TABLE 3.
ORs (95% CIs) for colorectal adenoma according to the rs2855798 polymorphism in KCNJ1 and the rs1531916 polymorphism in SLC12A1 stratified by calcium intake: the Tennessee Colorectal Polyp Study1
| Adenomas vs. controls |
Multiple/advanced adenomas vs. controls |
|||||
| Number of genes with variant alleles | Cases/controls | OR (95% CI) | P-trend | Cases/controls | OR (95% CI) | P-trend |
| n/n | n/n | |||||
| All subjects | 0.59 | 0.40 | ||||
| 0 | 528/1131 | 1.00 | 215/1131 | 1.00 | ||
| 1 | 560/1272 | 0.92 (0.79, 1.07) | 250/1272 | 1.04 (0.84, 1.29) | ||
| 2 | 158/334 | 0.99 (0.78, 1.25) | 73/334 | 1.15 (0.84, 1.59) | ||
| Calcium intake <1000 mg/d | 0.03 | 0.001 | ||||
| 0 | 210/446 | 1.00 | 83/446 | 1.00 | ||
| 1 | 245/466 | 1.12 (0.88, 1.43) | 109/466 | 1.36 (0.96, 1.93) | ||
| 2 | 84/123 | 1.53 (1.07, 2.19) | 45/123 | 2.20 (1.36, 3.54) | ||
| Calcium intake ≥1000 mg/d | 0.008 | 0.08 | ||||
| 0 | 318/685 | 1.00 | 132/685 | 1.00 | ||
| 1 | 315/806 | 0.81 (0.66, 0.99) | 141/806 | 0.91 (0.69, 1.20) | ||
| 2 | 74/211 | 0.69 (0.50, 0.95) | 28/211 | 0.64 (0.40, 1.02) | ||
Phase I + phase II. Unconditional logistic regression models adjusted for age (continuous), sex, race (Caucasian, other), education (categorical), recruitment sites, BMI (categorical), smoking status (never, former, current), alcohol consumption status (never, former, current), physical activity (yes, no), and daily intakes of total energy and magnesium (continuous). P values for interactions between calcium intake (continuous) and combined single-nucleotide polymorphisms (rs2855798 in KCNJ1 and rs1531916 in SLC12A1) were 7.5 × 10−5 for adenomas and 9.9 × 10−5 for multiple/advanced adenomas. KCNJ1, potassium inwardly-rectifying channel, subfamily J, member 1; SLC12A1, solute carrier family 12 member 1.