Table 2. Hazard ratios (95% confidence intervals) for lung cancer incidence by daily coffee consumption.
| Coffee intake | P-trend | P-interaction | |||||
| No Coffee | <1 Cup/day | 1–2 Cups/day | 3–4 Cups/day | ≥5 Cups/day | |||
| Lung cancer (all) | |||||||
| Men | 0.331 | ||||||
| Number of cases | 403 | 370 | 296 | 109 | 49 | — | — |
| Age, area | 1.00 | 1.07 (0.93–1.23) | 1.27 (1.09–1.48) | 1.54 (1.24–1.91) | 1.88 (1.39–2.54) | <0.001 | — |
| Age, area, smoking | 1.00 | 0.95 (0.82–1.10) | 1.05 (0.89–1.23) | 1.02 (0.82–1.28) | 1.14 (0.83–1.55) | 0.405 | — |
| Multivariate-adjusted | 1.00 | 1.03 (0.88–1.22) | 1.11 (0.93–1.22) | 1.05 (0.82–1.34) | 1.16 (0.82–1.63) | 0.285 | — |
| Women | 0.169 | ||||||
| Number of cases | 163 | 139 | 103 | 23 | 13 | — | — |
| Age, area | 1.00 | 1.08 (0.86–1.36) | 1.00 (0.77–1.30) | 1.08 (0.69–1.70) | 2.06 (1.16–3.67) | 0.253 | — |
| Age, area, smoking | 1.00 | 1.08 (0.86–1.36) | 0.95 (0.73–1.24) | 0.90 (0.56–1.43) | 1.55 (0.86–2.79) | 0.839 | — |
| Multivariate-adjusted | 1.00 | 1.06 (0.82–1.36) | 0.94 (0.70–1.25) | 0.90 (0.55–1.48) | 1.49 (0.79–2.83) | 0.942 | — |
| Adenocarcinoma | |||||||
| Number of cases | 266 | 216 | 176 | 46 | 25 | — | — |
| Age, gender, area | 1.00 | 0.97 (0.81–1.16) | 1.10 (0.90–1.33) | 1.06 (0.77–1.46) | 1.66 (1.09–2.51) | 0.087 | — |
| Age, gender, area, smoking | 1.00 | 0.91 (0.76–1.09) | 0.97 (0.80–1.19) | 0.83 (0.59–1.16) | 1.21 (0.79–1.86) | 0.829 | — |
| Multivariate-adjusted | 1.00 | 0.95 (0.78–1.16) | 1.01 (0.81–1.26) | 0.80 (0.56–1.16) | 1.13 (0.70–1.83) | 0.778 | — |
| Squamous cell carcinoma | |||||||
| Number of cases | 107 | 106 | 76 | 30 | 16 | — | — |
| Age, gender, area | 1.00 | 1.20 (0.91–1.57) | 1.31 (0.97–1.77) | 1.80 (1.19–2.73) | 2.55 (1.50–4.35) | <0.001 | — |
| Age, gender, area, smoking | 1.00 | 1.06 (0.80–1.40) | 1.06 (0.78–1.45) | 1.10 (0.71–1.70) | 1.45 (0.84–2.49) | 0.303 | — |
| Multivariate-adjusted | 1.00 | 1.14 (0.83–1.55) | 1.10 (0.78–1.55) | 1.04 (0.63–1.69) | 1.24 (0.66–2.32) | 0.578 | — |
| Small cell carcinoma | |||||||
| Number of cases | 28 | 61 | 37 | 21 | 9 | — | — |
| Age, gender, area | 1.00 | 2.60 (1.66–4.08) | 2.28 (1.38–3.77) | 4.50 (2.51–8.06) | 5.39 (2.51–11.58) | <0.001 | — |
| Age, gender, area, smoking | 1.00 | 2.47 (1.56–3.93) | 1.88 (1.12–3.16) | 2.83 (1.54–5.17) | 2.62 (1.16–5.90) | 0.003 | — |
| Multivariate-adjusted | 1.00 | 2.51 (1.47–4.30) | 2.35 (1.33–4.17) | 3.48 (1.79–6.73) | 3.52 (1.49–8.28) | <0.001 | — |
| Other | |||||||
| Number of cases | 165 | 126 | 110 | 35 | 12 | — | — |
| Age, gender, area | 1.00 | 0.93 (0.74–1.17) | 1.17 (0.92–1.51) | 1.33 (0.92–1.94) | 1.27 (0.70–2.29) | 0.072 | — |
| Age, gender, area, smoking | 1.00 | 0.87 (0.68–1.10) | 1.00 (0.77–1.29) | 0.94 (0.64–1.38) | 0.83 (0.46–1.38) | 0.707 | — |
| Multivariate-adjusted | 1.00 | 0.94 (0.72–1.23) | 1.00 (0.75–1.35) | 0.99 (0.65–1.50) | 1.02 (0.55–1.88) | 0.958 | — |
Multivariate analyses were adjusted for the following factors at baseline: age (continuous); gender; PHC area; body-mass index (<18.5, 18.5–24.9, 25.0–29.9, and ≥30 kg/m2); smoking status (never, former: <10, 10–19, and ≥20 years of smoking cessation, current: 1–19, 20–29, 30–39, 40–49, 50–59, ≥60 pack-years); physical activity (almost never, <3 days/month, 1–2 days/week, 3–4 days/week, and almost everyday); alcohol consumption (never/former, <1 time/week, <23, 23–45, 46–68, 69–91, and >92 g of ethanol/day); consumption of green tea, Chinese tea, and black tea (almost never, <1 time/week, and >1 cup/day); energy-adjusted intake of fruit, vegetables, and isoflavone (continuous).