Determinants of the excessive rates of lung cancer in northeast Florida.

BACKGROUND: Age-adjusted rates of lung cancer among whites, but not blacks, in Duval County Jacksonville), Florida, have been among the highest of any metropolitan area of the United States for three decades. METHODS: We conducted a case-control study, interviewing 507 patients with lung cancer diagnosed from 1993 to 1996 and 1,007 control subjects, randomly selected from the county population. RESULTS: Cigarette smoking was the dominant cause of lung cancer (odds ratios, 59 among male current smokers; 30 among female current smokers). Both prevalence and intensity of smoking were excessive for whites but less for blacks when compared with national norms. Little association was found with residential patterns, indices of air quality, or occupation. Risk doubled with increased intake of dietary fat and with a family history of lung cancer. CONCLUSIONS: Life-style factors, especially smoking, but not environmental factors, appear responsible for the high rates of lung cancer in northeast Florida.

Southern cooking and lung cancer.

Dietary associations were examined as part of a case-control study exploring reasons for exceptionally high rates of lung cancer in northeast Florida. Interviews, which included a nationally standardized food frequency questionnaire, were conducted with 507 patients diagnosed with lung cancer during 1993-1996 or their next of kin and 1,007 persons of similar age, race, and gender randomly selected from the general population. A substantial reduction in risk was associated with high consumption of nutrient-dense fruits and vegetables. Risk was nearly doubled among men and women in the highest quartile of fat intake. The effects were most prominent for saturated and monounsaturated fats and not apparent for polyunsaturated fat consumption. Increased risk was linked to consumption of several individual high-fat foods, including some traditional Southern foods or methods of cooking, such as cooking vegetables with lard/fatback/bacon fat. Reported use of vitamin/mineral supplements was associated with decrease risk of lung cancer as well as dietary consumption of vitamins A, C, and E and some carotenoids. The findings are consistent with emerging evidence that risk of lung cancer rises with increasing dietary fat consumption. They indicate the need for further research to determine whether the association between fat intake and lung cancer is causal and, if so, to clarify the relationships with individual fat fractions.

Tobacco smoking: a survey in a community with excess lung cancer.

Duval County, Florida (Jacksonville) has had one of the highest lung cancer mortality rates among large US cities in recent decades. This survey was conducted to determine whether this might be due in part to higher prevalence or amount of smoking. Telephone interviews using a random digit dialing technique were conducted with 3,105 residents. Questions on cigarette smoking were taken from national surveys, and Jacksonville rates were compared with US rates. The percentage of persons in Jacksonville who had ever smoked was similar to the national percentage. Among whites, however, the prevalence of current smokers was slightly higher, and of heavy smokers was significantly higher, than national rates for whites; while among blacks, smoking prevalence and amount were below national rates for blacks. Up to one third of the excess lung cancer mortality rates in male and female whites in Jacksonville might be accounted for by the heavier amounts smoked by residents.

Epidemiologic methods for selective surveillance.

To allow time for problem-solving and staff education aimed at the prevention of future nosocomial infections, it is necessary for infection control practitioners to decrease the quantity of data-gathering activities and increase the quality of data analysis and action based on the data. A system by which certain high-risk patient groups and life-threatening infection sites are monitored by continuous surveillance every month, but other units and sites are selected on a rotating basis for periodic study, has been called "selective surveillance" and used at our 500-bed medical center for eight years. The system is backed by an essential third component: a network of inspections with prevalence studies, prospective studies of medical and surgical procedures, retrospective studies of sites with low endemic rates, and immediate investigations of clusters of infection. Success of this system is based on good daily communication with laboratory and nursing personnel and use of sound epidemiologic methods.

Mortality among rubber workers: Relationship to specific jobs.

This study has examined the ten-year mortality in a single-plant population of 6678 male rubber workers, in terms of the association of specific causes of death with a history of having worked in certain categories of jobs within the rubber industry. The work-histories of individual study subjects were analyzed, in detail, for all workers dying of selected causes of death. Comparison was made with the work-histories of a 22% age-stratified random sample of the total population. Age-adjusted exposure ratios (Tables 3 and 4) were calculated for all nine case groups in all 16 work areas, using differing exposure criteria (i.e. duration and calendar period). These ratios provide an approximation of the increased mortality risk associated with particular work areas. The risk ratios (with their associated confidence intervals), in Table 5, provide more rigorous estimates of these instances of increased mortality risk. For each cause of death studied, there were statistically significant associations with several work areas. For the cancers, the strongest associations tended to be with work areas at the front end of the production line (especially compounding and mixing), where the likelihood of contact with dusts, chemical ingredients, and vapors containing the early reaction byproducts, is high. The reclaim operation and the synthetic plant were each associated with several cancers (respiratory and bladder, and stomach and lymphato-hematopoietic cancers, respectively). The lymphatic leukemias were associated with solvent-exposure areas, especially inspection, finishing, and repair. Ischemic heart disease deaths, at ages 40-54, were strongly associated with having worked in extrusion and tread cementing, and in the synthetic plant. Deaths from diabetes mellitus were strongly associated with the janitoring-trucking category, and with jobs in the inspection, finishing and repair area. These observed associations, calculated after controlling for the variables sex and age, were apparently not due to confounding by smoking and race differences between work areas. The role of selective transfer of sick individuals (into, say janitoring or trucking) warrants further investigation. However, this mechanism is unlikely to be involved in the great majority of the observed associations. Another possible source of spurious inferences of increased risk would be correlation, within work-histories, between two job categories, one of which actually involved increased risk, while the other did not. Such associations could occur if certain job sequency trends existed within this working population. (Preliminary analyses indicate that this likelihood is not great; however, further analysis is planned.) Detailed study of specific environmental agents, historically and cross-sectionally, is currently underway, in an attempt to identify the work-environment agents responsible for the associations reported here.