Table 2.
Geometric means of plasma fatty acids and their desaturase indices among patients with colon or rectal cancer and their matched control subjects, the Singapore Chinese Health Study
| Colon | Rectal | |||||
|---|---|---|---|---|---|---|
| Cases (n = 211) | Controls (N = 211) | P-valuea | Cases (n = 139) | Controls (N = 139) | P- valuea | |
| Monounsaturated fatty acid (MUFA) synthesis pathway | ||||||
| Saturated fatty acids | ||||||
| Palmitic acid (16:0), µmol/dL | 265.82 | 282.64 | 0.078 | 277.74 | 269.14 | 0.415 |
| Stearic acid (18:0), µmol/dL | 92.62 | 97.32 | 0.097 | 96.74 | 93.88 | 0.369 |
| MUFAs | ||||||
| Palmitoleic acid (16:1), µmol/dL | 18.54 | 20.82 | 0.061 | 20.88 | 20.40 | 0.765 |
| Oleic acid (18:1), µmol/dL | 282.76 | 311.10 | 0.020 | 310.14 | 293.14 | 0.236 |
| Stearoyl-coenzyme A desaturase (SCD)-1 indices | ||||||
| Palmitoleic:Palmitic acid ratio | 0.06 | 0.08 | 0.221 | 0.08 | 0.08 | 0.881 |
| Oleic:Stearic acid ratio | 3.48 | 3.64 | 0.055 | 3.64 | 3.54 | 0.362 |
| n-3 Polyunsaturated fatty acids (PUFAs) | ||||||
| α-Linolenic acid (18:3), µmol/dL | 2.50 | 2.88 | 0.009 | 2.78 | 2.58 | 0.260 |
| Eicosapentanoic acid (20:5), µmol/dL | 3.52 | 3.48 | 0.862 | 3.48 | 3.52 | 0.873 |
| Docosahexaenoic acid (22:6), µmol/dL | 24.04 | 23.68 | 0.777 | 25.02 | 25.82 | 0.604 |
| n-6 PUFA synthesis pathway | ||||||
| n-6 PUFAs | ||||||
| Linoleic acid (18:2) (LA), µmol/dL | 569.04 | 600.26 | 0.044 | 591.76 | 570.82 | 0.286 |
| γ-Linolenic acid (18:3) (GLA), µmol/dL | 1.54 | 1.82 | 0.030 | 1.58 | 1.50 | 0.590 |
| Dihomo-γ-linolenic acid (20:3) (DGLA), µmol/dL | 7.38 | 8.06 | 0.064 | 7.88 | 7.20 | 0.154 |
| Arachidonic acid (20:4) (AA), µmol/dL | 73.16 | 69.72 | 0.207 | 75.80 | 71.38 | 0.210 |
| n-6 PUFA desaturase indices (DI) | ||||||
| GLA:LA ratio (for Δ6 DI) (×1000) | 2.7 | 3.2 | 0.137 | 2.6 | 2.6 | 0.869 |
| AA:DGLA ratio (for Δ5 DI) | 9.84 | 8.58 | 0.002 | 9.56 | 9.86 | 0.525 |
| AA:LA ratio (for total n-6 PUFA DI) (×1000) | 129 | 116 | 0.005 | 128 | 125 | 0.615 |
a P-value for difference between case and control groups were derived from one-way ANOVA for log-transformed measures of plasma fatty acids