Table 2.
Sex‐specific hazard ratio (95% confidence interval) of bladder cancer according to the intake of vegetables and fruits by quartile.
| Intake by quartile | P trend | ||||
|---|---|---|---|---|---|
| First | Second | Third | Fourth | ||
| Male (n = 37,061) | |||||
| Total vegetables and fruits | |||||
| Dietary intake, median (IQR) | 150 (106–184) | 268 (241–296) | 389 (356–427) | 600 (525–731) | |
| Person-years | 140,856 | 142,814 | 140,752 | 138,281 | |
| Number of cases | 60 | 78 | 84 | 85 | |
| IR per 100,000 person-years | 42.6 | 54.6 | 59.7 | 61.5 | |
| Model 1 HR (95% CI) | Ref | 1.17 (0.84–1.64) | 1.18 (0.84–1.64) | 1.08 (0.77–1.51) | 0.74 |
| Model 2 HR (95% CI) | Ref | 1.17 (0.83–1.65) | 1.18 (0.84–1.66) | 1.12 (0.79–1.58) | 0.60 |
| Total vegetables | |||||
| Dietary intake, median (IQR) | 78 (55–95) | 139 (125–153) | 202 (184–222) | 320 (278–399) | |
| Person-years | 140,935 | 141,110 | 141,688 | 138,970 | |
| Number of cases | 67 | 73 | 90 | 77 | |
| IR per 100,000 person-years | 47.5 | 51.7 | 63.5 | 55.4 | |
| Model 1 HR (95% CI) | Ref | 1.01 (0.72–1.41) | 1.15 (0.84–1.59) | 0.92 (0.66–1.29) | 0.82 |
| Model 2 HR (95% CI) | Ref | 0.98 (0.70–1.37) | 1.12 (0.81–1.55) | 0.92 (0.65–1.29) | 0.80 |
| Total fruits | |||||
| Dietary intake, median (IQR) | 36 (20–53) | 103 (87–120) | 177 (156–201) | 315 (265–410) | |
| Person-years | 140,146 | 142,802 | 141,358 | 138,397 | |
| Number of cases | 62 | 72 | 96 | 77 | |
| IR per 100,000 person-years | 44.2 | 50.4 | 67.9 | 55.6 | |
| Model 1 HR (95% CI) | Ref | 1.03 (0.73–1.45) | 1.30 (0.94–1.80) | 0.96 (0.68–1.34) | 0.89 |
| Model 2 HR (95% CI) | Ref | 1.03 (0.73–1.45) | 1.34 (0.96–1.86) | 1.00 (0.70–1.43) | 0.67 |
| Green and yellow vegetables | |||||
| Dietary intake, median (IQR) | 25 (16–33) | 56 (48–64) | 90 (80–101) | 153 (130–197) | |
| Person-years | 139,110 | 141,163 | 142,169 | 140,261 | |
| Number of cases | 76 | 70 | 85 | 76 | |
| IR per 100,000 person-years | 54.6 | 49.6 | 59.8 | 54.2 | |
| Model 1 HR (95% CI) | Ref | 0.88 (0.63–1.22) | 1.03 (0.75–1.40) | 0.88 (0.64–1.21) | 0.65 |
| Model 2 HR (95% CI) | Ref | 0.87 (0.62–1.20) | 1.00 (0.73–1.37) | 0.88 (0.63–1.23) | 0.67 |
| Cruciferous vegetables | |||||
| Dietary intake, median (IQR) | 19 (13–25) | 40 (35–45) | 63 (57–70) | 107 (91–137) | |
| Person-years | 141,132 | 141,223 | 140,759 | 139,589 | |
| Number of cases | 66 | 73 | 83 | 85 | |
| IR per 100,000 person-years | 46.8 | 51.7 | 59.0 | 60.9 | |
| Model 1 HR (95% CI) | Ref | 1.02 (0.73–1.43) | 1.07 (0.77–1.48) | 0.98 (0.71–1.36) | 0.96 |
| Model 2 HR (95% CI) | Ref | 1.00 (0.72–1.41) | 1.06 (0.76–1.47) | 0.98 (0.70–1.38) | 0.98 |
