Table 1.
Demographic and exposure characteristics of thyroid cancer case and control subjects
| Variable | Controls (No. = 511) | DTC cases (No. = 303) | P* | PTC cases (No. = 273) | P* | |||
|---|---|---|---|---|---|---|---|---|
|
|
|
|||||||
| No. | (%) | No. | (%) | No. | (%) | |||
| Age, years | ||||||||
| ≤45 | 198 | (38.7) | 162 | (53.5) | <0.001 | 153 | (56.0) | <0.001 |
| > 45 | 313 | (61.3) | 141 | (46.5) | 120 | (44.0) | ||
| Sex | ||||||||
| Male | 245 | (47.9) | 103 | (34.0) | <0.001 | 89 | (32.6) | <0.001 |
| Female | 266 | (52.1) | 200 | (66.0) | 184 | (67.4) | ||
| Race/ethnicity | ||||||||
| Non-Hispanic white | 401 | (78.5) | 214 | (70.6) | 0.012 | 191 | (70.0) | 0.008 |
| Other | 110 | (21.5) | 89 | (29.4) | 82 | (30.0) | ||
| First-degree family history of cancer | ||||||||
| Yes | 257 | (51.4) | 151 | (50.0) | 0.701 | 133 | (48.9) | 0.506 |
| No | 243 | (48.6) | 151 | (50.0) | 139 | (51.1) | ||
| Smoking status | ||||||||
| Current | 99 | (19.6) | 29 | (9.6) | <0.001 | 28 | (10.3) | 0.002 |
| Former | 114 | (22.5) | 69 | (22.8) | 59 | (21.7) | ||
| Never | 293 | (57.9) | 204 | (67.6) | 185 | (68.0) | ||
| Alcohol drinking status | ||||||||
| Current | 171 | (33.8) | 95 | (31.4) | 0.112 | 89 | (32.7) | 0.107 |
| Former | 75 | (14.8) | 32 | (10.6) | 27 | (10.0) | ||
| Never | 260 | (51.4) | 175 | (58.0) | 156 | (57.3) | ||
| Radiation exposure | ||||||||
| No | 504 | (98.6) | 293 | (97.0) | 0.110 | 264 | (97.1) | 0.127 |
| Yes | 7 | (1.4) | 9 | (3.0) | 8 | (2.9) | ||
*
Chi-square test, compared to controls.
Abbreviations: DTC, differentiated thyroid carcinoma; PTC, papillary thyroid carcinoma.