Table 2.
Multivariable-adjusted hazard ratios and 95% confidence intervals of prostate cancer by quintile of serum α-tocopherol concentration at baseline, among 29,102 Finnish male smokers in the ATBC Study
| Serum measure | Events/Total person-years of follow-up | Prostate cancer incidence ratea | HR (95%CI)b |
|---|---|---|---|
| Baseline α-tocopherol, range, mg/L | |||
| All prostate cancer | |||
| Q1 ≤ 9.3 | 497/86 812 | 5.7 | 1.00 (Ref) |
| Q2 > 9.3 and ≤ 10.8 | 543/96 890 | 5.6 | 0.93 (0.82, 1.06) |
| Q3 > 10.8 and ≤ 12.2 | 569/95 589 | 6.0 | 0.99 (0.87, 1.12) |
| Q4 > 12.2 and ≤ 14.2 | 599/102 060 | 5.9 | 0.96 (0.84, 1.10) |
| Q5 > 14.2 | 516/98 227 | 5.3 | 0.87 (0.75, 1.02) |
| Ptrendc | 0.57 | ||
| Aggressive prostate cancerd | |||
| Q1 ≤ 9.3 | 223/83 247 | 2.7 | 1.00 (Ref) |
| Q2 > 9.3 and ≤ 10.8 | 307/93 895 | 3.3 | 1.12 (0.94, 1.34) |
| Q3 > 10.8 and ≤ 12.2 | 267/91 580 | 2.9 | 0.98 (0.81, 1.18) |
| Q4 > 12.2 and ≤ 14.2 | 317/98 341 | 3.2 | 1.04 (0.86, 1.26) |
| Q5 > 14.2 | 257/94 755 | 2.7 | 0.87 (0.70, 1.09) |
| Ptrend | 0.27 | ||
| Non-aggressive prostate cancer | |||
| Q1 ≤ 9.3 | 365/85 349 | 4.3 | 1.00 (Ref) |
| Q2 > 9.3 and ≤ 10.8 | 373/94 762 | 3.9 | 0.87 (0.75, 1.01) |
| Q3 > 10.8 and ≤ 12.2 | 420/93 797 | 4.5 | 0.99 (0.85, 1.15) |
| Q4 > 12.2 and ≤ 14.2 | 452/100 192 | 4.5 | 0.99 (0.85, 1.15) |
| Q5 > 14.2 | 383/96 651 | 4.0 | 0.89 (0.75, 1.06) |
| Ptrend | 0.57 | ||
Crude prostate cancer incidence rate per 1000 person-years; ATBC, Alpha-Tocopherol, Beta-Carotene Cancer Prevention.
Cox proportional hazards regression using person-years as the time metric to calculate hazard ratios and 95% confidence intervals of associations between measures of serum α-tocopherol (quintiles) and incidence of prostate cancer, and adjusted for age at randomization, body mass index, years of cigarette smoking, number of cigarettes smoked daily, serum total cholesterol concentration, and trial intervention group
Two-sided P-trend is based on the statistical significance of the coefficient of the quintile variable (median value within each quintile).
Aggressive prostate cancer was defined as TNM stage III or IV, AJCC, stage ≥3, or Gleason sum ≥8.
Abbreviations: HR, hazard ratio; 95% CI, 95 % confidence interval, Q, quintile; AJCC, American Joint Committee on Cancer;