AMERICAN JOURNAL OF INDUSTRIAL MEDICINE 58:437–443 (2015)
French Firefighter Mortality: Analysis Over a 30-year Period Amadeo Brice, PhD,1,2,3 Marchand Jean-Luc, PhD,4 Moisan Frédéric, PhD,4 Donnadieu Stéphane, MD,5 Coureau Gaëlle, MD, PhD,1,6,7 Mathoulin-Pélissier Simone, MD, PhD,1,2,3,8,9 Lembeye Christian, MD,10 Imbernon Ellen, MD, PhD,4 and Brochard Patrick, MD, PhD1,2,3,11
Objective To explore mortality of French professional male firefighters. Methods Standardized mortality ratios (SMR) were calculated for 10,829 professional male firefighters employed in 1979 and compared with the French male population between 1979–2008. Firefighters were identified from 89 French administrative departments (93% of population). Results One thousand six hundred forty two deaths were identified, representing significantly lower all-cause mortality than in the general population (SMR ¼ 0.81; 95% CI: 0.77–0.85). SMR increased with age and was not different from 1 for firefighters >70 years. No significant excess of mortality was observed for any specific cause, but a greater number of deaths than expected were found for various digestive neoplasms (rectum/anus, pancreas, buccal-pharynx, stomach, liver, and larynx). Conclusion We observed lower all and leading-cause mortality likely due to the healthy worker effect in this cohort, with diseases of the respiratory system considerably lower (SMR ¼ 0.57). Non-significant excesses for digestive neoplasms are notable, but should not be over-interpreted at this stage. Am. J. Ind. Med. 58:437–443, 2015. ß 2015 Wiley Periodicals, Inc.
KEY WORDS: death certificates; epidemiology; firefighter; France; mortality; neoplasm
INTRODUCTION 1
Universite´ de Bordeaux Segalen, Bordeaux, France Institut de Sante´ Publique d’Epide´miologie et de De´veloppement, Universite´ de Bordeaux Segalen, Bordeaux, France 3 INSERM U897^Epidemiology and Biostatistics, Bordeaux, France 4 De´partement sante´-travail, Institut de veille sanitaire, Saint-Maurice cedex, France 5 Direction Ge´ne´rale de la Se´curite´ Civile et de la Gestion des Crises, Paris, France 6 Registre ge´ne´ral des cancers, Bordeaux, France 7 Service d’information me´dicale, Centre hospitalier universitaire, Bordeaux, France 8 INSERM CIC-EC7, Bordeaux, France 9 Clinical Research and Clinical Epidemiology Unit, Institut Bergonie´, Regional Comprehensive Cancer Centre, Bordeaux, France 10 Ecole nationale supe´rieure des officiers de sapeurs-pompiers, Aix-en-Provence, France 11 Service de me´decine du travail et de pathologies professionnelles, Centre hospitalier universitaire, Bordeaux, France Correspondence to: Amadeo Brice, PhD, Universite´ Bordeaux Segalen, ISPED, Registre ge´ne´ral des cancers, 146 rue Le´o Saignat, 33076, Bordeaux, France. E-mail: [email protected] 2
Accepted 7 January 2015 DOI 10.1002/ajim.22434. Published online 23 February 2015 in Wiley Online Library (wileyonlinelibrary.com).
ß 2015 Wiley Periodicals, Inc.
Firefighting activities in France cover a large range of dangerous tasks, such as preventing and combating fires, assisting the population in transport or industrial accidents, natural disasters, or terrorist attacks, and environmental protection. These tasks expose French firefighters to many possible hazards [Europa Agency, 2011]. Several mortality studies have been conducted for firefighters in different countries, such as the United States [Musk et al., 1978; Rosenstock et al., 1990; Demers et al., 1992; Baris et al., 2001; Daniels et al., 2013], Canada [Bates, 1987; Guidotti, 1993; Aronson et al., 1994], Denmark [Hansen, 1990], Sweden [Tornling et al., 1994], Germany [Wagner et al., 2006] and Australia [Eliopulos et al., 1984]. Most of these studies showed a lower overall mortality compared to the general population and heterogeneous results with respect to other causes such as non-malignant cardio-respiratory diseases.
