Table 1. Selected characteristics of study subjects by case-control status.
| Control Subjects | Biliary Stones | Biliary Tract Cancer | |||||
|---|---|---|---|---|---|---|---|
| Selected Characteristics | All1 | Without cholecystectomy2 | Without stones3 | All stones4 | Gallbladder | Bile Duct | Ampulla of Vater |
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |
| All subjects | 959 (100.0) | 902 (100.0) | 735 (100.0) | 1037 (100.0) | 368 (100.0) | 191 (100.0) | 68 (100.0) |
| Gender | |||||||
| Male | 373 (38.9) | 357 (39.6) | 313 (42.6) | 390 (37.6)* | 99 (26.9)*** | 99 (51.8)*** | 37 (54.4)** |
| Female | 586 (61.1) | 545 (60.4) | 422 (57.4) | 647 (62.4) | 269 (73.1) | 92 (48.2) | 31 (45.6) |
| Age at interview | |||||||
| 34-54 | 128 (13.3) | 126 (14.0) | 115 (15.6) | 307 (29.6)*** | 49 (13.3) | 30 (15.7) | 6 (8.8) |
| 55-64 | 269 (28.1) | 259 (28.7) | 207 (28.2) | 298 (28.7) | 96 (26.1) | 47 (24.6) | 20 (29.4) |
| 65-75 | 562 (58.6) | 517 (57.3) | 413 (56.2) | 432 (41.7) | 223 (60.6) | 114 (59.7) | 42 (61.8) |
| Education | |||||||
| Elementary | 396 (41.3) | 365 (40.5) | 285 (38.8) | 317 (30.6)** | 198 (53.8)*** | 86 (45.0) | 29 (42.6) |
| High school | 423 (44.1) | 405 (44.9) | 336 (45.7) | 537 (51.8) | 129 (35.1) | 74 (38.7) | 31 (45.6) |
| Above high school | 140 (14.6) | 132 (14.6) | 114 (15.5) | 183 (17.6) | 41 (11.1) | 31 (16.2) | 8 (11.8) |
| Marital status | |||||||
| Married | 751 (78.3) | 703 (78.0) | 584 (79.5) | 884 (85.2)** | 284 (77.2) | 161 (84.3) | 55 (80.9) |
| Divorced, widowed | 196 (20.4) | 187 (20.7) | 143 (19.4) | 143 (13.8) | 81 (22.0) | 28 (14.7) | 13 (19.1) |
| Single | 12 (1.3) | 12 (1.3) | 8 (1.1) | 10 (1.0) | 3 (0.8) | 2 (1.0) | 0 (0.0) |
| Ever smoked cigarettes 5 | |||||||
| No | 674 (70.3) | 633 (70.2) | 508 (69.1) | 754 (72.7) | 278 (75.8) | 115 (60.2) | 38 (55.9) |
| Yes | 285 (29.7) | 269 (29.8) | 227 (30.9) | 283 (27.3) | 89 (24.2)* | 76 (39.8)* | 30 (44.1)* |
| Ever drank alcohol | |||||||
| No | 760 (79.2) | 715 (79.4) | 568 (77.4) | 869 (83.9)*** | 316 (85.9)** | 141 (73.8) | 53 (77.9) |
| Yes | 198 (20.6) | 186 (20.6) | 166 (22.6) | 167 (16.1) | 52 (14.1) | 50 (26.2) | 15 (22.1) |
| Body mass index (kg/m2) | |||||||
| <18.5 | 84 (8.7) | 83 (9.2) | 70 (9.5) | 51 (4.9)*** | 20 (5.4)*** | 11 (5.8) | 1 (1.5) |
| 18.5-22.9 | 400 (41.7) | 386 (42.8) | 336 (45.7) | 345 (33.3) | 130 (35.3) | 85 (44.5) | 29 (42.6) |
| 23.0-24.9 | 198 (20.6) | 185 (20.5) | 147 (20.0) | 263 (25.4) | 73 (19.8) | 49 (25.7) | 15 (22.1) |
| ≥25 | 277 (28.9) | 248 (27.5) | 182 (24.8) | 378 (36.5) | 145 (39.4) | 46 (24.1) | 23 (33.8) |
| Diabetes | |||||||
| No | 881 (91.9) | 834 (92.5) | 688 (93.6) | 925 (89.3)*** | 316 (86.1)*** | 171 (89.5) | 63 (92.6) |
