 2.1.8 Distribution of subjects by educational level, centre and gender 2.1.9 Distribution of cases by histological type, centre and gender 2.2 ETS questionnaire and description of exposure variables ................................... 27 ETS questionnaire Weights Occasional smoking ETS during childhood ETS from spouse ETS from spouse and other cohabitants ETS from workplace ETS from spouse and workplace ETS from vehicles ETS from other indoor settings 2.3 Risk estimates and descriptive statistics .............................................................. 47 2.3.1 Occasional smoking ....................................................................................49 OSTR: Ever tried to smoke OSOC: Ever smoked occasionally OSUD: Duration (years) (non overlapping) OSCU: Cumulative exposure (packs/lifetime) 2.3.2 ETS during childhood ..................................................................................73 01 EV: Ever exposed C1 EM: Ever exposed to mother C1 EF: Ever exposed to father C,1TP: Exposure to different tobacco products C1 UN: Number of smokers d1 WN: Weighted number of smokers Di US: Smoking parent years C1 WS: Weighted smoking parent years 01 UD: Duration (years) (non overlapping) C1 WD: Weighted duration (years)

1.3: Results 1.3.1 Presentation of Detailed Results The presentation of the detailed results consists mainly of tables (section 2.3) with descriptive statistics and risk estimates for the 1= s S exposure variables, organized in the following sections (the codes of each section used in naming the variables are given in parentheses): - Occasional smoking (OS) - Childhood exposure during 0-18 years of age (Cl) - Exposure from the spouse (Si) - Exposure from the spouse and other cohabitants (S3) - Exposure at the workplace (WO) - Exposure from the spouse or at the workplace (SW) - Exposure in vehicles (VE) - Exposure in other indoor settings (IN) Additional tables (section 2.4) present additional results for selected variables on heterogeneity among centres (analyses based on continuous variables) and scatter plots. g.3.2 Summary of the Main Results i he database for the analysis contained 650 cases and 1542 controls (table 2.1.4). Two of the German centres and the centres in Sweden, France and Spain contributed the largest numbers of cases. Approximately 22 percent of cases and 35 percent of controls were men. The distribution of age was very similar among cases and controls: mean age was 58 in male cases and 59 in male controls; corresponding figures for women were 62 and 62 (tables 2.1.5, 2.1.6, 2.1.7). The distribution of study subjects by education is shown in table 2.1.8, that of cases by histology in table 2.1.9. Occasional smokina (section 2.3.1) Fifteen cases and 130 controls reported that they ever tried to smoke, resulting in a significantly decreased OR (this information was missing for 170 cases and 454 controls). No overall increase in risk was present for occasional smoking of less than 400 cigarettes in total; a small excess, however, was found for squamous cell carcinoma, with the suggestion of a trend by cumulative exposure but not for duration of exposure. Childhood E i S ex osure (section 2.3.2) A total of 389 cases and 1021 controls reported exposure to ETS during childhood, and the overall OR was 0.78 (Cl 0.64-0.96). In all but three centres the OR was below 1. Subjects' fathers were more likely to be smokers than subjects' mothers were. The risk estimate was similar for exposure to ETS from the father and the mother; the estimated OR for ETS from

T ahie 2.1.3 Missing information on potential confounders included in the regression models, by center I France Germany 1 Germany 2 Germany 3 Italy I Italy 2 Italy 3 Portugal I Spain Sweden Urban residence Education Missing Note: Information on exposure to occupational carcinogens was available in all centers

List of Contributors and their Affiliations Paolo Boffetta (1), Antonio Agudo (2), Wolfgang Ahrens (3,4), Ellen Benhamou (5), Simone Benhamou (6), Sarah C. Darby (7), Gilles Ferro (1), Cristina Fortes (8), Carlos A. Gonzalez (2), Karl-Heinz Jbckei (3), Martin Krauss (1,9), Lothar Kreienbrock (9), Michaela Kreuzer (9), Anabela Mendes (10), Franco Merletti (11), Fredrik Nyberg (12), Goran Pershagen (12), Hermann Pohlabeln (4), Elio Riboli (1), Giovanni Schmid (13), Lorenzo Simonato (14), Jean Tredaniel (15), Elise Whitley (7), Heinz-Erich Wichmann (9), Carlos Winck (16), Paoia Zambon (13), Rodolfo Saracci (1, 17) 1. International Agency for Research on Cancer, Lyon, France 2. Institute for Epidemiological and Clinical Research, Matarb, Spain 3. Institute for Medical Informatics, Biometry and Epidemiology, Essen, Germany 4. Bremen Institute for Prevention Research, Bremen, Germany 5. Institute Gustave Roussy, Paris, France 6. National Institute of Health and Medical Research, Paris, France 7. Imperial Cancer Research Fund, Oxford, United Kingdom 8. Epidemiology Unit Latium Region, Rome, Italy 9. GSF Institute for Epidemiology, Munich, Germany 10. Regional Health Administration, Lisbon, Portugal 11. Unit of Cancer Epidemiology, University of Turin, Turin, Italy 12. Karolinska Institute, Stockholm, Sweden 13. Forianini Hospital, Rome, Italy 14. Venetian Cancer Registry, Padua, Italy 15. St Louis Hospital, Paris, France 16. Hospital Viana do Castelo, Viana do Castelo, Portugal 17. National Research Council, Pisa, Italy Acknowledgements The study was partially supported by the following grants: IARC: European Commission DG-XII (Contract No. EV5V-CT94-0555) for the coordination France: Association pour Ia Recherche sur ie Cancer; European Commission (90CVV01018); Caisse Nationale d'Assurance Maladie des Travailleurs Sociaux Germany 1: Federal Ministry for Education, Science, Research and Technology (grant No. 01 HK 546); Federal Ministry of Work and Social Affairs (grant No. IIIb 7-2.'/13) Germany 2: Federal Office of Radiation Protection, Salzgitter (grant No. St Sch 1066, 4047, 4074/1) Germany 3: Federal ®ffice of Radiation Protection, Salzgitter (grant No. St Sch 4006, 4112) Italy 1: MURST; Italian Association for Cancer Research (AIRC); Regione Piemonte- Ricerca Finalizzata Italy 2: National Research Council (contract No. 91.00327.CT04); Italian Association for Cancer Research (AIRC) Portugal 1: Junta Nacional de investigagao Cientifica e Tecnologica (JNICT, contract No. PMCT/C/SAU/815.90) Portugal 2: Comissao de Fomento de investigaqao em Cuidados de Saude 111