Table 1.
Characteristics* of colorectal cancer cases and controls
| Cases n = 2,033 | Controls n = 9,640 | P * | ||
|---|---|---|---|---|
| Age at case diagnosis or control blood draw, years | 70.0 (8.6) | 68.0 (8.6) | <.0001 | |
| Sex, n (%) | .29 | |||
| Male | 1125 (55%) | 5260 (55%) | ||
| Female | 908 (45%) | 4380 (45%) | ||
| Ethnicity, n (%) | .002 | |||
| White | 381 (19%) | 1915 (20%) | ||
| African American | 406 (20%) | 2474 (26%) | ||
| Japanese American | 694 (34%) | 2623 (27%) | ||
| Latino | 439 (22%) | 1984 (21%) | ||
| Native Hawaiian | 113 (6%) | 644 (7%) | ||
| Education, years of school | 13.2 (3.0) | 13.6 (3.1) | .0002 | |
| Body mass index (BMI), kg/m2 | 27.2 (4.9) | 26.8 (4.8) | <.0001 | |
| Family history of colorectal cancer, % yes | 219 (11%) | 876 (9%) | .05 | |
| History of intestinal polyps, % yes | 131 (6.4%) | 659 (6.8%) | .10 | |
| Diabetes, % | 500 (24%) | 1928 (20%) | <.0001 | |
| Cigarette-smoking history, n (%) | .001 | |||
| Never | 762 (38%) | 4006 (42%) | ||
| Former | 954 (47%) | 4191 (44%) | ||
| Current | 300 (15%) | 1342 (14%) | ||
| Pack-years among ever smokers | 19.6 (16.7) | 17.9 (15.4) | .004 | |
| Physical activity, metabolic equivalents (METs) | 1.62 (0.29) | 1.62 (0.29) | .28 | |
| Aspirin, % current use | 418 (21%) | 2062 (21%) | .11 | |
| Multivitamin, % current use of ≥1/week | 926 (46%) | 4793 (50%) | .0005 | |
| Dietary intake** | ||||
| Alcohol, servings/day | 0.83 (2.15) | 0.66 (1.76) | .0003 | |
| Fiber, g/1000kcal/day | 11.6 (4.4) | 11.9 (4.3) | <.0001 | |
| Total calcium, mg/day | 958 (578) | 1010 (639) | .0002 | |
| Hormone treatment, % current use among women | 225 (25%) | 1520 (35%) | <.0001 | |
*
Mean (standard deviation) for continuous traits and number of subjects (percent) for categorical traits. P-values for case-control comparisons are from general linear models. All comparisons, other than for age, were adjusted for age.
**
Dietary intake of alcohol was compared in servings (14g ethanol per serving). Intake of dietary fiber was adjusted for total energy intake by nutrient density (per 1,000 kcal). Total intake of calcium from foods and supplements was not energy-adjusted.