438
Amadeo et al.
Regarding malignant diseases, an increased mortality compared to the general population was observed for various sites [LeMasters et al., 2006]. In 2007, the WHO International Agency for Research on Cancer Monograph Working Group concluded that firefighters face occupational exposures that may include human carcinogens (list 2B), which consistently result in increased relative risks for testicular and prostate malignant neoplasms and nonHodgkin’s lymphoma [Straif et al., 2007]. In France, 249,300 men and women were worked as firefighters in 2010: 79% as volunteers, 16% as professionals and 5% as members of the military forces. Fatal accidents at work represent a mean of 18 deaths a year over the last decade [Direction de la sécurité civile, 2010]. While these fatal accident data are available, no health data are available at a national level. To our knowledge, only one local mortality study has been performed in France in this occupational group but it was restricted to military firefighters in Paris [Deschamps et al., 1995]. Given the lack of information about the impact of firefighting activities on health at the population level in France, we conducted a large-scale cohort study with all French professional male firefighters employed on January 1, 1979 and compared their overall and cause-specific mortality to that of the French national population.
MATERIALS AND METHODS Study Design The study population included all professional male firefighters employed on January 1, 1979 in France. This date was chosen in order to obtain a sufficient timelag between occupational exposure and disease occurrence such as malignant neoplasms or cardiorespiratory disease. The military firefighter units providing fire protection to Paris (Paris Fire Brigade-Army) and Marseille (Marseille Naval Fire Battalion-Navy) were not taken into account in this study due to organizational constraints. Volunteer firefighters were not included because no consolidated list of volunteers employed at this date was available. Moreover, volunteer firefighters usually hold “day” jobs which may pose separate occupational risks, and thus could confound the findings. Firefighters in France can be male or female. However, on January 1, 1979, there were only 11 female firefighters. For this reason, we only focused our study on male firefighters. This cohort, named the C.PRIM cohort (in reference to Charles Prim, a deceased doctor who was a pioneer in implementing health services for firefighters) was studied over a 30-year period from January 1, 1979 to December 31, 2008. The overall and cause-specific mortalities in
professional firefighters were compared with mortalities in the general French male population. The French National Commission on Informatics and Liberty (CNIL) whose mission is to ensure that data privacy law applied to the collection, storage and use of personal data approved the study protocol of the C.PRIM cohort.
Fire and Rescue Service Organization in France and Data Collection The implementation of the C.PRIM cohort required collecting national-level administrative data for all professional firefighters. However, in France no centralized data exist because the fire and rescue service organization is based on 96 administrative departmental structures that are independent of each other. These departmental structures are named “Service Départemental d’Incendie et de Secours” (SDIS) and are directed by a chief firefighter officer. Data regarding each professional firefighter were thus located within each SDIS. With respect to the fire and rescue service organization, a ministry circular was sent to each SDIS chief officer in January 2011, requiring each of them to declare a coordinator in their departmental structure for the constitution of the cohort. Overall, coordinator were named in 89 of 96 departments (93%). The coordinator was in charge of identifying professional firefighters employed on January 1, 1979 from professional staff records in his or her SDIS or in other institutions within the department. Registration (first and family names, place and date of birth) and basic career data (date of entry as firefighter and date of final activity as career firefighter) data were collected for each firefighter. Detailed data regarding firefighter activity were not available. The referents identified 11,577 eligible firefighters with an available entry date as firefighters. Vital status and causes of death were collected using an automatized procedure defined by law, after obtaining the required authorizations. Vital status of all firefighters on December 31, 2008 was provided by the national statistics institute (INSEE). The vital status was determined by linkages of five firefighter characteristics (first name, family name, sex, place and date of birth) with the National Identification Register of Private Individuals (RNIPP: Répertoire national d’identification des personnes Physiques). The main cause of death was sought for each deceased firefighter from the national database containing medical causes of death (INSERM-CépiDC: Institut National de la Santé et de la Recherche Médicale, centre d’épidémiologie sur les causes médicales de décès). This database compiles the medical death certificates completed by physicians and contains the medical causes of death
French Firefighter Mortality
coded using the International Classification of Diseases (ICD) of the World Health Organization [Eurostat. Metadata: European Shortlist for Causes of Death, 1998). The final database contained 10,829 firefighters with an identified vital status (94%).
