Mortality patterns among men in the motor vehicle manufacturing industry

This retrospective follow-up study evaluates the mortality experience of 123,232 male hourly workers employed at a motor vehicle manufacturing company in 1973. Company computerized personnel records were used to identify subjects and to obtain their employment history. Follow-up through December 31, 1985 was conducted using company, state, and national data sources. The mortality rates of the cohort were compared with the rates of the United States (U.S.) general population of white or black men, adjusting for age and calendar time, and using the standardized mortality ratio (SMR) as the measure of association. The overall mortality rate of cohort members is lower than the U.S. rate by 11% among whites (11,060 observed/12,427 expected deaths; SMR = 89) and by 24% among blacks (3,744/4,926 deaths; SMR = 76). These low mortality rates reflect deficits of diseases other than cancer. Cancer SMRs are 99 for whites and 90 for blacks. There are slight excesses of stomach cancer (SMR = 113) and of lung cancer (SMR = 108) among whites and of cancer of the large intestine and rectum (SMR = 114) and of the lymphopoietic tissue (SMR = 111) among blacks. Both whites and blacks have a large deficit of buccal cancer and pharynx cancer, and blacks also have a deficit of esophagus cancer. The cohort's overall deficit of deaths is due largely to the favorable mortality experience of active workers. In contrast, white subjects who have left active employment have an 11% mortality excess, and inactive black subjects have a mortality rate that is similar to the general population rate. The increased mortality among inactive whites is not limited to any one particular disease category. This pattern may reflect illness-related employment termination and generalized confounding by socioeconomic status, although the study does not rule out a relationship between workplace exposures and specific diseases.