Table 1:
Selected baseline characteristics [medians (25th–75th percentile) or proportions (N, %)] by categories of hair greyness and hair dye use in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study (1985–2012)
| No grey hair (N=5,163) | Less grey hair (≤25%) (N=13,841) | More grey hair (>25%−100%) (N=9,150) | Bald (N=566) | Dyed hair (N=75) | Non-hair dye usersa (N=28,720) | |
|---|---|---|---|---|---|---|
| Characteristics | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD | Mean ± SD |
| Age (years) | 54.99 ± 4.37 | 56.59 ± 4.79 | 59.20 ± 5.08 | 59.13 ± 5.29 | 58.95 ± 4.90 | 57.19 ± 5.06 |
| Height (cm) | 173.6 ± 6.4 | 173.7 ± 6.1 | 173.5 ± 6.2 | 172.4 ± 6.0 | 174.3 ± 5.8 | 173.6 ± 6.2 |
| Weight (kg) | 78.3 ± 13.2 | 79.4 ± 12.8 | 79.9 ± 12.9 | 78.2 ± 12.3 | 79.7 ± 11.4 | 79.3 ± 12.9 |
| Body mass index (kg/m2)b | 25.9 ± 3.9 | 26.3 ± 3.8 | 26.5 ± 3.8 | 26.3 ± 3.7 | 26.2 ± 3.1 | 26.3 ± 3.8 |
| Cigarettes smoked per day | 21.4 ± 9.0 | 20.6 ± 8.9 | 19.7 ± 8.6 | 20.3 ± 8.4 | 18.6 ± 8.2 | 20.4 ± 8.8 |
| Years of smoking | 34.0 ± 7.8 | 35.3 ± 8.4 | 37.8 ± 8.5 | 37.5 ± 9.1 | 36.4 ± 10.2 | 35.9 ± 8.5 |
| Serum biomarkers | ||||||
| Total cholesterol (mmol/L) | 6.24 ± 1.18 | 6.25 ± 1.16 | 6.21 ± 1.17 | 6.21 ± 1.16 | 6.11 ± 1.20 | 6.23 ± 1.17 |
| HDL cholesterol (mmol/L) | 1.22 ± 0.33 | 1.20 ± 0.32 | 1.18 ± 0.31 | 1.19 ± 0.33 | 1.20 ± 0.38 | 1.20 ± 0.32 |
| N (%) | N (%) | N (%) | N (%) | N (%) | N (%) | |
| Trial α-tocopherol supplementation | 2,569 (49.8) | 6,885 (49.7) | 4,628 (50.6) | 281 (49.7) | 35 (46.7) | 14,363 (50.0) |
| Trial β-carotene supplementation | 2,544 (49.3) | 6,911 (49.9) | 4,608 (50.4) | 285 (50.4) | 37 (49.3) | 14,348 (50.0) |
| Education/training above 8th grade | 3445 (66.8) | 9198 (66.5) | 6016 (65.8) | 322 (56.9) | 56 (74.7) | 18,984 (66.1) |
| Physically active | 1,329 (25.8) | 3,061 (22.1) | 1,521 (16.6) | 81 (14.3) | 12 (16.0) | 5.992 (20.9) |
| Family history of prostate cancer | 99 (3.0) | 291 (3.2) | 207 (3.6) | 13 (3.7) | 2 (4.6) | 610 (3.3) |
a
Weight (kg)/height (m)2
b
This column combines ‘no grey hair’, ‘Less grey hair’, ‘More grey hair’ and ‘bald’.
Abbreviations: SD: standard deviation; HDL: high-density lipoprotein