Table II.
Selected demographic characteristics and major known risk factors for colorectal cancer by study groups, TCPS, 2003–2010
| Characteristic | Controls | Polyp cases | |||
|---|---|---|---|---|---|
| (N = 3336) | Adenoma only (N = 1160) | HPP only (N = 532) | Both (N = 368) | P valuea | |
| Study site (%) | |||||
| Vanderbilt University | 73.8 | 61.3 | 54.0 | 47.3 | <0.001 |
| Veterans Affairs | 26.2 | 38.7 | 46.0 | 52.7 | |
| Age [years, mean (SD)] | 57.2 (7.6) | 59.2 (7.4) | 57.1 (6.9) | 58.9 (6.5) | <0.001 |
| Sex (female, %) | 43.8 | 27.2 | 30.1 | 18.8 | <0.001 |
| Indications for colonoscopy (%)b | |||||
| Screening | 58.6 | 57.7 | 56.1 | 52.4 | 0.062 |
| Other | 41.4 | 42.3 | 43.9 | 47.6 | |
| Educational attainment (%)b | |||||
| High school or less | 24.5 | 29.7 | 33.1 | 37.7 | <0.001 |
| Some college | 28.7 | 27.0 | 31.4 | 38.5 | |
| College graduate | 20.4 | 21.9 | 18.5 | 12.7 | |
| Graduate or professional education | 26.5 | 21.4 | 17.0 | 11.0 | |
| Race (white, %) | 89.6 | 88.7 | 91.9 | 91.9 | 0.114 |
| Colorectal cancer family history (%)b | 8.4 | 9.9 | 8.1 | 10.4 | 0.378 |
| Regular cigarette smoking (%)b | 49.1 | 57.0 | 72.6 | 75.7 | <0.001 |
| Regular alcohol consumption (%)b | 43.1 | 47.0 | 50.7 | 45.2 | 0.009 |
| Body mass index (kg/m2, mean) | 28.1 | 28.7 | 28.8 | 29.1 | <0.001 |
| Regularly exercised (%)b | 57.5 | 52.8 | 53.3 | 48.0 | <0.001 |
| Regular NSAID use (%)b | 51.6 | 52.8 | 53.3 | 48.0 | 0.025 |
| Red meat intake (g/day, mean) | 57.4 | 73.4 | 79.8 | 85.3 | <0.001 |
Both, synchronous adenoma and HPPs.
aDerived from analysis of variance for continuous variables and chi-square test for categorical variables.
bStandardized by age (40–49, 50–59, 60–64 and ≥65 years) and sex distribution of all study participants.