439
cardiopathies (43%). Regarding external causes (14% overall), accidents and suicides were the main causes, representing 50% and 44% respectively.
SMRs for Overall and Leading Causes of Death
Statistical Analyses Standardized mortality ratios (SMRs) were used to evaluate the general and cause-specific mortality risks. SMRs were calculated by dividing the observed numbers of deaths to number of deaths expected, using the French male general population rate as references. Confidence intervals (95% CI) based on the exact Poisson limit for the observed number of deaths were calculated to assess the statistical significance [Liddell, 1984]. The French male general population reference rate was available by year and 5-year age-classes according to the European shortlist of 65 causes of death. All statistics analyses were performed using SAS (Version 9.1; SAS Institute Inc., Cary, NC). The number of person-years and SMR were calculated using a simple SAS program for exact calculations reported elsewhere [Marchand, 2010].
RESULTS Firefighter Characteristics Over the 30-year period, the 10,829 professional firefighters represented 308,089 person-years. Table I summarizes personal firefighter characteristics. On January 1, 1979, the mean age of all professional firefighters was 30 years (range: 17–64) and 83% of them were born after 1940. On December 31, 2008, 77% of all firefighters in the cohort had completed their career, for an average career length of 29 years.
Vital Status and Causes of Death Over the 30-year period, 1,642 deaths (15%) occurred. The cause of death was known for 1,615 of these individuals (99%). The main cause of death was malignant neoplasms which accounted for 45% of all deaths, followed by circulatory system diseases (19%) and external causes (14%). Of the malignant neoplasm deaths, lung and bronchus malignant neoplasms was the most common site, accounting for 25% of all malignant neoplasms, followed by buccalpharynx (9%), liver (6%), pancreas (6%), and lymphopoietic malignant neoplasms (6%). The majority of deaths from circulatory system diseases (19% overall) were ischemic
Table II shows SMRs for the overall firefighter population according to firefighter characteristics. Between 1979 and 2008, a lower number of deaths (1,642) than expected was found in the overall firefighter population compared to general population estimates (2,036) (SMR ¼ 0.81; 95% CI: 0.77–0.85) representing a significantly lower mortality. SMRs progressively increased with age and were close to 1 from the age of 70 years. Table III summarizes SMRs for the leading causes of death. No SMRs were significantly higher than 1. Significantly lower mortality was observed for ten of fifteen leading causes of death. The lowest SMRs were found for infectious and parasitic diseases (SMR ¼ 0.30; 95% CI: 0.16–0.50) and respiratory diseases (SMR ¼ 0.54; 95% CI: 0.39–0.73). However, malignant neoplasm mortality (SMR ¼ 0.95; 95% CI: 0.88–1.02) and mortality due to genitourinary diseases (SMR ¼ 0.94; 95% CI: 0.50–1.61) were not different from that of the French male general population. The site-specific malignant neoplasm SMRs for professional male firefighters are presented in Table IV. Compared to the French male population, professional male firefighters exhibited significantly lower mortality from malignant lung and bronchus neoplasms (SMR ¼ 0.86; 95% CI: 0.74–0.99)
TABLE I. Characteristics of French Male Professional Firefighters Employed on January1, 1979 ^ the Charles Prim (C.PRIM) Cohort Total Characteristics Age on January1,1979
