Table 2.
Post-diagnostic intake of fiber from different food sources and mortality among colorectal cancer patients (n=1,575)*
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | HR (95% CI) per 5 g/day |
P for trend | |
|---|---|---|---|---|---|---|
| CRC-specific mortality (n=174) | ||||||
| Cereal fiber | ||||||
| Median intake (interquartile range), g/day | 3.3 (2.7 to 3.8) | 5.1 (4.6 to 5.6) | 7.0 (6.4 to 7.6) | 10.2 (9.1 to 12.2) | ||
| No. of events | 52 | 47 | 40 | 35 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 0.80 (0.58-1.10) | 0.71 (0.50-1.00) | 0.60 (0.42-0.85) | 0.68 (0.53-0.89) | 0.004 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 0.75 (0.53-1.06) | 0.66 (0.45-0.97) | 0.57 (0.38-0.86) | 0.67 (0.50-0.90) | 0.007 |
| Vegetable fiber | ||||||
| Median intake (interquartile range), g/day | 3.3 (2.7 to 3.8) | 5.1 (4.6 to 5.5) | 6.9 (6.1 to 7.6) | 10.1 (8.6 to 12.3) | ||
| No. of events | 55 | 33 | 43 | 43 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 0.51 (0.36-0.74) | 0.57 (0.40-0.79) | 0.67 (0.48-0.93) | 0.81 (0.62-1.05) | 0.11 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 0.51 (0.34-0.75) | 0.65 (0.45-0.95) | 0.65 (0.44-0.98) | 0.82 (0.60-1.13) | 0.22 |
| Fruit fiber | ||||||
| Median intake (interquartile range), g/day | 1.8 (1.2 to 2.2) | 3.4 (2.9 to 3.7) | 5.1 (4.5 to 5.6) | 7.8 (6.8 to 9.9) | ||
| No. of events | 40 | 47 | 42 | 45 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 1.06 (0.74-1.51) | 0.94 (0.65-1.35) | 0.94 (0.65-1.34) | 0.91 (0.68-1.22) | 0.53 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 1.13 (0.77-1.66) | 1.00 (0.67-1.51) | 0.95 (0.61-1.46) | 0.91 (0.64-1.28) | 0.58 |
| All-cause mortality (n=773) | ||||||
| Cereal fiber | ||||||
| No. of events | 215 | 198 | 180 | 180 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 0.78 (0.66-0.92) | 0.74 (0.63-0.88) | 0.68 (0.57-0.80) | 0.77 (0.68-0.87) | <0.001 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 0.79 (0.67-0.94) | 0.76 (0.63-0.91) | 0.69 (0.57-0.84) | 0.78 (0.68-0.90) | <0.001 |
| Vegetable fiber | ||||||
| No. of events | 207 | 207 | 176 | 183 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 0.78 (0.66-0.93) | 0.76 (0.64-0.90) | 0.72 (0.61-0.86) | 0.83 (0.73-0.93) | 0.002 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 0.85 (0.71-1.02) | 0.81 (0.68-0.98) | 0.74 (0.61-0.91) | 0.83 (0.72-0.96) | 0.009 |
| Fruit fiber | ||||||
| No. of events | 189 | 195 | 175 | 214 | ||
| Age, sex, stage-adjusted HR (95% CI) † | 1 (referent) | 0.96 (0.81-1.14) | 0.82 (0.69-0.98) | 0.80 (0.67-0.94) | 0.83 (0.72-0.95) | 0.005 |
| Multivariable-adjusted HR (95% CI) ‡ | 1 (referent) | 1.06 (0.88-1.27) | 0.93 (0.77-1.13) | 0.93 (0.76-1.13) | 0.92 (0.78-1.08) | 0.29 |
Abbreviation: CI, confidence interval; HR, hazard ratio.
Post-diagnostic intake was assessed at least 6 months but no more than 4 years after diagnosis to minimize the influence of active treatment.
Cox proportional hazards regression model stratified by age groups at diagnosis (<60, 60-64, 65-69, 70-74, and ≥75 years), sex, and cancer stage (I, II, III, and unspecified), with additional adjustment for age at diagnosis (continuous).
Further adjusted for year of diagnosis (continuous), tumor grade of differentiation (1-3 and unspecified), subsite (proximal colon, distal colon, rectum and unspecified), pre-diagnostic fiber intake (in quartiles), post-diagnostic alcohol consumption (<0.15, 0.15-1.9, 2.0-7.4, ≥7.5 g/d), pack-years of smoking (0, 1-15, 16-25, 26-45, >45), BMI (<23, 23-24.9, 25-27.4, 27.5-29.9, ≥30 kg/m2), physical activity (women: <5, 5-11.4, 11.5-21.9, ≥22 MET-hours/week; men: <7, 7-14.9, 15-24.9, ≥25 MET-hours/week), regular use of aspirin (≥2 tablets per week), glycemic load, and consumption of total fat, folate, calcium, and vitamin D (in quartiles). Mutual adjustment was conducted by adjusting for fiber intake from other sources (i.e., except the one under examination).