Table 1.
Selected baseline characteristics and follow‐up information of cases and matched controls
| Characteristic | No.(%) of patients** | |||
|---|---|---|---|---|
| Cases | Controls (n = 224 643) | |||
| Estrogen‐only (n = 17 606) | Combined HRT (n = 87 593) | Total (n = 105 199) | ||
| Death at follow‐up | 1110 (6.3) | 5219 (6.0) | 6329 (6.0) | 15 422 (7.0) |
| Transferred out | 5078 (28.8) | 24 526 (27.9) | 29 604 (28.1) | 61 023 (27.2) |
| Mean follow‐up years (± SD) | 13.7 (7.1) | 14.0 (6.7) | 13.5 (6.8) | 13.2 (7.0) |
| Age group at first HRT | ||||
| 46–50 | 5035 (28.6) | 37 219 (42.5) | 42 254 (40.2) | 87 108 (38.8) |
| 51–55 | 6011 (34.1) | 30 654 (35.0) | 36 665 (34.9) | 72 486 (32.3) |
| 56–60 | 4069 (23.1) | 13 286 (15.2) | 17 355 (16.5) | 40 674 (18.1) |
| 61–65 | 2491 (14.1) | 6434 (7.30) | 8925 (8.5) | 24 375 (10.9) |
| Birth cohort | ||||
| 1921–1930 | 573 (3.3) | 1361 (1.6) | 1934 (1.8) | 5565 (2.5) |
| 1931–1940 | 5450 (31.0) | 18 940 (21.6) | 24 390 (23.2) | 55 047 (24.5) |
| 1941–1950 | 8438 (47.8) | 44 453 (50.7) | 52 891 (50.3) | 96 142 (42.8) |
| 1951–1960 | 3145 (17.9) | 22 839 (26.1) | 25 984 (24.7) | 67 889 (30.2) |
| Hypertension | ||||
| No* | 10 017 (56.9) | 55 266 (63.1) | 65 283 (62.1) | 134 337 (59.8) |
| Treated* | 4419 (25.1) | 18 657 (21.3) | 23 076 (22.0) | 49 421 (22.0) |
| Untreated* | 3170 (18.0) | 13 670 (15.6) | 16 840 (16.0) | 40 885 (18.2) |
| Uterine/ovarian status | ||||
| Intact | 6779 (38.5) | 78 214 (89.3) | 84 993 (80.8) | 203 625 (90.6) |
| Hysterectomy with oophorectomy*** | 9945 (56.5) | 1067 (1.2) | 11 012 (10.5) | 6502 (2.9) |
| Oophorectomy only | 882 (5.0) | 8312 (9.5) | 9194 (8.7) | 14 516 (6.5) |
| PAD/PVD | 1348 (7.7) | 7498 (8.6) | 8846 (8.4) | 17 340 (7.7) |
| Diabetes type 2 | 317 (1.8) | 1233 (1.4) | 1550 (1.5) | 5089 (2.3) |
| CHD | 336 (1.9) | 1033 (1.2) | 1369 (1.3) | 3130 (1.4) |
| Osteoporosis | 352 (2.0) | 2101 (2.4) | 2453 (2.3) | 4215 (1.9) |
| Hypercholesterolaemia | 254 (1.4) | 972 (1.1) | 1226 (1.2) | 2605 (1.2) |
| Body mass index | ||||
| Healthy weight/overweight* | 13 109 (74.5) | 69 023 (78.8) | 82 132 (78.1) | 161 294 (71.8) |
| Obese* | 4497 (25.5) | 18 570 (21.2) | 23 067 (21.9) | 63 349 (28.2) |
| Smoking status | ||||
| Non* | 10 966 (62.3) | 50 716 (57.9) | 61 682 (58.6) | 141 301 (62.9) |
| Ex* | 3187 (18.1) | 15 854 (18.1) | 19 041 (18.1) | 35 269 (15.7) |
| Current* | 3468 (19.7) | 21 022 (24.0) | 24 490 (23.3) | 48 298 (21.5) |
| Deprivation status | ||||
| Low* | 9648 (54.8) | 47 738 (54.5) | 57 386 (54.5) | 117 488 (52.3) |
| Medium* | 3662 (20.8) | 17 957 (20.5) | 21 616(20.5) | 46 950 (20.9) |
| High* | 4296 (24.4) | 21 811 (24.9) | 26 107 (24.8) | 60 204 (26.8) |
*
The reported prevalence of variables with missing values are the mean of ten imputed datasets. Due to missingness in systolic and diastolic blood pressure, missing values were generated in hypertension category.
**
All values are reported as n (%) except the mean follow‐up time.
***
Hysterectomy and at least one ovary removed.