Current Trends Use of Death Certificates for Surveillance of Work-Related Illnesses -- New Hampshire

To conduct surveillance for occupationally related health events, some state health departments have made innovative use of the limited data sources available to them locally (e.g., death certificates, workers' compensation claims, hospital discharge files) (1). The New Hampshire Division of Public Health Services (NHDPHS) of the State Department of Health and Human Services recently completed a study of death certificates in the state for 1963-1983 to epidemiologically characterize deaths due to mesothelioma and the pneumoconioses (silicosis, asbestosis, and anthracosis).

Death certificates were provided by New Hampshire's Bureau of Vital Health Statistics for 1963-1983 and were reviewed to obtain information on all deaths for which mesothelioma or a pneumoconiosis was recorded as the underlying or contributing cause of death. Information was abstracted from these certificates on sex, occupation, age at death, year of death, and usual place of residence. Data were analyzed to estimate the prevalence of these conditions, to determine the demographic characteristics of the cases, and to describe the geographic distribution of these conditions within New Hampshire (Figure 1).

Mesothelioma was recorded on 13 death certificates, nine for males (average age at death: 65 years) and four for females (average age at death: 69 years). In eight cases, the mesotheliomas were pleural in origin; five occurred in the abdominal cavity. The average length of survival following diagnosis was 10 months for males and 4 months for females. For seven of the cases, occupational exposure to asbestos was likely to have occurred. The remaining cases occurred among persons whose primary occupations at time of death were recorded as housewives, a lawyer, and an insurance broker.

Silicosis was recorded as a cause of death on 22 death certificates (average age at death: 70 years); three of these were silicotuberculosis. All cases involved males employed in industries associated with a potential for exposure to silica dust.

Asbestosis was listed for nine deaths as the cause of death (average age at death: 74 years). The eight male workers were employed in trades with a potential for asbestos exposure; the female was identified as a housewife. Deaths associated with asbestos exposure (both mesothelioma and asbestosis) were clustered in geographic areas where the industrial use of asbestos is known to have occurred (Figure 1).

Anthracosis (i.e., coal workers' pneumoconiosis) was recorded as the cause of death for a coal miner and a crane operator. The death of one worker who was involved in the manufacture of woven belts was attributed to byssinosis (not usually classified as a pneumoconiosis), and three deaths were listed as "pneumoconiosis-unspecified."

An additional 218 death certificates indicated pulmonary fibrosis or interstitial fibrosis as a cause of death. Of these, 39 involved occupations with a high probability of past exposure to silica or asbestos (e.g., construction, shipbuilding, and manufacturing). Of the remainder, 15 cases involved work in the shoe or leather trades; 11 worked with wood or paper products; six were farmers; four worked with textiles; and four were painters; the remainder were unspecified. Reported by E Schwartz, MD, State Epidemiologist, and staff, New Hampshire State Dept of Health and Human Svcs; National Institute for Occupational Safety and Health, CDC.

Editorial Note

Editorial Note: NHDPHS elected to study deaths associated with mesothelioma and the pneumoconioses because these diseases are considered sentinel health events (occupational) (SHE(O)). A sentinel health event is defined as a preventable disease, disability, or untimely death, the occurrence of which serves as a warning signal that the quality of preventive activities and/or therapeutic medical care may need to be improved (2); a SHE(O) is an occupationally related sentinel disease. Mesothelioma and the pneumoconioses were specifically targeted for this study because: (1) the relationship is clearly established between these health conditions and exposure to dusts (e.g., asbestos, silica, coal) encountered in the workplace or general environment; and (2) recognition of a single case of these diseases justifies a careful search for other cases and raises important questions about their occurrence and the prevention of additional cases.

Mesothelioma is a tumor arising from the pleura or the peritoneum. A strong relationship has been established between the occurrence of mesothelioma and previous exposure to asbestos dust (3) among exposed workers, family contacts of asbestos-exposed workers, and persons incidentally exposed to airborne asbestos at work or from waste dumps, factories, construction sites, and automobile- or truck-brake linings. As with most chemically induced cancers, the latency period between the time of first exposure to asbestos and the clinical detection of mesothelioma is usually 20 years or more.

