Table 1.
Population characteristics according to case-control status
| PD cases, n (%) | Controls, n (%) | p | |
|---|---|---|---|
| All | 786 | 1537 | |
| Year of Birth | 0.04 | ||
| 1925–1929 | 281 (35.8) | 603 (39.2) | |
| 1930–1934 | 262 (33.3) | 544 (35.4) | |
| 1935–1939 | 159 (20.2) | 253 (16.5) | |
| 1940- | 84 (10.7) | 137 (8.9) | |
| Men | 600 (76.3) | 1211 (78.8) | 0.18 |
| Smoking | <.0001 | ||
| Never | 366 (46.6) | 537 (34.9) | |
| Former | 385 (49.0) | 893 (58.1) | |
| Current | 24 (3.1) | 91 (5.9) | |
| Missing | 11(1.4) | 16(1.0) | |
| Caffeine intake (mg/day) | 295.2 ± 335.2 | 361.3 ± 361.5 | <.0001 |
| Family History | <.0001 | ||
| Yes | 111 (14.1) | 84 (5.5) | <.0001 |
| No | 668 (85.0) | 1318 (85.8) | |
| Missing | 7 (0.9) | 135 (8.8) | |
| ApoE | 0.32 | ||
| ε22 | 6 (0.8) | 12 (0.8) | |
| ε23 | 100 (12.7) | 198 (12.9) | |
| ε33 | 522 (66.4) | 952 (61.9) | |
| ε34 | 133 (16.9) | 316 (20.6) | |
| ε44 | 11 (1.4) | 25 (1.6) | |
| ε24 | 14 (1.8) | 34 (2.2) | |
| Dementia | |||
| Yes | 131 (16.7) | ||
| No | 589 (74.9) | ||
| Missing | 66 (8.4) | ||
| Year of diagnosis | |||
| Before 2000 | 360 (45.8) | ||
| 2000 and after | 426 (54.2) |
Means were compared with t-tests and proportions were compared with chi-square tests.