Use of multiple cause of death data in cancer mortality analyses

BACKGROUND: In a cancer mortality study, the decision of whether to define a study outcome via underlying cause of death (UCD) or via multiple cause of death (MCD) information may impact relative risk (RR) estimates and associated confidence intervals. METHODS: Simple equations are presented that relate RR estimates obtained in a cancer incidence study to the RR estimates obtained in mortality studies using UCD and MCD information. Data from the Surveillance, Epidemiology and End Results program were used to obtain information about the detection and confirmation rates of cancer diagnoses made via UCD. Data from US cause of death data tapes were used to obtain information on the ratio of UCD to MCD listings for cancer outcomes. Numerical examples illustrate the use of these equations. RESULTS: In our examples, the RRs obtained via analyses of MCD were close to those obtained via analyses of UCD (but of greater precision), even when assuming that the confirmation rate of cancer diagnoses made via MCD listing was substantially lower than that of diagnoses made via UCD. CONCLUSIONS: These finding are supportive of the use of MCD information in cancer mortality studies.     

Using multiple cause of death coding in occupational mortality studies

Conventional occupational mortality analysis, using underlying cause of death coding, underestimates the contribution of those chronic diseases which are mentioned on the death certificate but which usually do not appear as underlying cause of death. Proportionate occupational mortality analysis, using all the mentioned causes on the Washington State male death records 1968-1984, identified an excess of rheumatoid arthritis in farmers, and asbestosis in plumbers, pipefitters, and steamfitters.     

Mortality from bladder cancer in dyestuff workers exposed to aromatic amines: A 73-year follow-up

Objective:To update the analysis of mortality of a cohort of dyestuff workers, in northern Italy, heavily exposed to carcinogenic aromatic amines.Methods:We updated to 2018 overall and cause-specific mortality in a cohort of 590 male workers heavily exposed to carcinogenic aromatic amines in a dyestuff factory from 1922 to 1972. Workers were censored at age 85. Expected cases for the period 1946-2018 were computed using Piedmont mortality rates and standardized mortality ratios (SMR) were computed.Results:Between 1946 and 2018, 470 deaths were reported. The overall SMR from all causes was 1.59 (95% confidence interval [CI] 1.45-1.74) and the SMR from all cancers was 2.05 (95% CI = 1.77-2.37); compared to a previous report, there were 4 additional deaths from bladder cancer, for a total of 60 deaths compared with 4.0 expected (SMR 14.86, 95% CI 11.34-19.12). The SMR for bladder cancer increased with younger age at first exposure and longer duration of exposure, while it decreased with time since last exposure, albeit it was still 3.5, 30, or more years since last exposure. An increased risk was observed among workers exposed to fuchsine or ortho-toluidine (SMR=16.3; 95% CI = 6.0-35.5).Conclusions:This 73-year follow-up confirms the results from previous analyses, with increased overall mortality, and increased mortality from all cancers and especially for bladder cancer. The excess risk of bladder cancer persisted several decades after stopping exposure.     

Cancer mortality among a cohort of chromium pigment workers

A study of mortality among 1,879 male workers employed in a New Jersey chromium pigment factory was carried out, with follow-up from 1940 to 1982. Vital status of 1,737 (92%) of the eligible cohort members was determined. For all malignant neoplasms, 101 deaths were observed while 108.8 were expected, SMR = 93 (standardized mortality ratio; n.s.). For the entire study group, no significant excess was observed for respiratory cancer or cancer at other sites. However, the total number of years of employment in the factory and the total number of years of exposure to chromate dusts were both statistically significantly (p less than .05, for trend) associated with an increased risk for lung cancer. The excess risk for lung cancer associated with duration of exposure to chromate dusts was, however, only clearly apparent for subjects followed for 30 years or more after initial employment. For this group, the SMRs were 81, 139, 201, and 321 for the subjects with 0 years, less than 1 year, 1-9 years, and 10+ years of exposure to chromate dusts (p less than .01, for trend), respectively. The risk for digestive cancer was only weakly associated with exposure to chromate dusts.     

