Distributions of baseline characteristics among patients with cancer and cancer-free controls
| Characteristic | No. (%) of individuals | Standardized difference* | |
|---|---|---|---|
| Cancer-free controls n = 1 607 480 | Patients with cancer n = 803 740 | ||
| Age at diagnosis, yr | |||
| 18–39 | 75 689 (4.7) | 37 827 (4.7) | 0.00 |
| 40–49 | 129 643 (8.1) | 64 616 (8.0) | |
| 50–59 | 292 016 (18.2) | 146 033 (18.2) | |
| 60–69 | 431 711 (26.9) | 215 979 (26.9) | |
| ≥ 70 | 678 421 (42.2) | 339 285 (42.2) | |
| Sex | |||
| Female | 800 122 (49.8) | 400 061 (49.8) | 0.00 |
| Male | 807 358 (50.2) | 403 679 (50.2) | |
| Rurality† | |||
| Urban | 1 449 450 (90.2) | 721 830 (89.8) | 0.01 |
| Rural | 156 331 (9.7) | 81 369 (10.1) | |
| Deprivation quintile† | |||
| Q1 (least) | 320 027 (19.9) | 160 154 (19.9) | 0.00 |
| Q2 | 319 160 (19.9) | 160 118 (19.9) | |
| Q3 | 315 001 (19.6) | 158 534 (19.7) | |
| Q4 | 319 604 (19.9) | 159 311 (19.8) | |
| Q5 (most) | 320 046 (19.9) | 160 005 (19.9) | |
| Elixhauser Comorbidity Index score | |||
| 0–3 (low) | 1 500 636 (93.4) | 727 865 (90.6) | 0.10 |
| ≥ 4 (high) | 106 844 (6.6) | 75 875 (9.4) | |
| Prior usage of mental health services | |||
| No use of mental health services | 991 004 (61.6) | 486 962 (60.6) | 0.02 |
| Inpatient | 13 503 (0.8) | 6583 (0.8) | |
| Outpatient | 29 524 (1.8) | 14 246 (1.8) | |
| Mental health services use | 573 449 (35.7) | 295 949 (36.8) | |
| Year of diagnosis | |||
| 2007–2008 | – | 120 304 (15.0) | NA |
| 2009–2010 | – | 127 051 (15.8) | |
| 2011–2012 | – | 132 911 (16.5) | |
| 2013–2014 | – | 132 133 (16.4) | |
| 2015–2016 | – | 136 091 (16.9) | |
| 2017–2018 | – | 139 179 (17.3) | |
| 2019 | – | 16 071 (2.0) | |
| Cancer site | |||
| Bone sarcoma and PNS | – | 1647 (0.2) | NA |
| Breast | – | 112 300 (14.0) | |
| Bronchopulmonary | – | 103 831 (12.9) | |
| CNS | – | 10 597 (1.3) | |
| Endocrine | – | 32 234 (4.0) | |
| Gastrointestinal | – | 151 560 (18.8) | |
| Genitourinary | – | 169 990 (21.1) | |
| Gynecologic | – | 49 417 (6.1) | |
| Hematopoietic and lymphoma | – | 92 175 (11.5) | |
| Head and neck | – | 19 116 (2.4) | |
| Skin | – | 36 748 (4.6) | |
| Other | – | 24 125 (3.0) | |
| Cancer stage | |||
| 0 | – | 1732 (0.2) | NA |
| I | – | 149 293 (18.6) | |
| II | – | 144 163 (17.9) | |
| III | – | 93 937 (11.7) | |
| IV | – | 107 763 (13.4) | |
| Missing or unknown | – | 306 852 (38.2) | |
Note: CNS = central nervous system, NA = not applicable, PNS = peripheral nervous system.
↵* Imbalance of Elixhauser Comorbidity Index score is indicated by a standardized difference of ≥ 0.10. This covariate was adjusted for in the multivariable model.
↵† The sum of counts does not equal the column total because of individuals with missing information (≤ 1.0%) for this characteristic.