Table 1.
Distribution of selected characteristics among cases and controls, overall and by HPV serology
| All | High-risk HPVa seropositive | High-risk HPV seronegative | |||||
|---|---|---|---|---|---|---|---|
| Characteristic | Cases (n=959) | Controls (n=1208) | P value | Cases (n=525) | P valueb | Cases (n=296) | P value |
| Sex | |||||||
| Female | 258(26.9) | 323(26.7) | 0.93c | 121 (23.0) | 0.11 | 86 (29.0) | 0.42c |
| Male | 701(73.0) | 885(73.2) | 404 (76.9) | 210(70.9) | |||
| Race/Ethnicity | |||||||
| Caucasian | 871(90.8) | 1,090(90.2) | 0.59c | 487 (92.7) | 0.05 | 272(91.8) | 0.30c |
| Non-Caucasian | 87(9.0) | 118(9.7) | 38 (7.2) | 23 (7.7) | |||
| Age | |||||||
| 0-40 | 31(3.2) | 38(3.1) | 0.02b | 11 (2.0) | 0.001 | 16(5.4) | 0.45b |
| 40-50 | 131(13.6) | 133(11.0) | 78(14.8) | 38(12.8) | |||
| 50-60 | 324(33.7) | 384(31.7) | 192 (36.5) | 89(30.0) | |||
| 60-70 | 294(30.6) | 389(32.2) | 167 (31.8) | 87(29.3) | |||
| ≥70 | 179(18.6) | 264(21.8) | 77(14.6) | 66(22.2) | |||
| Education | |||||||
| High School | 401(41.8) | 340(28.1) | <.0001c | 194 (36.9) | 0.001 | 138(46.6) | <.0001c |
| College | 378(39.4) | 551(45.6) | 209 (39.8) | 114(38.5) | |||
| Professional School | 167(17.4) | 288(23.8) | 111 (21.1) | 43(14.5) | |||
| BMI | |||||||
| 18.5-25 | 325(33.8) | 360(29..8) | <0.01c | 154 (29.3) | 0.22 | 119 (40.2) | <0.001c |
| 25-30 | 421(43.8) | 504(41.7) | 240 (45.7) | 124 (41.8) | |||
| ≥30 | 213(22.2) | 344(28.4) | 131 (24.9) | 53(17.9) | |||
| Alcohol | |||||||
| First quartile | 173(18.0) | 302(25.0) | <.0001b | 98 (18.6) | <.0001 | 51 (17.2) | <.0001b |
| Second quartile | 152(15.8) | 300(24.8) | 86 (16.3) | 43 (14.5) | |||
| Third quartile | 189(19.7) | 302(25.0) | 121 (23.0) | 46 (15.5) | |||
| Forth quartile | 442(46.0) | 301(24.9) | 219 (41.7) | 154(52.0) | |||
| Smoking Statusd | |||||||
| Never | 236(24.6) | 486(40.2) | <.0001c | 158 (30.0) | <.0001 | 52 (17.5) | <.0001c |
| Former | 596(62.1) | 557(46.1) | 317 (60.3) | 190 (64.1) | |||
| Current | 116(12.0) | 152(12.5) | 42(8..0) | 52 (17.5) | |||
| Smoking | |||||||
| Never | 236(24.6) | 486(40.2) | <.0001b | 158 (30.0) | <0.001 | 52 (17.5) | <.0001b |
| Moderatee | 221(23.0) | 293(24.2) | 138(26.2) | 52 (17.5) | |||
| Heavyf | 502(52.3) | 429(35.5) | 229(43.6) | 192 (64.8) | |||
| Tumor Site | |||||||
| Laryngeal | 153(15.9) | 67 (12.7) | 64(21.6) | ||||
| Oral cavity | 353(36.8) | 149(28.3) | 144 (48.6) | ||||
| Pharyngeal | 440(45.8) | 305(58.0) | 84 (28.3) | ||||
| Tumor Stage | |||||||
| I | 131(13.6) | 49 (9.3) | 64 (21.6) | ||||
| II | 124(12.9) | 53(10.0) | 47(15.8) | ||||
| III | 153(15.9) | 86(16.3) | 44(14.8) | ||||
| IV | 485(50.5) | 319(60.7) | 115(38.8) | ||||
a
High-risk HPV include HPV16, 18, 31, 33, 45, 52, 58.
b
Spearman test for continuous variables and chi-square test for categorical variables.
c
Chi-square test for categorical variables.
d
Former (not smoking at time of interview) and current smokers (smoking at time of interview) reported having ever smoked 100 cigarettes or more (five packs) in their lifetime; if they had not, they were considered to be never smokers.
e
Moderate smoker was defined as those who smoke but less than 20 pack years.
f
Heavy smoker is defined as those who smoke more than 20 pack years.