Cancer mortality in a cohort of male German iron foundry workers

BACKGROUND: Observations of an increased incidence of cancers of the upper aero-digestive tract (pharynx, esophagus, larynx, lung) among workers of local German foundries gave rise to concern about a potentially elevated occupational risk of those cancer sites. The purpose of the study was to examine whether occupational exposure in iron foundries increases the risk of cancer. METHODS: A historical cohort study of 17,708 male German production workers in 37 iron foundries who were first employed in 1950-1985 with a minimum employment period of 1 year was initiated. Employment and occupational histories were collected. Mortality was compared with that of the German general population during 1950-1993 using a new method for computing the SMR when not all causes of death are available (called SMR*). RESULTS: Mortality from all causes was elevated to SMR = 115.4 (95% confidence interval (CI) = 111.9-119.1), as was for total cancer (SMR* = 123.8, CI = 102.1-152.6), especially cancers of the lung (SMR* = 163.9, CI = 123.9-223.0) and liver (SMR* = 322.5, CI = 149.5-844.8), and diseases of the respiratory system (SMR* = 147.6, CI = 100.4-221.5). Non-significant elevations of mortality were also found for cancers of the mouth and pharynx (SMR* = 153.5, CI = 82.3-359.8) and larynx (SMR* = 173.1, CI = 85.5-550.5). Mortality from various causes of death was higher among workers with shorter exposure periods than among long-term employees. The elevated mortality persisted for years and decades after termination of employment. CONCLUSIONS: The results provide further evidence for an increased risk of lung cancer and possibly other cancers of the upper aero-digestive tract among foundry workers. Special attention should be paid to the strongly increased mortality from liver cancer and the mortality pattern among employees having terminated work.     

A cohort mortality study of construction workers

This report presents a mortality study among the 17,344 members of the Construction Workers' Health Insurance Society of Mie Prefecture in Japan. The study period was between 1973 and 1993. During this period, 480 members died. Age-specific mortality rates of Mie Prefecture were used as comparison standards. Significantly elevated standardized mortality ratio (SMR) and proportionate mortality ratio (PMR) were observed for “accidents and adverse effects.” In addition, the PMRs of all cancers and “cancers of trachea, bronchus and lung” were also significantly elevated. The job classifications were reorganized into three groups, according to the frequency of asbestos exposure the workers experienced on the construction sites. The asbestos exposure was based on job classifications among 7,411 workers who had completed a self-administered survey questionnaire. In the frequent-exposure group, the PMR was significantly elevated for all cancers. In the medium-exposure group, the SMRs were significantly elevated for all cancers and “cancer of trachea, bronchus and lung.” The PMR was significantly elevated for “cancer of trachea, bronchus and lung.” In the less-exposure group, the PMR was significantly elevated for “accidents and adverse effects.” This study provided support for the hypothesis that working in the construction industry might be associated with high risks for asbestos-associated cancers and accidental deaths. Am. J. Ind. Med. 32:35-41, 1997. © 1997 Wiley-Liss, Inc.     

Nonrespiratory mortality and cancer incidence in a cohort of Canadian nickel workers

Mortality and cancer incidence were examined for an updated cohort of nonsinter nickel workers in Sudbury and Port Colborne, Ontario, Canada. Abstract results are provided for those with ≥ 15 years since first exposure. For circulatory disease mortality, significant elevations were observed overall in many Sudbury work areas and in Port Colborne staff. Underground miners, with first exposure before 1960, displayed significant elevations for pneumoconiosis, as well as silicosis and anthrasilicosis, likely due to crystalline silica. Significant elevations in colorectal cancer incidence were observed in Sudbury underground mining, mining maintenance, and maintenance work areas. Given a case-control study is not practical, the next cohort update should include more detailed occupational exposure assessment, including dust exposure, diesel engine emissions, solvents, various metals, silica, and sulphur dioxide.     

