Health Assessment Document for Diesel Emissions - NSCEP | US ...

1 the confined space of a truck cab, all of which are lifestyle factors specific to the truck-driving
2 occupation.
3
4 8.4.3. Hoar and Hoover (1985): Truck Driving and Bladder Cancer Mortality in
5 Rural New England
6 This study investigated the relationship between the occupation of truck driving and
7 bladder cancer mortality in a case-control study in New Hampshire and Vermont. Cases
8 included all white residents ofNew Hampshire and Vermont who died. from bladder cancer
9 (eighth revision ofthe ICD) between 1975 and 1979. Death certificates were provided by the
1 0 vital records and health statistics office of the two States, and the next of kin were traced and
11 interviewed in person. Two types of controls were selected for each case. One control was
12 randomly selected from all other deaths, excluding suicides, and matched on State, sex, race, age
13 (±2 years), and year of death. The second for control was selected with the additional matching
14 criteria of county of residence. Completed interviews were obtained from 325 (out of 41 0) next
15 of kin for cases and 673 (out of 923) for controls. Information on demographic characteristics,
16 lifetime occupational and residential histories, tobacco use, diet, and medical history was
17 obtained on each subject. The odds ratio was calculated to ascertain a measure of association
18 between truck driving and bladder cancer. Because separate analyses of the two control series
19 gave similar results, the two control series were combined. Also, because matched analyses ·
.20 yielded results similar to those provided by the unmatched analyses, results of the unmatched
21 analyses were presented.
22 Sixteen percent (35) of the cases and 12% (53) of the controls had been employed as
23 truck drivers, yielding an odds ratio of 1.5 (95% CI = 0.9, 2.6) after adjustment for county of
24 residence and age at death. For New Hampshire, the odds ratio was 1.3 (95% CI = 0.7, 2.3), and
25 for Vermont, the odds ratio was 1.7 (95% CI = 0.8, 3.4). For a large number of subjects, the next
26 of kin were unable to give the durations of truck driving, and there was an inconsistent positive
27 association with _Years of truck driving. Crude relative odds were not altered after adjustment for
28 coffee drinking, cigarette smoking, and education as a surrogate for social class. Little variation
29 in risks was seen when the data were analyzed by the industry in which the men had driven
30 trucks. No relationship was seen between age at which employment as a truck driver started and
31 occurrence of bladder cancer. Analysis by duration of employment as a truck driver and bladder
32 cancer showed a positive trend of increasing relative odds with increasing duration.of
33 . employment. The trend test was statistically significant (p=0.006). The odds ratio was
34 statistically significant for the 5 to 9 years of employment category only (OR= 2.9, 95% CI =
35 1.2, 6.7). ·Similarly, analysis by calendar year first employed showed a statistically significant
2/1/98 8-46 DRAFT--DO NOT CITE OR QUOTE