Table 1. Patient demographics for cases and controls.
| Median age (IQR) (diagnosis/index date) | 29.8 (22.9-38.3) | 29.8 (22.9-38.3) | 33.2 (26.4-40.1) | 33.2 (26.4-40.1) |
| Townsend | ||||
| 1 | 412 (18.5) | 2670 (20.1) | 567 (21.0) | 3385 (21.1) |
| 2 | 382 (17.1) | 2353 (17.7) | 526 (19.5) | 2934 (18.3) |
| 3 | 401 (17.8) | 2387 (18.0) | 481 (17.8) | 2981 (18.6) |
| 4 | 354 (15.9) | 2096 (15.8) | 394 (14.6) | 2496 (15.5) |
| 5 | 268 (12.0) | 1522 (11.5) | 251 (9.3) | 1704 (10.6) |
| Missing | 414 (18.6) | 2251 (17.0) | 482 (17.9) | 2561 (16.0) |
| Weight | ||||
| Median BMI (IQR) | 23.6 (21.0-27.6) | 23.8 (21.2-27.9) | 23.1 (20.8-26.4) | 23.9 (21.3-28.0) |
| Normal weight (BMI 18-25) | 1042 (46.7) | 5532 (41.7) | 1436 (53.2) | 7119 (44.3) |
| Overweight (BMI 25-30) | 428 (19.2) | 2252 (17.0) | 476 (17.6) | 3050 (19.0) |
| Obese (BMI >30) | 310 (13.9) | 1874 (14.1) | 294 (10.9) | 2313 (14.4) |
| Underweight (BMI <17) | 81 (3.6) | 358 (2.7) | 91 (3.4) | 380 (2.4) |
| Missing | 370 (16.6) | 3263 (24.6) | 404 (15.0) | 3199 (19.9) |
| Smoking | ||||
| Non-smoker | 968 (43.4) | 6480 (48.8) | 1384 (51.2) | 8078 (50.3) |
| Ex-smoker | 238 (10.7) | 1112 (8.4) | 395 (14.6) | 1505 (9.4) |
| Smoker | 690 (30.9) | 2980 (22.4) | 563 (20.8) | 3552 (22.1) |
| Missing | 335 (15.0) | 2707 (20.4) | 359 (13.3) | 2926 (18.2) |
| Polycystic ovarian syndrome | 56 (2.5) | 328 (2.5) | 58 (2.2) | 464 (2.9) |
| Endometriosis | 37 (1.7) | 148 (1.1) | 35 (1.3) | 215 (1.3) |
| Pregnancy | 630 (28.2) | 3553 (26.8) | 867 (32.1) | 4606 (28.7) |
| Acne | 341 (15.3) | 2333 (17.6) | 491 (18.2) | 2710 (16.9) |
Abbreviation: BMI, body mass index.