The Drake Health Registry Study: cause-specific mortality experience of workers potentially exposed to beta-naphthylamine

OBJECTIVE: To examine the cause-specific mortality experience of an occupational cohort with probable past exposure to beta-naphythylamine (BNA). METHODS: Subjects were 374 male and 26 female workers employed at a Pennsylvania chemical plant that produced or used beta-naphthylamine (BNA) between 1940 and 1981. Vital status through 1998 was determined for 97.5% of the cohort and cause of death for 100% of 79 deaths. Limited industrial hygiene data and reports from former employees were used to categorize workers as high, medium, or low risk for BNA exposure. Statistical analyses included US and local county-based standardized mortality ratios (SMRs). RESULTS: We observed statistically significantly elevated county rate-based SMRs for all causes combined (SMR = 1.98, 95% confidence interval (CI) = 1.56-2.49), all malignant neoplasms combined (28 deaths, SMR = 3.08, 95% CI = 2.05-4.46), respiratory system cancer (12 deaths, SMR = 3.91, 95% CI = 2.02-6.83), and bladder cancer (four deaths, SMR = 16.83, 95% CI = 4.59-43.1). Three bladder cancer cases were classified as high risk (SMR = 26.79, 95% CI = 5.53-78.29). Mortality risks were also elevated for most other malignant and non-malignant cause of death categories examined. CONCLUSIONS: Bladder cancer risk remains highly elevated among Drake/Kilsdonk workers and appears to be causally related to past BNA exposure. While lifestyle and behavioral risk factors may explain some of the mortality excesses for non-urological cancers, the possibility remains that BNA exposure may have also played a role in these and other observed cancer excesses.     

Estimated effects of solvents and mineral oils on cancer incidence and mortality in a cohort of aerospace workers

BACKGROUND: A retrospective cohort study of workers employed at a California aerospace company between 1950 and 1993 was conducted; it examined cancer mortality from exposures to the rocket fuel hydrazine. METHODS: In this study, we employed a job exposure matrix (JEM) to assess exposures to other known or suspected carcinogens-including trichloroethylene (TCE), polycyclic aromatic hydrocarbons (PAHs), mineral oils, and benzene-on cancer mortality (1960-2001) and incidence (1988-2000) in 6,107 male workers. We derived rate- (hazard-) ratios estimates from Cox proportional hazard models with time-dependent exposures. RESULTS: High levels of TCE exposure were positively associated with cancer incidence of the bladder (rate ratio (RR): 1.98, 95% confidence interval (CI) 0.93-4.22) and kidney (4.90; 1.23-19.6). High levels of exposure to mineral oils increased mortality and incidence of lung cancer (1.56; 1.02-2.39 and 1.99; 1.03-3.85), and incidence of melanoma (3.32; 1.20-9.24). Mineral oil exposures also contributed to incidence and mortality of esophageal and stomach cancers and of non-Hodgkin's lymphoma and leukemia when adjusting for other chemical exposures. Lagging exposure measures by 20 years changed effect estimates only minimally. No associations were observed for benzene or PAH exposures in this cohort. CONCLUSIONS: Our findings suggest that these aerospace workers who were highly exposed to mineral oils experienced an increased risk of developing and/or dying from cancers of the lung, melanoma, and possibly from cancers of the esophagus and stomach and non-Hodgkin's lymphoma and leukemia. These results and the increases we observed for TCE and kidney cancers are consistent with findings of previous studies.     

Cancer incidence and mortality among workers exposed to acrylonitrile

A cohort of 1,083 male employees who had potential for exposure to acrylonitrile between 1944 and 1970 at a Du Pont textile fibers plant were followed through 1981 for mortality and through 1983 for cancer incidence. In total, the 21 cancer deaths were fewer than expected based on either Du Pont or U.S. rates. No significant excesses were seen by primary site. In all, 37 cancer cases occurred as compared with 36.5 expected based on company rates. Five lung cancer cases were observed and 6.9 expected. There were 5 prostate cancer cases as compared with 1.9 expected. Of these, 4 occurred among wage employees during the 1975-1983 period, compared to 0.9 expected. This excess was statistically significant.     

