Table 3.
Multivariable-adjusted relative risks (95 % CI)a for prostate cancer by fifth of plasma genistein concentration, subdivided by selected factors
| Fifth of genistein concentration (ng/ml) | p for trendc | p for heterogeneity of trendsd | |||||
|---|---|---|---|---|---|---|---|
| 1 (0.05–0.30) | 2 (0.40–1.30) | 3 (1.40–2.60) | 4 (2.70–6.00) | 5 (6.10–567.70) | |||
| Overall | |||||||
| Cases/controls (n) | 338/357 | 326/333 | 282/329 | 326/344 | 333/334 | ||
| RR (95 % CI) | 1 (reference) | 1.01 (0.81–1.26) | 0.86 (0.68–1.09) | 0.94 (0.74–1.19) | 0.98 (0.77–1.23) | 0.95 | |
| Adjusted RR (95 % CI)b | 1 (reference) | 1.03 (0.82–1.29) | 0.88 (0.69–1.12) | 0.95 (0.75–1.21) | 1.00 (0.79–1.27) | 0.82 | |
| Study phase | |||||||
| Phase 1 | |||||||
| Cases/controls (n) | 217/219 | 205/209 | 171/201 | 185/205 | 172/208 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.00 (0.76–1.34) | 0.81 (0.60–1.10) | 0.80 (0.59–1.08) | 0.74 (0.54–1.00) | 0.05 | <0.0001 |
| Phase 2 | |||||||
| Cases/controls (n) | 121/138 | 124/126 | 118/129 | 137/135 | 155/127 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.20 (0.81–1.76) | 1.12 (0.75–1.67) | 1.26 (0.84–1.87) | 1.57 (1.05–2.34) | 0.03 | |
| Stage of disease | |||||||
| Localized stage | |||||||
| Cases/controls (n) | 182/199 | 166/177 | 130/161 | 156/186 | 158/141 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.03 (0.76–1.41) | 0.84 (0.60–1.19) | 0.86 (0.62–1.20) | 1.13 (0.81–1.57) | 0.32 | 0.22 |
| Advanced stage | |||||||
| Cases/controls (n) | 67/71 | 61/56 | 57/61 | 66/67 | 65/73 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.20 (0.69–2.09) | 0.98 (0.56–1.72) | 0.96 (0.53–1.74) | 0.88 (0.50–1.55) | 0.42 | |
| Grade of disease | |||||||
| Low grade | |||||||
| Cases/controls (n) | 219/214 | 189/208 | 148/192 | 193/206 | 192/204 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 0.84 (0.62–1.13) | 0.67 (0.49–0.93) | 0.79 (0.57–1.09) | 0.79 (0.57–1.08) | 0.50 | 0.26 |
| High grade | |||||||
| Cases/controls (n) | 37/47 | 32/28 | 37/40 | 41/44 | 41/35 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.45 (0.66–3.18) | 1.28 (0.61–2.70) | 1.04 (0.49–2.21) | 1.57 (0.72–3.40) | 0.36 | |
| Age at blood collection | |||||||
| <60 years | |||||||
| Cases/controls (n) | 179/178 | 166/168 | 130/168 | 150/132 | 135/151 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 0.99 (0.73–1.36) | 0.74 (0.53–1.06) | 1.14 (0.80–1.63) | 0.87 (0.61–1.24) | 0.57 | 0.49 |
| ≥60 years | |||||||
| Cases/controls (n) | 150/151 | 154/153 | 147/155 | 174/202 | 194/176 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.00 (0.70–1.41) | 0.94 (0.67–1.34) | 0.82 (0.58–1.15) | 1.10 (0.78–1.55) | 0.36 | |
| Age at diagnosis | |||||||
| <60 years | |||||||
| Cases/controls (n) | 72/72 | 51/59 | 54/54 | 53/46 | 47/54 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 0.95 (0.54–1.67) | 1.01 (0.54–1.86) | 1.20 (0.66–2.19) | 0.74 (0.39–1.39) | 0.35 | 0.80 |
| ≥60 years | |||||||
| Cases/controls (n) | 266/285 | 275/274 | 228/275 | 273/298 | 286/280 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.05 (0.82–1.34) | 0.85 (0.65–1.10) | 0.91 (0.70–1.18) | 1.02 (0.79–1.33) | 0.66 | |
| Time between blood collection and diagnosis | |||||||
| <48 months | |||||||
| Cases/controls (n) | 100/104 | 80/94 | 92/95 | 94/78 | 110/112 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 0.96 (0.62–1.48) | 1.03 (0.66–1.60) | 1.25 (0.79–1.97) | 1.02 (0.66–1.56) | 0.97 | 0.86 |
| ≥48 months | |||||||
| Cases/controls (n) | 238/253 | 246/239 | 190/234 | 232/266 | 223/222 | ||
| Adjusted RR (95 % CI)b | 1 (reference) | 1.08 (0.82–1.41) | 0.82 (0.62–1.10) | 0.85 (0.64–1.14) | 0.98 (0.73–1.31) | 0.97 | |
aCase patients and control participants were matched on recruitment center, age at enrollment (±6 months), time of day of blood collection (±1 h), follow-up time (as close as possible), time between blood draw, and last consumption of food or drinks (<3, 3–6, >6 h)
bAdjustment was made for smoking (never, past, present), physical activity (inactive, moderately inactive, active), alcohol intake (<8, 8–15, 16–39, ≥40 g/day), marital status (married or cohabiting, not married or cohabiting), education (primary or none, secondary, degree level), and BMI (fourths)
cTest for trend obtained by replacing the categorical variable with a continuous variable equal to the median concentration within each fifth of plasma genistein concentration
dTest for heterogeneity between the trends obtained by replacing the categorical variable with a continuous variable equal to the median concentration within each fifth of plasma genistein concentration