Table I.
Distributions of selected characteristics among non-Hispanic white cases and controls, The Los Angeles Bladder Cancer Study
| Characteristics | Bladder cancer patients (n = 730)a |
Control subjects (n = 740)a |
Two -sided Pb |
|---|---|---|---|
| Age (years)c | 55.8 (7.2) | 55.7 (8.2) | 0.81 |
| Gender | |||
| Malesd | 578 (79.2) | 582 (78.7) | 0.79 |
| Femalesd | 152 (20.8) | 158 (21.4) | |
| Level of education |
|||
| High school graduates or belowd |
256 (35.0) | 184 (24.9) | <0.0001 |
| College (1–4 years)d | 337 (46.2) | 368 (49.7) | |
| Graduate schoold | 137 (18.7) | 188 (25.4) | |
| Cigarette smoking | |||
| Never smokersd | 134 (18.4) | 296 (40.0) | <0.0001 |
| Former smokersd | 279 (38.2) | 308 (41.6) | |
| Current smokersd | 317 (43.4) | 136 (18.4) | |
| Among all smokers | |||
| Age starting to smokec | 17.4 (4.4) | 17.9 (4.2) | 0.08 |
| Number of cigarettes per dayc | 27.3 (14.0) | 22.6 (12.7) | <0.0001 |
| Number of years of smokingc | 29.6 (12.0) | 23.8 (12.9) | <0.0001 |
| Number of pack-years of smokingc |
42.1 (28.2) | 28.8 (23.9) | <0.0001 |
| Alcohol drinking | |||
| Non-drinkersd | 191 (26.2) | 211 (28.5) | 0.31 |
| Regular drinkersd | 539 (73.8) | 529 (71.5) | |
| Among drinkers | |||
| Number of drinks per dayc | 23.7 (33.5) | 21.4 (31.2) | 0.24 |
| Number of years of drinkingc | 28.2 (13.4) | 28.5 (11.7) | 0.75 |
| Ever held a high-risk jobe | |||
| Nod | 620 (84.9) | 665 (89.9) | 0.004 |
| Yesd | 110 (15.1) | 75 (10.1) | |
| Ever used permanent hair dyesf | |||
| Non-usersd | 81 (53.3) | 104 (65.8) | 0.02 |
| Regular usersd | 71 (46.7) | 54 (34.2) | |
| 4-ABP–Hb adducts (pg/g) in tertileg | |||
| Low (<17.9)e | 137 (20.6) | 235 (34.2) | <0.0001 |
| Intermediate (17.9–30.0)e | 164 (24.6) | 230 (33.5) | |
| High (>30)e | 365 (54.8) | 222 (32.3) |
Including 730 cases and 740 control subjects in all analysis except for those indicated below (see details in the Statistical Analysis section).
t-test for continuous variables and chi-square test for categorical variables.
Mean (standard deviation).
Number of subjects (column percentage).
High-risk job includes hair dresser; barber; truck, bus or taxi driver and aluminum product worker.
Among women only (152 cases and 158 controls); regular users of permanent hair dye for 1 year or longer; among regular users, the mean (standard deviation) years of hair dye use for bladder cancer patients and control subjects were 22.6 (9.8) and 19.5 (11.9), respectively.
Including 666 cases and 687 control subjects with available measurements of 4-ABP–Hb adducts.