Cancer incidence and mortality in workers employed at a transformer manufacturing plant: update to a cohort study

BACKGROUND: This study is an extension of a previously published analysis of cancer mortality in a transformer manufacturing plant where there had been extensive use of mineral oil transformer fluid. The objectives of the present study were to update the mortality analysis and include deaths for the past 6 years as well as to do an analysis of cancer incidence of the cohort. METHODS: A cohort of 2,222 males working at a transformer manufacturing plant between 1946 and 1975 was constructed. Using a classical historical cohort study design, cancer incidence and mortality were determined through record linkage with Canadian provincial and national registries. The rates of cancer incidence and mortality experienced by this cohort were compared to that of the Canadian male population. RESULTS: A statistically significant increased risk of developing and dying of pancreatic cancer was found but not an increase in overall cancer mortality. This was consistent with the previous report from this group. Interestingly, the cohort demonstrated a statistically significant risk of overall cancer incidence and specific increased incidence of gallbladder cancer. CONCLUSIONS: This study contributes further evidence to the growing body of literature indicating the carcinogenic properties of mineral oils used in occupational settings, in particular those used prior to 1970s.     

2000～2004年西安市孕产妇死亡率及原因分析

目的通过孕产妇死亡资料的分析,为进一步降低孕产妇死亡率提供科学的依据。方法采用回顾性研究的方法,对2000～2004年来西安市孕产妇死亡情况进行分析。结果5年来西安市孕产妇死亡率为30.92/10万～50.51/10万。产科出血居死因顺位第一位,从2002年起,妊娠期高血压疾病所占死亡比例开始升高,2003年和2004年分别居死因第三位和第二位。结论西安市孕产妇死亡率与39/10万的目标仍有很大差距,要进一步降低全市孕产妇死亡率,必须加强孕产妇的保健管理。     

Injury mortality in a cohort of mining,smelting, and refining workers in Ontario

Injury mortality was followed up from 1950 to 2000 in a cohort of 56,576 nickel workers. Injury fatalities were elevated throughout the cohort of never sinter plant workers (SMR = 134, 95% CI [129, 140]). Elevations were also observed in injury mortality subcategories of road, rail, and air (SMR = 137, 95% CI [127, 147]); boating and swimming (SMR = 150, 95% CI [128, 176]); suicide and possible suicide (SMR = 124, 95% CI [114, 135]); and possibly job-related accidents (SMR = 160, 95% CI [145, 175]). The results were largely attributed to underground miners, with 61.4% of all injury mortality (SMR = 162; 95% CI [153, 171]). Occupational etiology could not be ascertained; however, compiled workplace injury fatalities are presented separately. Recommendations include delivery of injury prevention and wellness programs in partnership with the local health unit and other stakeholders.     

Cancer mortality among workers exposed to formaldehyde

Proportionate mortality among workers exposed to formaldehyde was analyzed among employees of a large chemical plant in Western Massachusetts. Twenty-four such decedents, all males, were identified through union records, reports of former coworkers, and a systematic review of obituaries in local newspapers. Work histories were obtained from seniority lists. Race-age-sex-adjusted proportionate mortality ratios (PMRs) were significantly elevated for cancer of the colon based on United States. county, and county cancer mortality proportions (PMR = 702, 424, 333, p ≤ 0.05). as were PMRs for the category buccal and pharyngeal cancer (PMR = 870, 952, 833. p < 0.05). This study provides evidence of formaldehyde's carcinogenicity. These findings are at variance with a previous report of the mortality experience of workers at the same plant from an earlier period.     

