US Death Certificates Research Articles

Systemic autoimmune disease mortality and occupational exposures

To generate hypotheses regarding occupational exposures that may cause systemic autoimmune diseases. Based on examination of US death certificates, we identified deaths in 26 states for which a cause was listed as rheumatoid arthritis (RA) (n = 36,178), systemic lupus erythematosus (SLE) (n = 7,241), systemic sclerosis (n = 5,642), or other systemic autoimmune disease (n = 4,270). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to estimate associations between occupation and death from any systemic autoimmune disease, and from RA, SLE, and systemic sclerosis, specifically. Additionally, we estimated risks associated with occupational exposures, which were assigned using job-exposure matrices. A broad array of occupations was associated with death from systemic autoimmune diseases, including several of a priori interest. Farming occupation was associated with death from any systemic autoimmune disease (OR 1.3 [95% CI 1.2-1.4]), and increased risk was also seen with occupational exposure to animals and pesticides. Several industrial occupations were associated with death from any systemic autoimmune disease, including mining machine operators (OR 1.3 [95% CI 1.1-1.5]), miscellaneous textile machine operators (OR 1.2 [95% CI 1.0-1.4]), and hand painting, coating, and decorating occupations (OR 1.8 [95% CI 1.0-2.9]). These occupations were also significantly associated with death from the specific autoimmune diseases examined. Certain occupations entailing exposure to the public, such as teachers, were associated with systemic autoimmune disease-related death, whereas others, such as waiters and waitresses, were not. Our results suggest that death from systemic autoimmune diseases may be associated with occupational exposures encountered in farming and industry. The hypotheses generated in this study provide leads for future research on determinants of these diseases.

Bleeding Complications With Warfarin Use

Warfarin sodium is widely used and causes bleeding; a review might suggest the need for regulatory action by the US Food and Drug Administration (FDA). We accessed warfarin prescriptions from the National Prescription Audit Plus database of IMS Health (Plymouth Meeting, Pennsylvania), adverse event reports submitted to the FDA, deaths due to therapeutic use of anticoagulants from vital statistics data, and warfarin bleeding complications from national hospital emergency department data. The number of dispensed outpatient prescriptions for warfarin increased 45%, from 21 million in 1998 to nearly 31 million in 2004. The FDA's Adverse Event Reporting System indicated that warfarin is among the top 10 drugs with the largest number of serious adverse event reports submitted during the 1990 and 2000 decades. From US death certificates, anticoagulants ranked first in 2003 and 2004 in the number of total mentions of deaths for drugs causing "adverse effects in therapeutic use." Data from hospital emergency departments for 1999 through 2003 indicated that warfarin was associated with about 29 000 visits for bleeding complications per year, and it was among the drugs with the most visits. These data are consistent with literature reports of major bleeding frequencies for warfarin as high as 10% to 16%. Use of warfarin has increased, and bleeding from warfarin use is a prevalent reaction and an important cause of mortality. Consequently, a "black box" warning about warfarin's bleeding risk was added to the US product labeling in 2006. Physicians and nurses should tell patients to immediately report signs and symptoms of bleeding. A Medication Guide, which is required to be provided with each prescription, reinforces this message.

Amyotrophic Lateral Sclerosis Mortality in 1.9 Million US Cancer Survivors

Background: Large cancer registries offer the opportunity to explore and generate hypotheses about the pathogenesis of cancer and other diseases, including neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). Methods: Using data from nine population-based cancer registries of the Surveillance, Epidemiology, and End Results (SEER) Program of the US National Cancer Institute (NCI) and death certificates, we followed 1.9 million cancer survivors who were diagnosed between 1973 and 2000 and who survived at least 1 year, through the year 2000. The outcome of interest was the standardized mortality ratio (SMR) of observed to expected ALS deaths among cancer survivors. To assess the validity of the study design, we also examined associations with Parkinson’s disease mortality, which we expected to be inversely associated with smoking-related cancers. Results: There was no significantly increased risk or deficit of ALS mortality for all cancer sites combined (SMR = 1.0). Parkinson’s disease mortality was, as expected, significantly and inversely associated with smoking-related cancers. Both ALS and Parkinson’s disease mortality were significantly elevated following melanoma (SMR = 1.6; 95% CI = 1.1–2.2; SMR = 1.5; 1.2–1.8, respectively). Contrary to previous hypotheses, ALS was unrelated to lymphomas or lymphoproliferative malignancies and was not associated with smoking-related cancers. Conclusions: In this exploratory study, we observed a modest, significant association between melanoma and both ALS and Parkinson’s disease mortality. It would be useful to explore these findings in other large national databases that are able to link cancer and ALS and Parkinson’s disease.

Estimating the total number of newly-recognized silicosis cases in the United States.

The US employer-based surveillance system for documenting occupational injuries and illnesses undercounts chronic diseases. We suggest a method to estimate the number of individuals who are newly-recognized with silicosis each year in the United States. Data from US death certificates, the Michigan state-based surveillance system, and capture-recapture analysis were used to calculate national estimates of silicosis. From 1987 to 1996, 2,787 deaths occurred in the United States where silicosis was mentioned on the death certificates. During the same period, in Michigan 77% of death certificates with a mention of silicosis were confirmed as silicosis-related deaths and the ratio of the number of living to deceased confirmed silicosis cases was 6.44. The proportion of confirmed silicosis deaths, the ratio of the living to deceased silicosis cases and capture-recapture analysis from the Michigan surveillance system, were used to estimate that there were 3,600-7,300 cases per year of silicosis in the United States from 1987 to 1996. Our estimate of the annual number of newly-recognized silicosis cases is significantly larger than the estimate from the employer-based reporting system used for counting occupational disease in the United States. This employer-based surveillance system is inadequate for determining the frequency of occupational disease. Our analysis which combines a readily-available and relatively inexpensive national administrative database (i.e., death certificates) with a more costly state-based active surveillance system is a cost-effective model that could be used to provide better estimates of a number of different occupational diseases. Accurate estimates of occupational illnesses are essential to both determine temporal trends and evaluate efforts to prevent silicosis.