| Yes | 78 (8.1) | 68 (7.5) | 47 (6.4) | 111 (10.7) | 51 (13.9) | 20 (10.5) | 5 (7.4) |
| Hypertension | |||||||
| No | 553 (57.7) | 526 (58.3) | 441 (60.0) | 695 (67.0)** | 230 (62.5) | 130 (68.1)** | 48 (70.6)* |
| Yes | 406 (42.3) | 376 (41.7) | 294 (40.0) | 342 (33.0) | 138 (37.5) | 61 (31.9) | 20 (29.4) |
| Gallstones | |||||||
| No | 735 (76.6) | 735 (81.5) | 735 (100.0) | 0 (0.0) | 60 (16.3)*** | 64 (33.5)*** | 32 (47.1)*** |
| Yes | 224 (23.4) | 167 (18.5) | 0 (0.0) | 1037 (100.0) | 308 (83.7) | 127 (66.5) | 36 (52.9) |
| Family history of gallstones 6 | |||||||
| No | 868 (90.5) | 820 (90.9) | 667 (90.7) | 792 (76.4)*** | 297 (80.7)*** | 162 (84.8)* | 58 (85.3) |
| Yes | 91 (9.5) | 82 (9.1) | 68 (9.3) | 245 (23.6) | 71 (19.3) | 29 (15.2) | 10 (14.7) |
| Treated with cholecystectomy | 49 (5.1) | 43 (4.8) | 33 (4.8) | 0 (0.0) | 36 (9.8) | 11 (5.8) | 6 (8.8) |
| Family history of any cancer 6 | |||||||
| No | 620 (65.9) | 583 (65.7) | 486 (66.9) | 696 (68.2) | 266 (74.7)** | 120 (63.8) | 42 (61.8) |
| Yes | 321 (34.1) | 304 (34.3) | 240 (33.1) | 325 (31.8) | 90 (25.3) | 68 (36.2) | 26 (38.2) |
| Family history of biliary tract cancer 6 | |||||||
| No | 959 (100.0) | 902 (100.0) | 735 (100.0) | 1030 (99.3)** | 368 (100.0) | 189 (99.0) | 68 (100.0) |
| Yes | 0 (0.0) | 0 (0.0) | 0 (0.0) | 7 (0.7) | 0 (0.0) | 2 (1.0) | 0 (0.0) |
| Have at least one sibling | |||||||
| No | 48 (5.0) | 46 (5.1) | 34 (4.7) | 56 (5.4) | 26 (7.1) | 12 (6.3) | 5 (7.5) |
| Yes | 905 (95.0) | 851 (94.9) | 697 (95.3) | 973 (94.6) | 340 (92.9) | 177 (93.7) | 62 (92.5) |
| Have at least one offspring | |||||||
| No | 39 (4.1) | 37 (4.1) | 29 (4.0) | 47 (4.5) | 10 (2.7) | 10 (5.3) | 2 (2.9) |
| Yes | 918 (95.9) | 863 (95.9) | 704 (96.0) | 988 (95.5) | 358 (97.3) | 180 (94.7) | 66 (97.1) |
| Number siblings and offspring | |||||||
| < 5 | 212 (22.1) | 208 (23.1) | 179 (24.4) | 301 (29.0)* | 78 (21.2) | 43 (22.5) | 10 (14.7) |
| 5-7 | 398 (41.5) | 374 (41.5) | 297 (40.4) | 427 (41.2) | 146 (39.7) | 83 (43.5) | 30 (44.1) |
| 8-9 | 193 (20.1) | 182 (20.2) | 148 (20.1) | 186 (17.9) | 83 (22.6) | 38 (19.9) | 18 (26.5) |
| ≥ 10 | 156 (16.3) | 138 (15.3) | 111 (15.1) | 123 (11.9) | 61 (16.6) | 27 (14.1) | 10 (14.7) |
1
All population controls compared with bile duct and ampulla vater cancer cases
2
Population controls who did not have a cholesectomy compared with gallbadder cancer cases
3
Population controls without biliary stones compared to biliary stone cases
4
Includes gallstones and bile duct stones
5
Ever smoked cigarettes for at least 6 consecutive months
6
At least one affected first-degree relative, i.e. parent, sibling, offspring
*
p<0.05,
**
p<0.01,
***
p<0.001 for Fisher's exact test for difference between cases and controls