French Firefighter Mortality: Analysis Over a 30-year Period Amadeo Brice, PhD,1,2,3 Marchand Jean-Luc, PhD,4 Moisan Frédéric, PhD,4 Donnadieu Stéphane, MD,5 Coureau Gaëlle, MD, PhD,1,6,7 Mathoulin-Pélissier Simone, MD, PhD,1,2,3,8,9 Lembeye Christian, MD,10 Imbernon Ellen, MD, PhD,4 and Brochard Patrick, MD, PhD1,2,3,11
Objective To explore mortality of French professional male firefighters. Methods Standardized mortality ratios (SMR) were calculated for 10,829 professional male firefighters employed in 1979 and compared with the French male population between 1979–2008. Firefighters were identified from 89 French administrative departments (93% of population). Results One thousand six hundred forty two deaths were identified, representing significantly lower all-cause mortality than in the general population (SMR ¼ 0.81; 95% CI: 0.77–0.85). SMR increased with age and was not different from 1 for firefighters >70 years. No significant excess of mortality was observed for any specific cause, but a greater number of deaths than expected were found for various digestive neoplasms (rectum/anus, pancreas, buccal-pharynx, stomach, liver, and larynx). Conclusion We observed lower all and leading-cause mortality likely due to the healthy worker effect in this cohort, with diseases of the respiratory system considerably lower (SMR ¼ 0.57). Non-significant excesses for digestive neoplasms are notable, but should not be over-interpreted at this stage. Am. J. Ind. Med. 58:437–443, 2015. ß 2015 Wiley Periodicals, Inc.
KEY WORDS: death certificates; epidemiology; firefighter; France; mortality; neoplasm
INTRODUCTION 1
Universite´ de Bordeaux Segalen, Bordeaux, France Institut de Sante´ Publique d’Epide´miologie et de De´veloppement, Universite´ de Bordeaux Segalen, Bordeaux, France 3 INSERM U897^Epidemiology and Biostatistics, Bordeaux, France 4 De´partement sante´-travail, Institut de veille sanitaire, Saint-Maurice cedex, France 5 Direction Ge´ne´rale de la Se´curite´ Civile et de la Gestion des Crises, Paris, France 6 Registre ge´ne´ral des cancers, Bordeaux, France 7 Service d’information me´dicale, Centre hospitalier universitaire, Bordeaux, France 8 INSERM CIC-EC7, Bordeaux, France 9 Clinical Research and Clinical Epidemiology Unit, Institut Bergonie´, Regional Comprehensive Cancer Centre, Bordeaux, France 10 Ecole nationale supe´rieure des officiers de sapeurs-pompiers, Aix-en-Provence, France 11 Service de me´decine du travail et de pathologies professionnelles, Centre hospitalier universitaire, Bordeaux, France Correspondence to: Amadeo Brice, PhD, Universite´ Bordeaux Segalen, ISPED, Registre ge´ne´ral des cancers, 146 rue Le´o Saignat, 33076, Bordeaux, France. E-mail: [email protected] 2
Accepted 7 January 2015 DOI 10.1002/ajim.22434. Published online 23 February 2015 in Wiley Online Library (wileyonlinelibrary.com).
ß 2015 Wiley Periodicals, Inc.
Firefighting activities in France cover a large range of dangerous tasks, such as preventing and combating fires, assisting the population in transport or industrial accidents, natural disasters, or terrorist attacks, and environmental protection. These tasks expose French firefighters to many possible hazards [Europa Agency, 2011]. Several mortality studies have been conducted for firefighters in different countries, such as the United States [Musk et al., 1978; Rosenstock et al., 1990; Demers et al., 1992; Baris et al., 2001; Daniels et al., 2013], Canada [Bates, 1987; Guidotti, 1993; Aronson et al., 1994], Denmark [Hansen, 1990], Sweden [Tornling et al., 1994], Germany [Wagner et al., 2006] and Australia [Eliopulos et al., 1984]. Most of these studies showed a lower overall mortality compared to the general population and heterogeneous results with respect to other causes such as non-malignant cardio-respiratory diseases.
