Table 1.
Selected characteristics of study subjects.
| Cases (n = 1,916) | Controls (n = 1,985) | ||
|---|---|---|---|
| Age in years, mean ± std | 63.5 ± 6.8 | 64.8 ± 6. 9 | <0.0001 |
| Ancestry, n (%) | <0.0001 | ||
| African | 128 (6.7) | 86 (4.3) | |
| Asian | 24 (1.3) | 69 (3.5) | |
| European | 1,677 (87.5) | 1,683 (84.8) | |
| Other | 75 (3.9) | 133 (6.7) | |
| Don’t know | 12 (0.6) | 14 (0.7) | |
| First-degree family history of prostate cancer, n (%) | <0.0001 | ||
| No | 1,402 (73.2) | 1,730 (87.2) | |
| 196 (9.9) | |||
| Yes | 446 (23.3) | 59 (3.0) | |
| Don’t know | 68 (3.5) | ||
| Education, n (%) | 0.2522 | ||
| Elementary | 445 (23.2) | 426 (21.5) | |
| High School | 568 (29.6) | 575 (29.0) | |
| College | 313 (16.3) | 375 (18.9) | |
| University | 587 (30.6) | 607 (30.6) | |
| Don’t know | 3 (0.2) | 2 (0.1) | |
| Family income in CAN$, n (%) | 0.1453 | ||
| <20,000 | 222 (11.6) | 243 (12.2) | |
| 20,000–29,999 | 262 (13.7) | 251 (12.6) | |
| 30,000–49,999 | 444 (23.2) | 460 (23.2) | |
| 50,000–79,999 | 422 (22.0) | 410 (20.7) | |
| ≥80,000 | 424 (22.1) | 428 (21.6) | |
| Prefers not to respond/don’t know | 142 (7.4) | 193 (9.7) | |
| Body mass index 2 years ago in kg/m2, mean ± std | 26.8 ± 4.0 | 27.2 ± 4.4 | 0. 0019 |
| Physical activity, n (%) | 0.1701 | ||
| Not very active | 430 (22.4) | 485 (24.4) | |
| Moderately active | 521 (27.2) | 557 (28.1) | |
| Very active | 964 (50.4) | 943 (47.5) | |
| Smoking in cigarettes-years,a mean ± std | 610.4 ± 539.01 | 649.8 ± 546.78 | 0.0549 |
| Beer consumption in drink-years,b mean ± std | 56.2 ± 101.25 | 54.9 ± 100.51 | 0.7500 |
| History of type II diabetes, n (%) | <0.0001 | ||
| No | 1,684 (87.9) | 1,604 (80.8) | |
| Yes | 229 (12.0) | 393 (19.0) | |
| Don’t know | 3 (0.2) | 3 (0.2) | |
| Number of PSA tests in previous 5 yearsc, n (%) | <0.0001 | ||
| ≥5 | 982 (51.3) | 889 (44.7) | |
| 1–4 | 797 (41.6) | 657 (33.1) | |
| 0 | 6 (0.3) | 254 (12.8) | |
| Don’t know | 130 (6.8) | 185 (9.3) | |
| Respondent status, n (%) | 0.0242 | ||
| Self | 1867 (97.4) | 1909 (96.2) | |
| Daily dietary intakes, mean ± std | |||
| Vitamin C, mg (absolute amount) | 150.8 ± 80.1 | 145.7 ± 74.8 | 0.0400 |
| Vitamin C, mg (based on residual method) | 145.3 ± 75.7 | 142.9 ± 70.0 | 0.3041 |
| Vitamin E, mg | 6.7 ± 2.4 | 6.6 ± 2.5 | 0.3317 |
| Calcium, mg | 1026.4 ± 422.7 | 1000.3 ± 405.1 | 0.0493 |
| Selenium, μg | 143.9 ± 47.4 | 141.2 ± 48.1 | 0.0791 |
| Lycopene, μg | 8770.0 ± 7044.2 | 7826.9 ± 6274.5 | <0.0001 |
| Beta-carotene, μg | 4420.2 ± 2612.0 | 4334.7 ± 2820.6 | 0.3265 |
| Folates, μg | 472.1 ± 156.8 | 458.5 ± 157.1 | 0.0068 |
| Saturated fatty acids, g | 27.0 ± 11.6 | 26.0 ± 11.6 | 0.0053 |
| Polyunsaturated fatty acids, g | 14.1 ± 5.5 | 13.9 ± 5.5 | 0.2007 |
| Red meat, g | 132.7 ± 90.4 | 128.1 ± 93.0 | 0.1168 |
| Energy, kcal | 2243.9 ± 708.6 | 2172.5 ± 690.2 | 0.0015 |
| Regulard use of vitamin C supplement, n (%) | 196 (10.2) | 181 (9.1) | 0.4273 |
| Regulard use of multivitamin supplement, n (%) | 358 (18.7) | 392 (19.7) | 0.6904 |
aAmong ever smokers. bAmong subjects who reported ever consuming alcohol once a month for one year or more cPSA: prostate-specific antigen. dDefined as at least once a week.