Table 5.
Hazard ratios (HRs) and 95% confidence intervals (CIs) of bladder cancer in relation to consumption of coffee, green tea, and caffeine in men by smoking status
| Category of intake | Coffee | ||||
|---|---|---|---|---|---|
| Almost none | 1–4 times/week | ≥1 cups/day | P trend | P interaction | |
| Never smoker | |||||
| Number of cases | 6 | 9 | 11 | ||
| HR † (95% CI) | 1.00 (reference) | 1.89 (0.67–5.32) | 2.48 (0.88–7.05) | 0.09 | 0.25 |
| Former smoker | |||||
| Number of cases | 13 | 13 | 16 | ||
| HR † (95% CI) | 1.00 (reference) | 1.25 (0.58–2.71) | 2.09 (0.96–4.54) | 0.07 | |
| Never/Former smoker | |||||
| Number of cases | 19 | 22 | 27 | ||
| HR † (95% CI) | 1.00 (reference) | 1.47 (0.79–2.72) | 2.24 (1.21–4.16) | 0.01 | |
| Current smoker | |||||
| Number of cases | 29 | 30 | 33 | ||
| HR † (95% CI) | 1.00 (reference) | 1.11 (0.65–1.90) | 1.13 (0.65–1.97) | 0.67 | |
| Category of intake | Green tea | ||||
|---|---|---|---|---|---|
| <3 cups/day | 3–4 cups/day | ≥5 cups/day | P trend | P interaction | |
| Never smoker | |||||
| Number of cases | 13 | 6 | 7 | ||
| HR ‡ (95% CI) | 1.00 (reference) | 0.81 (0.30–2.19) | 0.85 (0.31–2.32) | 0.72 | 0.42 |
| Former smoker | |||||
| Number of cases | 14 | 12 | 16 | ||
| HR ‡ (95% CI) | 1.00 (reference) | 1.17 (0.53–2.56) | 1.40 (0.67–2.95) | 0.38 | |
| Never/Former smoker | |||||
| Number of cases | 27 | 18 | 23 | ||
| HR ‡ (95% CI) | 1.00 (reference) | 0.98 (0.53–1.79) | 1.14 (0.63–2.04) | 0.68 | |
| Current smoker | |||||
| Number of cases | 14 | 18 | 30 | ||
| HR ‡ (95% CI) | 1.00 (reference) | 0.44 (0.24–0.80) | 0.62 (0.37–1.04) | 0.05 | |
| Category of intake | Caffeine (median, mg/day) | ||||
|---|---|---|---|---|---|
| Lowest (0.06) | Middle (0.15) | Highest (0.28) | P trend | P interaction | |
| Never smoker | |||||
| Number of cases | 12 | 6 | 8 | ||
| HR § (95% CI) | 1.00 (reference) | 0.95 (0.35–2.58) | 1.66 (0.66–4.20) | 0.33 | 0.04 |
| Former smoker | |||||
| Number of cases | 13 | 13 | 16 | ||
| HR § (95% CI) | 1.00 (reference) | 1.19 (0.55–2.59) | 2.30 (1.08–4.87) | 0.03 | |
| Never/Former smoker | |||||
| Number of cases | 25 | 29 | 24 | ||
| HR § (95% CI) | 1.00 (reference) | 1.09 (0.59–2.00) | 2.05 (1.15–3.66) | 0.02 | |
| Current smoker | |||||
| Number of cases | 38 | 30 | 24 | ||
| HR § (95% CI) | 1.00 (reference) | 0.87 (0.53–1.44) | 0.72 (0.41–1.27) | 0.25 | |
Adjusted for age (continuous), area (10 public health center areas), smoking status (never, former [<10, 10–19, ≥20 years since cessation of smoking], current [<20, 20–29, 30–39, 40–49, ≥50 pack‐years]), alcohol drinking (non‐ or occasional drinkers, 1–150, = 150 g/week), and green tea (<1, 1–2, 3–4, ≥5 cups/day).
Adjusted for age (continuous), area (10 public health center areas), smoking status (never, former [<10, 10–19, ≥20 years since cessation of smoking], current [<20, 20–29, 30–39, 40–49, ≥50 pack‐years]), alcohol drinking (non‐ or occasional drinkers, 1–150, ≥150 g/week), and coffee (almost none, 1–4 times/week, 1–2, ≥3 cups/day).
Adjusted for age (continuous), area (10 public health center areas), smoking status (never, former [<10, 10–19, ≥20 years since cessation of smoking], current [<20, 20–29, 30–39, 40–49, ≥50 pack‐years]), and alcohol drinking (non‐ or occasional drinkers, 1–150, ≥150 g/week).