438
Amadeo et al.
Regarding malignant diseases, an increased mortality compared to the general population was observed for various sites [LeMasters et al., 2006]. In 2007, the WHO International Agency for Research on Cancer Monograph Working Group concluded that firefighters face occupational exposures that may include human carcinogens (list 2B), which consistently result in increased relative risks for testicular and prostate malignant neoplasms and nonHodgkin’s lymphoma [Straif et al., 2007]. In France, 249,300 men and women were worked as firefighters in 2010: 79% as volunteers, 16% as professionals and 5% as members of the military forces. Fatal accidents at work represent a mean of 18 deaths a year over the last decade [Direction de la sécurité civile, 2010]. While these fatal accident data are available, no health data are available at a national level. To our knowledge, only one local mortality study has been performed in France in this occupational group but it was restricted to military firefighters in Paris [Deschamps et al., 1995]. Given the lack of information about the impact of firefighting activities on health at the population level in France, we conducted a large-scale cohort study with all French professional male firefighters employed on January 1, 1979 and compared their overall and cause-specific mortality to that of the French national population.
MATERIALS AND METHODS Study Design The study population included all professional male firefighters employed on January 1, 1979 in France. This date was chosen in order to obtain a sufficient timelag between occupational exposure and disease occurrence such as malignant neoplasms or cardiorespiratory disease. The military firefighter units providing fire protection to Paris (Paris Fire Brigade-Army) and Marseille (Marseille Naval Fire Battalion-Navy) were not taken into account in this study due to organizational constraints. Volunteer firefighters were not included because no consolidated list of volunteers employed at this date was available. Moreover, volunteer firefighters usually hold “day” jobs which may pose separate occupational risks, and thus could confound the findings. Firefighters in France can be male or female. However, on January 1, 1979, there were only 11 female firefighters. For this reason, we only focused our study on male firefighters. This cohort, named the C.PRIM cohort (in reference to Charles Prim, a deceased doctor who was a pioneer in implementing health services for firefighters) was studied over a 30-year period from January 1, 1979 to December 31, 2008. The overall and cause-specific mortalities in
professional firefighters were compared with mortalities in the general French male population. The French National Commission on Informatics and Liberty (CNIL) whose mission is to ensure that data privacy law applied to the collection, storage and use of personal data approved the study protocol of the C.PRIM cohort.
Fire and Rescue Service Organization in France and Data Collection The implementation of the C.PRIM cohort required collecting national-level administrative data for all professional firefighters. However, in France no centralized data exist because the fire and rescue service organization is based on 96 administrative departmental structures that are independent of each other. These departmental structures are named “Service Départemental d’Incendie et de Secours” (SDIS) and are directed by a chief firefighter officer. Data regarding each professional firefighter were thus located within each SDIS. With respect to the fire and rescue service organization, a ministry circular was sent to each SDIS chief officer in January 2011, requiring each of them to declare a coordinator in their departmental structure for the constitution of the cohort. Overall, coordinator were named in 89 of 96 departments (93%). The coordinator was in charge of identifying professional firefighters employed on January 1, 1979 from professional staff records in his or her SDIS or in other institutions within the department. Registration (first and family names, place and date of birth) and basic career data (date of entry as firefighter and date of final activity as career firefighter) data were collected for each firefighter. Detailed data regarding firefighter activity were not available. The referents identified 11,577 eligible firefighters with an available entry date as firefighters. Vital status and causes of death were collected using an automatized procedure defined by law, after obtaining the required authorizations. Vital status of all firefighters on December 31, 2008 was provided by the national statistics institute (INSEE). The vital status was determined by linkages of five firefighter characteristics (first name, family name, sex, place and date of birth) with the National Identification Register of Private Individuals (RNIPP: Répertoire national d’identification des personnes Physiques). The main cause of death was sought for each deceased firefighter from the national database containing medical causes of death (INSERM-CépiDC: Institut National de la Santé et de la Recherche Médicale, centre d’épidémiologie sur les causes médicales de décès). This database compiles the medical death certificates completed by physicians and contains the medical causes of death
French Firefighter Mortality
coded using the International Classification of Diseases (ICD) of the World Health Organization [Eurostat. Metadata: European Shortlist for Causes of Death, 1998). The final database contained 10,829 firefighters with an identified vital status (94%).