西安市2000～2008年孕产妇死亡趋势与原因探析

目的 探讨孕产妇死亡的变化趋势、影响因素、根本原因及其风险因素,以改善应对措施,确保母婴安全.方法 对西安市2000～2008年常住人口和流动人口中死亡的孕产妇资料,使用Excel数据库进行资料录入,利用SPSS 13.0软件包进行统计学分析.结果 西安市常住人口中孕产妇死亡率有逐年下降的趋势,平均为36.06/10万,2008年在2000年的基础上显著下降了57.28%(χ2=5.205,P=0.030<0.05);流动人口中的孕产妇死亡率平均为213.45/10万,流动人口中的孕产妇死亡率显著高于常住人口中的孕产妇死亡率(χ2=60.814,P=0.000<0.05);孕产妇死亡的前5位死因依次是产后出血、羊水栓塞、妊娠期高血压疾病、妊娠合并症、胎盘早剥;孕产妇产后出血的死亡率有逐年下降的趋势;死亡孕产妇中高危年龄占到17.24%,88.28%居住在农村地区;孕期仅有37.24%产前检查达到5次;死亡孕产妇的孕期系统保健管理率(χ2=410.648,P=0.000<0.05 )与住院分娩率(χ2=56.485,P=0.000<0.05)显著低于全市;孕产妇死亡率与孕期系统保健管理率(r =-0.719,P<0.05)、住院分娩率(r=-0.799,P<0.01)呈显著负相关;评审结果显示死亡孕产妇中有85.90%是可以避免或创造条件可以避免的死亡.结论 西安市常住人口中孕产妇死亡率已经达到<西安市妇女发展纲要(2001～2010年)>目标,但85.9%是可以避免的死亡.应不断提高孕产妇的早孕检查率、系统保健管理率、住院分娩率,加强高危孕产妇的监管,将可避免的孕产妇死亡降到最低水平.     

Cancer mortality in German carbon black workers 1976-98

Background

Few studies have investigated cancer risks in carbon black workers and the findings were inconclusive.

Methods

The current study explores the mortality of a cohort of 1535 male German blue‐collar workers employed at a carbon black manufacturing plant for at least one year between 1960 and 1998. Vital status and causes of death were assessed for the period 1976–98. Occupational histories and information on smoking were abstracted from company records. Standardised mortality ratios (SMR) and Poisson regression models were calculated.

Results

The SMRs for all cause mortality (observed deaths (obs) 332, SMR 120, 95% CI 108 to 134), and mortality from lung cancer (obs 50, SMR 218, 95% CI 161 to 287) were increased using national rates as reference. Comparisons to regional rates from the federal state gave SMRs of 120 (95% CI 107 to 133) and 183 (95% CI 136 to 241), respectively. However, there was no apparent dose response relationship between lung cancer mortality and several indicators of occupational exposure, including years of employment and carbon black exposure.

Conclusions

The mortality from lung cancer among German carbon black workers was increased. The high lung cancer SMR can not fully be explained by selection, smoking, or other occupational risk factors, but the results also provide little evidence for an effect of carbon black exposure.     

Cancer mortality in a surveillance cohort of German males formerly exposed to asbestos

The objective of this analysis was the estimation of the cancer risks of asbestos and asbestosis in a surveillance cohort of high-exposed German workers. A group of 576 asbestos workers was selected for high-resolution computer tomography of the chest in 1993-1997. A mortality follow-up was conducted through 2007. Standardised mortality ratios (SMRs) were calculated and Poisson regression was performed to assess mesothelioma risks. A high risk was observed for pleural mesothelioma (SMR 28.10, 95% CI 15.73-46.36) that decreased after cessation of exposure (RR 0.1; 95% CI 0.0–0.6 for ≥30 vs. <30 years after last exposure). Asbestosis was a significant risk factor for mesothelioma (RR 6.0, 95% CI 2.4-14.7). Mesothelioma mortality was still in excess in former asbestos workers although decreasing after cessation of exposure. Fibrosis was associated with subsequent malignancy.