The pneumoconioses result from the inhalation and accumulation of dust in the lungs or from the reaction of the tissues to its presence (4). Although the inhalation of house dusts and most other dusts does not result in pneumoconiosis, the inhalation over long periods of time of silica, asbestos, and coal dust may result in pulmonary fibrosis. A pneumoconiosis may be suspected from the patient's occupational and medical history and is often diagnosed with the aid of chest radiographs and pulmonary-function tests.

For several reasons, this death certificate-based survey may have underestimated the magnitude of mortality associated with exposure to fibrogenic dusts. First, the long latency period usually associated with these diseases often hinders determination of their relationship to work. Accurate diagnosis requires that physicians consider the possible occupational or environmental origins of disease. A practical and systematic approach to such diagnoses has been devised (5). A key element is the occupational history, which should include details on various jobs held and information on chemical or physical exposures encountered during a patient's working lifetime (6). Second, because the clinical presentations of occupationally and nonoccupationally related diseases are often similar, it is not always clear whether certain diseases result from occupational exposure. Third, other potentially asbestos-related cancers (e.g., oropharyngeal, gastrointestinal, lung, or renal cancer) were not included in this survey. Fourth, because death certificates provide limited information on the decedent's occupational history, associations with specific occupations could not be determined for many of the cases. For example, approximately 10% of the death certificates listing pulmonary fibrosis or interstitial fibrosis as a cause of death also list occupation as "retired" or "at home." Fifth, based on the limited clinical and historic information on the death certificates, it is difficult to determine which cases of pulmonary fibrosis or interstitial fibrosis should be diagnosed as pneumoconioses. For the purposes of epidemiologic analysis, a pneumoconiosis was assumed if occupational information indicated exposure to asbestos or silica.

Investigation and follow-up of these sentinel health events may provide improved opportunity for prevention. Effective prevention of future pneumoconiosis and mesothelioma cases depends on: (1) recognition of work places where hazardous exposures are now occurring; (2) substitution of less hazardous substances for hazardous materials; (3) use of appropriate engineering controls, including local exhaust ventilation; (4) implementation of safe work practices; and (5) use of personal protective devices, such as respirators.

Effective surveillance and prevention depend on prompt reporting of pertinent diagnoses by those in the health-care community. Although in New Hampshire practicing health-care providers are required to report all cases of occupationally related disease to the state's Division of Public Health Services (7), relatively few cases are ever actually reported. It is essential, therefore, that health-care providers consider the potential occupational or environmental relatedness of diseases and report these diseases in conformance with reporting requirements.

References

1. CDC. Excavation cave-in fatalities--Texas, 1976-1985. MMWR 1986;35:313-4.

2. Rutstein DD, Mullan RJ, Frazier TM, Halperin WE, Melius JM, Sestito JP. Sentinel health events (occupational): a basis for physician recognition and public health surveillance. Am J Public Health 1983;73:1054-62.

3. Selikoff IJ, Lee DH. Asbestos and disease. New York: Academic Press, 1978.

4. International Labor Organization. Encyclopedia of occupational health and safety. 3rd ed. Geneva International Labor Organization, 1983.

5. Goldman RH, Peters JM. The occupational and environmental health history. JAMA 1981;246:2831-6.

6. The Occupational and Environmental Health Committee of the American Lung Association of San Diego and Imperial Counties. Diagnosis and treatment: taking the occupational history. Ann Intern Med 1983;99:641-51.

7. New Hampshire Division of Health and Welfare. R.S.A. He-P 301.1

Disclaimer   All MMWR HTML documents published before January 1993 are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

Page converted: 08/05/98

HOME  |  ABOUT MMWR  |  MMWR SEARCH  |  DOWNLOADS  |  RSS |  CONTACT POLICY  |  DISCLAIMER  |  ACCESSIBILITY

Morbidity and Mortality Weekly Report Centers for Disease Control and Prevention 1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A Department of Health and Human Services

This page last reviewed 5/2/01