| Green leafy vegetables | |||||
| Dietary intake, median (IQR) | 8 (5–11) | 18 (16–21) | 31 (27–36) | 59 (49–78) | |
| Person-years | 138,185 | 141,120 | 141,432 | 141,966 | |
| Number of cases | 60 | 76 | 75 | 96 | |
| IR per 100,000 person-years | 43.4 | 53.9 | 53.0 | 67.6 | |
| Model 1 HR (95% CI) | Ref | 1.20 (0.86–1.69) | 1.13 (0.08–1.60) | 1.33 (0.96–1.85) | 0.13 |
| Model 2 HR (95% CI) | Ref | 1.17 (0.83–1.64) | 1.11 (0.78–1.57) | 1.34 (0.95–1.88) | 0.13 |
| Citrus fruits | |||||
| Dietary intake, median (IQR) | 7 (3–13) | 39 (30–47) | 75 (65–87) | 150 (120–208) | |
| Person-years | 141,199 | 143,116 | 141,369 | 137,019 | |
| Number of cases | 61 | 75 | 92 | 79 | |
| IR per 100,000 person-years | 43.2 | 52.4 | 65.1 | 57.7 | |
| Model 1 HR (95% CI) | Ref | 1.13 (0.80–1.59) | 1.35 (0.97–1.87) | 1.07 (0.76–1.50) | 0.53 |
| Model 2 HR (95% CI) | Ref | 1.14 (0.81–1.60) | 1.35 (0.97–1.88) | 1.11 (0.78–1.57) | 0.41 |
| Female (n = 43,891) | |||||
| Total vegetables and fruits | |||||
| Dietary intake, median (IQR) | 228 (174–267) | 363 (332–392) | 489 (454–528) | 706 (631–835) | |
| Person-years | 180,870 | 181,975 | 181,667 | 180,298 | |
| Number of cases | 15 | 26 | 23 | 30 | |
| IR per 100,000 person-years | 8.3 | 14.3 | 12.7 | 16.6 | |
| Model 1 HR (95% CI) | Ref | 1.58 (0.84–3.00) | 1.35 (0.70–2.60) | 1.67 (0.89–3.12) | 0.19 |
| Model 2 HR (95% CI) | Ref | 1.60 (0.84–3.05) | 1.36 (0.70–2.64) | 1.68 (0.88–3.20) | 0.21 |
| Total vegetables | |||||
| Dietary intake, median (IQR) | 104 (79–123) | 170 (155–185) | 235 (218–256) | 358 (313–436) | |
| Person-years | 179,396 | 180,938 | 182,330 | 182,147 | |
| Number of cases | 13 | 35 | 26 | 20 | |
| IR per 100,000 person-years | 7.2 | 19.3 | 14.3 | 11.0 | |
| Model 1 HR (95% CI) | Ref | 2.57 (1.36–4.86) | 1.82 (0.93–3.54) | 1.32 (0.65–2.67) | 0.99 |
| Model 2 HR (95% CI) | Ref | 2.59 (1.36–4.93) | 1.80 (0.91–3.54) | 1.31 (0.64–2.69) | 0.96 |
| Total fruits | |||||
| Dietary intake, median (IQR) | 76 (46-99) | 160 (140–179) | 244 (220–270) | 404 (345–507) | |
| Person-years | 181,485 | 182,553 | 181,901 | 178,870 | |
| Number of cases | 15 | 22 | 30 | 27 | |
| IR per 100,000 person-years | 8.3 | 12.1 | 16.5 | 15.1 | |
| Model 1 HR (95% CI) | Ref | 1.40 (0.72–2.71) | 1.82 (0.96–3.44) | 1.61 (0.84–3.10) | 0.13 |
| Model 2 HR (95% CI) | Ref | 1.42 (0.73–2.77) | 1.83 (0.96–3.49) | 1.63 (0.83–3.17) | 0.13 |
| Green and yellow vegetables | |||||
| Dietary intake, median (IQR) | 36 (26-45) | 69 (61–76) | 104 (94–115) | 171 (146–214) | |
| Person-years | 177,621 | 181,746 | 182,618 | 182,826 | |
| Number of cases | 14 | 31 | 25 | 24 | |
