Table 1.
Baseline characteristics of study participants in the WBF and UDCA Trials
| Baseline Characteristics | Pooled | WBF | UDCA | p value |
|---|---|---|---|---|
| N=2465 | N=1289 | N=1176 | ||
| Age at baseline (mean ± sd) | 0.321 | |||
| 66.0 ± 8.7 | 65.9 ± 8.8 | 66.2 ± 8.5 | ||
| Male, n (%) | 1668 (67.2) | 871 (67.0) | 797 (67.4) | 0.842 |
| White, n (%) | 2347 (95.3) | 1247 (95.9) | 1100 (94.6) | 0.12 |
| Family History CRC, n (%)3 | <0.001 | |||
| 545 (22.0) | 219 (16.9) | 326 (27.6) | ||
| Current Smoker (yes), n (%) | 0.24 | |||
| 315 (12.9) | 177 (13.6) | 138 (12.0) | ||
| Number of colonscopies(mean ± sd) | 0.27 | |||
| 1.8± 0.8 | 1.8 ± 0.9 | 1.8 ± 0.8 | ||
| Previous Polyps (yes), n (%)4 | <0.001 | |||
| 976 (40.3) | 450 (39.1) | 526 (47.1) | ||
| Aspirin Use (yes)5 | 0.78 | |||
| 693 (27.9) | 366 (28.2) | 327 (27.6) | ||
| Baseline Adenoma Characteristics | ||||
| Number > 1 (yes), n (%) | 1017 (41.0) | 559 (43.0) | 458 (38.8) | 0.03 |
| Large, n (%) | 1072 (43.5) | 573 (44.7) | 499 (42.2) | 0.22 |
| Villous histology, n (%) | 517 (21.0) | 272 (21.2) | 245 (20.8) | 0.78 |
| Proximal Location, n (%) | 747 (30.3) | 347 (27.1) | 400 (33.9) | <0.001 |
| BMI (kg/m2) | ||||
| Normal (% >18.5 & <25 kg/m2) | 739 (30.0) | 372 (28.9) | 367 (31.2) | |
| Overweight (% 25 – <30 kg/m2 ) | 1120 (45.4) | 593 (46.0) | 527 (44.8) | |
| Obese (%≥ 30 kg/m2) | 606 (24.6) | 324 (25.1) | 282 (24.0) | 0.44 |
| Waist (in.)6 | ||||
| Small, n (%) | 591 (26.1) | 352 (29.5) | 239 (22.4) | |
|
| ||||
| Medium, n (%) | 563 (24.9) | 289 (24.2) | 274 (25.7) | |
| Large, n (%) | 569 (25.2) | 294 (24.6) | 275 (25.8) | |
| Extra-Large, n (%) | 538 (23.8) | 259 (21.7) | 279 (26.2) | <0.001 |
1
Statistical tests for continuous variables comparing participants in WBF to participants in UDCA performed with a student’s t-test.
2
Statistical tests for categorical variables comparing participants in WBF to participants in UDCA performed with chi-square analyses.
3
History of colorectal cancer in one or more first degree relatives.
4
History of polyps prior to baseline
5
Aspirin use in the last month at baseline
6
Waist cutpoints for men (inches) small <36.5; medium 36.5–39.0; large 39.1–42.0; extra-large >42. Waist cutpoints for women (in) small <30.0; medium 30.0–33.0; large 33.2–37.0; extra-large >37.0. Numbers may not add up to total due to missing data.