Table 1.
Descriptive characteristics of the study population by race
| Characteristic mean (SD) or n (%) | Caucasians (n = 913) | African Americans (n = 567) | p value |
|---|---|---|---|
| Age (years) | 55.1 (8.7) | 55.9 (8.7) | 0.08 |
| Gender | <0.001 | ||
| Male | 381 (41.7 %) | 171 (30.2 %) | |
| Female | 532 (58.3 %) | 396 (69.8 %) | |
| Body mass index (kg/m2) | 28.1 (6.0) | 32.0 (7.8) | <0.001 |
| Waist circumference (cm) | 37.6 (6.4) | 41.1 (7.3) | <0.001 |
| Waist/hip ratio | 0.90 (0.09) | 0.94 (0.08) | <0.001 |
| NSAID use | |||
| Non-user | 584 (64.0 %) | 363 (64.0 %) | 0.51 |
| User | 329 (36.0 %) | 204 (36.0 %) | |
| Smoking status | |||
| Never | 455 (49.8 %) | 204 (36.0 %) | <0.001 |
| Former | 360 (39.4 %) | 197 (34.8 %) | |
| Current | 98 (10.7 %) | 165 (29.2 %) | |
| Pack years of smoking | 10.1 (31.3) | 11.7 (22.8) | 0.28 |
| Family history of colorectal cancer | 235 (25.7 %) | 121 (21.3 %) | 0.03 |
| Insulin (μIU/mL) | 6.4 (8.4) | 11.7 (36.8) | 0.005 |
| Fasting glucose (mg/dL) | 85.7 (23.4) | 96.0 (35.4) | <0.001 |
| Advanced adenomaa | 39 (4.27 %) | 35 (6.17 %) | 0.10 |
The significance of the differences between cases and controls for categorical variables was assessed using a Pearson chi-square test and for continuous variables was assessed using an independent samples t test
a
Defined as if adenoma size ≥10 mm or high-grade dysplasia