| IR per 100,000 person-years | 7.9 | 17.1 | 13.7 | 13.1 | |
| Model 1 HR (95% CI) | Ref | 2.14 (1.14–4.02) | 1.63 (0.84–3.14) | 1.48 (0.76–2.89) | 0.57 |
| Model 2 HR (95% CI) | Ref | 2.13 (1.13–4.03) | 1.60 (0.82–3.12) | 1.47 (0.75–2.90) | 0.62 |
| Cruciferous vegetables | |||||
| Dietary intake, median (IQR) | 26 (18–33) | 50 (44–55) | 74 (67–82) | 121 (104–153) | |
| Person-years | 179,140 | 181,424 | 182,575 | 181,670 | |
| Number of cases | 13 | 28 | 26 | 27 | |
| IR per 100,000 person-years | 7.3 | 15.4 | 14.2 | 14.9 | |
| Model 1 HR (95% CI) | Ref | 2.06 (1.07–3.98) | 1.81 (0.93–3.53) | 1.75 (0.90–3.41) | 0.23 |
| Model 2 HR (95% CI) | Ref | 2.08 (1.07–4.04) | 1.84 (0.93–3.62) | 1.79 (0.91–3.54) | 0.21 |
| Green leafy vegetables | |||||
| Dietary intake, median (IQR) | 12 (8-15) | 24 (21–27) | 39 (34–44) | 70 (58–91) | |
| Person-years | 175,753 | 180,709 | 183,145 | 185,202 | |
| Number of cases | 16 | 18 | 32 | 28 | |
| IR per 100,000 person-years | 9.1 | 10.0 | 17.5 | 15.1 | |
| Model 1 HR (95% CI) | Ref | 1.07 (0.54–2.11) | 1.79 (0.98–3.29) | 1.46 (0.78–2.73) | 0.11 |
| Model 2 HR (95% CI) | Ref | 1.07 (0.54-2.11) | 1.81 (0.98–3.35) | 1.47 (0.78–2.79) | 0.11 |
| Citrus fruits | |||||
| Dietary intake, median (IQR) | 20 (9-31) | 62 (52–71) | 105 (92–120) | 204 (165–278) | |
| Person-years | 182,907 | 184,835 | 181,630 | 175,439 | |
| Number of cases | 17 | 26 | 25 | 26 | |
| IR per 100,000 person-years | 9.3 | 14.1 | 13.8 | 14.8 | |
| Model 1 HR (95% CI) | Ref | 1.47 (0.79–2.72) | 1.34 (0.72–2.51) | 1.39 (0.74–2.61) | 0.43 |
| Model 2 HR (95% CI) | Ref | 1.45 (0.78–2.70) | 1.33 (0.71–2.51) | 1.38 (0.73–2.60) | 0.44 |
CI confidence interval, HR hazard ratio, IR incidence rate, IQR interquartile range, Ref reference.
Dietary intake was adjusted for total energy intake using the residual method (sex-specific), categorised into quartiles, and used in Cox proportional hazards regression model with the lowest category as the reference. Model 1: Cox proportional hazards regression models adjusted for age (continuous) and study area. Model 2 was further adjusted for smoking status (never smoker, ever smoker, or unknown); duration of smoking (continuous); the number of cigarettes per day (continuous); body mass index (30 kg/m2), history of diabetes mellitus (yes/no), family history of any cancers (yes/no), Alcohol intake (1 day/week and 1 day/week and >150 g/week), coffee intake (0, 300 ml/day), physical activity (quintile of metabolic equivalents), fish intake (quartile of energy-adjusted fish intake), red meat intake (quartile of energy-adjusted red meat intake) and supplement intake (yes/no).