439
cardiopathies (43%). Regarding external causes (14% overall), accidents and suicides were the main causes, representing 50% and 44% respectively.
SMRs for Overall and Leading Causes of Death
Statistical Analyses Standardized mortality ratios (SMRs) were used to evaluate the general and cause-specific mortality risks. SMRs were calculated by dividing the observed numbers of deaths to number of deaths expected, using the French male general population rate as references. Confidence intervals (95% CI) based on the exact Poisson limit for the observed number of deaths were calculated to assess the statistical significance [Liddell, 1984]. The French male general population reference rate was available by year and 5-year age-classes according to the European shortlist of 65 causes of death. All statistics analyses were performed using SAS (Version 9.1; SAS Institute Inc., Cary, NC). The number of person-years and SMR were calculated using a simple SAS program for exact calculations reported elsewhere [Marchand, 2010].
RESULTS Firefighter Characteristics Over the 30-year period, the 10,829 professional firefighters represented 308,089 person-years. Table I summarizes personal firefighter characteristics. On January 1, 1979, the mean age of all professional firefighters was 30 years (range: 17–64) and 83% of them were born after 1940. On December 31, 2008, 77% of all firefighters in the cohort had completed their career, for an average career length of 29 years.
Vital Status and Causes of Death Over the 30-year period, 1,642 deaths (15%) occurred. The cause of death was known for 1,615 of these individuals (99%). The main cause of death was malignant neoplasms which accounted for 45% of all deaths, followed by circulatory system diseases (19%) and external causes (14%). Of the malignant neoplasm deaths, lung and bronchus malignant neoplasms was the most common site, accounting for 25% of all malignant neoplasms, followed by buccalpharynx (9%), liver (6%), pancreas (6%), and lymphopoietic malignant neoplasms (6%). The majority of deaths from circulatory system diseases (19% overall) were ischemic
Table II shows SMRs for the overall firefighter population according to firefighter characteristics. Between 1979 and 2008, a lower number of deaths (1,642) than expected was found in the overall firefighter population compared to general population estimates (2,036) (SMR ¼ 0.81; 95% CI: 0.77–0.85) representing a significantly lower mortality. SMRs progressively increased with age and were close to 1 from the age of 70 years. Table III summarizes SMRs for the leading causes of death. No SMRs were significantly higher than 1. Significantly lower mortality was observed for ten of fifteen leading causes of death. The lowest SMRs were found for infectious and parasitic diseases (SMR ¼ 0.30; 95% CI: 0.16–0.50) and respiratory diseases (SMR ¼ 0.54; 95% CI: 0.39–0.73). However, malignant neoplasm mortality (SMR ¼ 0.95; 95% CI: 0.88–1.02) and mortality due to genitourinary diseases (SMR ¼ 0.94; 95% CI: 0.50–1.61) were not different from that of the French male general population. The site-specific malignant neoplasm SMRs for professional male firefighters are presented in Table IV. Compared to the French male population, professional male firefighters exhibited significantly lower mortality from malignant lung and bronchus neoplasms (SMR ¼ 0.86; 95% CI: 0.74–0.99)
TABLE I. Characteristics of French Male Professional Firefighters Employed on January1, 1979 ^ the Charles Prim (C.PRIM) Cohort Total Characteristics Age on January1,1979
