Table 2.
ORs (95% CIs) of colorectal cancer ranked by quartile of serum TMAO
| OR (95% CI) by quartile of serum TMAO (µmol/L) | ||||||
|---|---|---|---|---|---|---|
| N | 1 (≤2.5) | 2 (>2.5–3.6) | 3 (>3.6 to 5.4) | 4 (>5.4) | P trend | |
| Colorectal cancer | ||||||
| No. cases/ No. controls |
644/644 | 154/167 | 159/166 | 163/156 | 168/155 | |
| Age and batch adjusted | 644/644 | 1.00 (Ref.) | 1.04 (0.76–1.42) | 1.14 (0.83–1.57) | 1.20 (0.86–1.68) | 0.26 |
| Fully adjusteda | 642/643 | 1.00 (Ref.) | 1.04 (0.76–1.42) | 1.15 (0.83–1.58) | 1.20 (0.86–1.68) | 0.25 |
| Cancer of the Proximal Colon | ||||||
| No. cases/ No. controls |
169/169 | 43/53 | 38/47 | 51/37 | 37/32 | |
| Age and batch adjusted | 169/169 | 1.00 (Ref.) | 0.99 (0.54–1.84) | 1.83 (0.99–3.41) | 1.60 (0.80–3.22) | 0.12 |
| Fully adjusteda | 169/169 | 1.00 (Ref.) | 1.00 (0.54–1.86) | 1.84 (0.99–3.43) | 1.60 (0.80–3.22) | 0.12 |
| Cancer of the Distal Colon | ||||||
| No. cases/ No. controls |
153/153 | 30/35 | 50/36 | 34/45 | 39/37 | |
| Age and batch adjusted | 153/153 | 1.00 (Ref.) | 1.63 (0.82–3.24) | 0.85 (0.41–1.78) | 1.22 (0.58–2.56) | 0.95 |
| Fully adjusteda | 152/153 | 1.00 (Ref.) | 1.73 (0.86–3.46) | 0.81 (0.38–1.70) | 1.21 (0.57–2.56) | 0.89 |
| Rectal Cancer | ||||||
| No. cases/ No. controls |
282/282 | 76/68 | 62/71 | 63/67 | 81/76 | |
| Age and batch adjusted | 282/282 | 1.00 (Ref.) | 0.77 (0.48–1.25) | 0.83 (0.50–1.36) | 0.97 (0.59–1.60) | 0.87 |
| Fully adjusted a | 281/281 | 1.00 (Ref.) | 0.76 (0.47–1.24) | 0.83 (0.50–1.36) | 0.94 (0.57–1.57) | 0.92 |
Logistic regression models adjusted for batch (categorical, 27 batches) and age (continuous). Quartiles of serum TMAO were based on the distribution among controls. Medians for each quartile (based on controls) were used in trend test; medians for TMAO quartiles 1 through 4 were 2.0, 3.1, 4.4 and 7.7, respectively. 2 participants had cancer of the proximal colon and rectum and are counted in both disease-stratified analyses.
Model additionally adjusted for the number of years smoked regularly (continuous), number of cigarettes smoked per day (continuous), education (college graduate, some college or technical school, versus ≤ high school), body mass index (continuous, kg/m2), heavy physical activity in leisure (yes/no), heavy occupational physical activity (yes/no), physical activity frequency (≥3 times per week, versus <3), total energy intake (continuous, kcal/day)