Mortality of mental disorders in relation to potential pesticide exposure.

Some studies have suggested a role of pesticide exposure in the development of neurobehavioral disorders. This case-control study examined the association between mortality from mental disorders and occupational exposure to pesticides. The study population consisted of 7756 deaths and 330,452 eligible controls identified from US death certificate files for the years 1988 through 1992. Exposure assignment was based on job title reported on the death certificates. Employment in jobs potentially involving pesticide exposure was weakly associated with the risk of death from mental disorders (odds ratio [OR] = 1.46; 95% confidence interval (95% CI) = 1.33-1.60). This association was stronger among women (OR = 2.65; 95% CI = 1.89-3.71), in particular for deaths from neurotic disorders (OR = 4.32; 95% CI = 2.44-7.64). These results must be interpreted with caution, however, because the impact of social and work-related factors other than pesticide exposure is not known.

Industries and cancer.

Epidemiologic evidence on the relationship between selected industries and cancer is reviewed. This article will focus on several industries which have not been covered elsewhere in this volume, briefly describe current research on cancer in the agricultural and construction industries, and discuss surveillance data on cancer mortality in relation to industry listed on US death certificates. Employment in the rubber industry has been associated with bladder cancer, leukemia, stomach, and lung cancer and is considered by the International Agency for Research on Cancer (IARC) to have 'sufficient evidence of carcinogenicity in humans.' Studies of workers exposed to polychlorinated biphenyls (PCBs) have reported excess mortality from gastrointestinal neoplasms, hematologic neoplasms, and skin cancer (specifically malignant melanoma); IARC considers that the evidence for carcinogenicity in humans is 'limited.' Employment in the boot and shoe industry has been associated with nasal adenocarcinomas in England and Italy ('sufficient'). Hairdressers and barbers have been found to have excess bladder cancer and less consistent evidence for several other sites ('limited'). Workers exposed to wood dust have excess mortality from cancer of the nasal sinuses and paranasal cavities; there is less consistent evidence for excess laryngeal cancer ('sufficient'). Workers employed in the petroleum industry have limited evidence for excess leukemia and other lymphatic and hematopoietic neoplasms, and skin cancer (particularly malignant melanoma) ('limited').

Use of multiple-cause mortality data in epidemiologic analyses: US rate and proportion files developed by the National Institute for Occupational Safety and Health and the National Cancer Institute.

The authors have created US mortality rates (age, sex, race, and calendar-time specific) and proportions, using multiple cause-of-death data, for the years 1960-1989. Multiple cause-of-death data include the usual underlying cause of death from the death certificate as well as contributory causes and other significant conditions. US multiple-cause rates and proportions enable the user to calculate the expected occurrences of disease on the death certificates of a cohort under study. There is an average of 2.66 causes and/or contributory conditions listed on US death certificates, increasing over time from 2.54 in the 1960s to 2.76 in the 1980s. The ratio of multiple-cause listings to underlying cause listings varies by disease, from low ratios for cancers to high ratios for diseases such as diabetes, arthritis, prostate disease, hypertension, pneumoconiosis, and renal disease. Use of these data is illustrated with two cohorts. Multiple-cause analysis (but not underlying cause analysis) revealed twofold significant excesses of renal disease and arthritis among granite cutters. For workers exposed to dioxin, neither multiple-cause nor underlying cause analysis indicated any excess of diabetes, an outcome of a priori interest. Good candidates for multiple-cause analysis are diseases that are of long duration, not necessarily fatal, yet serious enough to be listed on the death certificate.

Locations of fatal work injuries in the United States: 1980 to 1985.

Surveillance of injury at work is beset with problems of method and definition. As a result, national agencies have widely varying estimates of the number of fatal work injuries in the United States. One plausible method for identifying fatal work injuries is to use the Place of Injury variable, which is entered on all US death certificates but is not encoded by the National Center for Health Statistics. To use this method, one would assume that work injuries largely occur at "typical work sites," ie, places coded as industrial, farm, and mine and quarry. Data to test this method were derived from the National Traumatic Occupational Fatality data base maintained by the National Institute for Occupational Safety and Health. Analysis of this data base showed that work-related fatal injuries mostly occur in places where many non-work-related injuries also occur. Only about one third of fatal work injuries took place at locations coded as industrial, farm, and mine and quarry. As a method for identifying fatal work injuries, the Place of Injury variable appears to have little value.

Conditions associated at death with specific types of completed stroke in patients with and without hypertension: a case-control study.

Potential risk factors for various types of stroke were studied using a case-control study design. All 1978 US death certificates for which the registered underlying cause of death was subarachnoid hemorrhage (SAH), cerebral hemorrhage (CH), or cerebral infarction (CI) were identified. The frequency with which other conditions appeared on the death certificates of cases with and without hypertension was compared with controls. These data provide new information, such as the occurrence of peripheral vascular disease in association with SAH, the risk of CH in epileptic and cirrhotic patients, and the association of benign neoplasms of the nervous system, motor neuron disease, and 'paralysis agitans' with CI.

Nervous System Tumors: Case-Control Study of Associated Conditions at the Time of Death

All 1978 US death certificates for which the registered underlying cause of death was nervous system (NS) tumors were identified (n = 9,841). For each case, 2 control deaths were matched by age, race,