Table 3. HRs for CRC-specific mortality among patients with colorectal cancer by quintile of post-diagnosis dietary insulin index stratified by predictors of patient outcome.
|
Dietary insulin index |
|||||||
|---|---|---|---|---|---|---|---|
| Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | ||||
| Stratification covariate | No. of patients | Quintile 1 | HR (95% CI)a | HR (95% CI)a | HR (95% CI)a | HR (95% CI)a | Pinteraction |
| Age at diagnosis, yearsb | 0.56 | ||||||
| ⩽67 | 999 | Referent | 1.39 (0.84–2.29) | 1.50 (0.91–2.47) | 1.92 (1.16–3.17) | 1.79 (1.04–3.07) | |
| >67 | 1007 | Referent | 0.90 (0.49–1.67) | 1.09 (0.61–1.96) | 1.24 (0.71–2.18) | 1.44 (0.82–2.54) | |
| Sex | 1.00 | ||||||
| Female | 1314 | Referent | 0.99 (0.62–1.58) | 1.24 (0.78–1.95) | 1.53 (0.97–2.42) | 1.58 (0.98–2.54) | |
| Male | 692 | Referent | 1.70 (0.86–3.37) | 1.50 (0.74–3.02) | 1.73 (0.89–3.39) | 1.81 (0.89–3.67) | |
| BMI, kg m−2 | 0.01 | ||||||
| <25.0 | 890 | Referent | 1.13 (0.69–1.85) | 0.80 (0.47–1.35) | 0.97 (0.57–1.63) | 1.14 (0.67–1.93) | |
| ⩾25.0 | 966 | Referent | 1.10 (0.55–2.22) | 2.24 (1.21–4.14) | 2.93 (1.59–5.40) | 2.32 (1.21–4.46) | |
| Physical activity, MET-h per weekb | 0.40 | ||||||
| ⩽10.2 | 917 | Referent | 1.47 (0.80–2.68) | 1.84 (1.02–3.31) | 2.28 (1.29–4.02) | 2.37 (1.30–4.30) | |
| >10.2 | 908 | Referent | 1.07 (0.57–2.00) | 0.98 (0.53–1.82) | 1.04 (0.55–1.97) | 1.47 (0.79–2.72) | |
| Alcohol intake, g d−1b | 0.38 | ||||||
| ⩽1.9 | 1011 | Referent | 0.76 (0.40–1.43) | 0.88 (0.47–1.62) | 1.09 (0.61–1.95) | 1.01 (0.56–1.82) | |
| >1.9 | 995 | Referent | 1.32 (0.82–2.13) | 1.45 (0.90–2.33) | 1.63 (0.99–2.69) | 2.26 (1.34–3.81) | |
| Diagnosis periodb | 0.82 | ||||||
| 1976–1997 | 1056 | Referent | 1.30 (0.78–2.16) | 1.28 (0.77–2.11) | 2.02 (1.24–3.31) | 1.60 (0.94–2.72) | |
| 1998–2010 | 950 | Referent | 0.99 (0.54–1.82) | 1.53 (0.85–2.76) | 0.96 (0.52–1.79) | 1.72 (0.97–3.07) | |
| Time between diagnosis and dietary assessment, years | 0.14 | ||||||
| 0<2 | 1105 | Referent | 1.15 (0.72–1.83) | 1.52 (0.96–2.43) | 1.54 (0.98–2.43) | 2.11 (1.33–3.37) | |
| 2–4 | 901 | Referent | 1.21 (0.61–2.41) | 1.17 (0.61–2.24) | 1.68 (0.86–3.27) | 1.05 (0.51–2.18) | |
| Stage | 1.00 | ||||||
| I/II | 1204 | Referent | 1.44 (0.71–2.88) | 1.83 (0.92–3.63) | 2.12 (1.09–4.12) | 1.63 (0.80–3.34) | |
| III/IV | 573 | Referent | 1.21 (0.73–2.00) | 1.17 (0.71–1.92) | 1.38 (0.83–2.29) | 1.73 (1.05–2.83) | |
| Grade of tumour differentiation | 0.17 | ||||||
| Well/moderate | 1416 | Referent | 1.15 (0.69–1.92) | 1.63 (1.01–2.63) | 1.81 (1.12–2.92) | 2.05 (1.24–3.39) | |
| Poor | 265 | Referent | 1.62 (0.76–3.42) | 1.09 (0.51–2.37) | 0.97 (0.42–2.25) | 1.09 (0.43–2.74) | |
| Location of primary tumour | 0.75 | ||||||
| Colon | 1467 | Referent | 1.33 (0.82–2.17) | 1.56 (0.98–2.50) | 1.82 (1.14–2.90) | 1.79 (1.09–2.92) | |
| Rectum | 444 | Referent | 0.87 (0.44–1.73) | 0.88 (0.42–1.80) | 1.14 (0.57–2.27) | 1.35 (0.67–2.72) | |
Abbreviations: BMI=body mass index; CI=confidence interval; CRC=colorectal cancer; HR=hazard ratio; MET=metabolic equivalent.
a
Adjusted for age at diagnosis (continuous), sex, race (White, Black, other, unknown), smoking status (never, past, current, unknown), body mass index (<18.5, 18.5–24.9, 25.0–29.9, 30.0–34.9, ⩾35.0 kg m−2, or unknown), physical activity (quintiles or unknown), alcohol intake (0, 0.1–4.9, 5.0–14.9, ⩾15.0 g d−2), cancer stage (I–IV or unknown), grade of tumour differentiation (well, moderate, poor, unknown), location of primary tumour (proximal, distal, rectum, unknown) and year of diagnosis (continuous), excluding the stratification covariate.
b
Cutpoints chosen based on median values.