RESUMEN
Mesothelioma rates are declining toward background levels, although estimates of the background rate have varied. We expanded upon earlier analyses and provided a data-based estimate of the background rate. We analyzed US male and female patterns for five age groups using the National Cancer Institute's Surveillance Epidemiology and End Results registry data from 1973 to 2002. Age-specific and age-adjusted incidence rates per 1 000 000 persons per year, standardized to the 2000 US population, were calculated for total, pleural, and peritoneal mesothelioma. We also calculated rates for persons who attained working age after the US Occupational Safety and Health Administration asbestos exposure limits took effect. Mesothelioma rates observed among young males and females varied little over time. We observed a decline and convergence of recent male and female rates in older age groups, except those who are between the age of 60 and above, for whom the 2002 male rate was approximately five times greater than that of females. As expected, rates were higher in major shipyard areas on the West coast. Rates for persons with little or no opportunity for occupational asbestos exposure were 1.15 (95% confidence interval: 0.90-1.45) for men and 0.94 (95% confidence interval: 0.87-1.24) for women. Mesothelioma is rare in younger age groups, and rates have been relatively stable and similar for both sexes. Rates continue to decline in older age groups, but remain high for males at 60 years or older. Rates among females at older ages suggest an impact of occupational exposure. The background rate for persons below age 50 is approximately one per million, independent of sex. Future data are needed to estimate this rate for older age groups.
Asunto(s)
Mesotelioma/epidemiología , Neoplasias Pleurales/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Amianto/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mesotelioma/etiología , Persona de Mediana Edad , Exposición Profesional/estadística & datos numéricos , Neoplasias Peritoneales/epidemiología , Neoplasias Peritoneales/etiología , Neoplasias Pleurales/etiología , Caracteres Sexuales , Factores de Tiempo , Estados Unidos/epidemiología , Adulto JovenRESUMEN
BACKGROUND: The question of whether vehicle mechanics have an increased risk of mesothelioma has important public health implications. Calculations of relative risk using case reports from the Australian Mesothelioma Registry (AMR) indicate increased risks; however, this contrasts with the results of 19 epidemiologic studies that have found no association. AIM: To evaluate potential explanations for the discrepancy of findings from epidemiologic studies and AMR reports. METHODS: We evaluated three hypotheses as possible explanations for the inconsistency between the AMR-based calculations and the findings from published epidemiologic studies: (i) differences in exposure characteristics of Australian vehicle mechanics versus vehicle mechanics in North America and Europe, (ii) limitations of the AMR data and (iii) errors in the risk calculations based on AMR data. We reviewed available exposure information specific to Australian vehicle mechanics and AMR data, obtained from the Australian National Occupational Health and Safety Commission, for this evaluation. RESULTS: We did not identify differences in workplace exposures, processes or fibre type among Australian vehicle mechanics compared to vehicle mechanics in other countries. Our analysis of primary AMR data identified several errors in exposure classification and in the assumptions used to calculate relative risk. CONCLUSIONS: Discrepancies between epidemiologic studies and AMR-based calculations cannot be explained by differences in exposure. These discrepancies are most likely attributable to inadequate occupational information and classification in the AMR from 1986 forward and to erroneous assumptions used to derive relative risk estimates for mesothelioma among Australian vehicle mechanics.