Background
Material and methods
Study design
Study population
Defining outcomes
Use of CPPs
Non-cancer diagnoses
Cancer diagnoses
Total mortality and cancer-specific mortality
Defining covariates
Statistical analysis
Results
Individual baseline characteristics
Characteristics | All CT scans (n=513 162) | CT scans referred by GP (n=228 522) | CT scans referred by the hospital (n=284 640) | Missing values | P-value (χ2 test) |
---|---|---|---|---|---|
Age, n (%) | 0 | <.0001 | |||
18-45 years | 113 376 (22.1) | 48 591 (21.3) | 64 785 (22.8) | ||
46-59 years | 119 654 (23.3) | 52 929 (23.2) | 66 725 (23.4) | ||
60-79 years | 94 850 (40.5) | 94 850 (41.5) | 112 792 (39.6) | ||
≥80 years | 32 152 (14.1) | 32 152 (14.1) | 40 338 (14.2) | ||
Gender, n (%) | 0 | 0.0016 | |||
Female | 262 958 (51.2) | 117 664 (51.5) | 145 294 (51.0) | ||
Male | 250 204 (48.8) | 110 858 (48.5) | 139 346 (49.0) | ||
Country of origin, n (%) | 0 | <.0001 | |||
Danish | 467 068 (91.0) | 209 222 (91.6) | 257 846 (90.6) | ||
Western descent | 15 935 (3.1) | 6 805 (3.0) | 9 130 (3.2) | ||
Non-western descent | 30 159 (5.9) | 12 495 (5.5) | 17 664 (6.2) | ||
Education, n (%) | 15 240 | <.0001 | |||
Low | 183 915 (36.9) | 82 101 (36.9) | 101 814 (36.9) | ||
Medium | 203 898 (41.0) | 91 752 (41.3) | 112 146 (40.7) | ||
High | 110 109 (22.1) | 48 377 (21.8) | 61 732 (22.4) | ||
Affiliation to work market, n (%) | 33 | <.0001 | |||
Employed | 181 309 (35.3) | 83 278 (36.4) | 98 031 (34.4) | ||
Unemployed/social benefits | 90 709 (17.7) | 37 556 (16.4) | 53 153 (18.7) | ||
Under education | 13 536 (2.6) | 5 257 (2.3) | 8 279 (2.9) | ||
Retired/other | 227 575 (44.4) | 102 417 (44.8) | 125 158 (44.0) | ||
Cohabitation status, n (%) | 0 | <.0001 | |||
Married or cohabiting | 305 835 (59.6) | 140 971 (61.7) | 164 864 (57.9) | ||
Single/living alone | 207 327 (40.4) | 87 551 (38.3) | 119 776 (42.1) | ||
Region of residence, n (%) | 0 | <.0001 | |||
Northern DK | 70 310 (13.7) | 36 444 (16.0) | 33 866 (11.9) | ||
Central DK | 106 933 (20.8) | 53 746 (23.5) | 53 187 (18.7) | ||
Southern DK | 131 864 (25.7) | 69 047 (30.2) | 62 817 (22.1) | ||
Capital DK | 142 697 (27.8) | 49 112 (21.5) | 93 585 (32.9) | ||
Zealand DK | 61 358 (12.0) | 20 173 (8.8) | 41 185 (14.5) | ||
Non-cancer morbidity, n (%) | 0 | <.0001 | |||
No morbidities | 360 620 (70.3) | 175 955 (77.0) | 184 665 (64.9) | ||
One morbidity | 102 549 (20.0) | 37 186 (16.3) | 65 363 (23.0) | ||
Two morbidities | 33 517 (6.5) | 10 624 (4.7) | 22 893 (8.0) | ||
Three or more morbidities | 16 476 (3.2) | 4 757 (2.1) | 11 719 (4.1) |
Type and number of CPPs
All CT scans (n=513 162) | CT scans referred by GP (n=228 522) | CT scans referred by the hospital (n=284 640) | Crude OR (95%CI) | P-value | aAdjusted OR (95% CI) | P-value |
---|---|---|---|---|---|---|
Type of first CPP 6 months after index CT | ||||||
None | 166 941 (73.1) | 247 197 (86.9) | (ref) | - | (ref) | - |
NSSC-CPP | 9 899 (4.3) | 3 866 (1.36) | 3.79 (3.65 3.93) | <.0001 | 4.06 (3.90 4.22) | <.0001 |
OS-CPP | 51 682 (22.6) | 33 577 (11.8) | 2.28 (2.25 2.31) | <.0001 | 2.27 (2.23 2.30) | <.0001 |
Total number of CPPs 6 months after index CT | ||||||
0 CPP | 166 941 (73.1) | 247 197 (86.9) | 0.41 (0.41 0.42) | 0.006 | 0.41 (0.40 0.42) | <.0001 |
1 CPP | 50 261 (22.0) | 30 658 (10.8) | (ref) | - | (ref) | - |
2 CPP | 9 387 (4.1) | 5 580 (2.0) | 1.03 (0.99 1.06) | 0.161 | 1.00 (0.96 1.04) | 0.970 |
3 CPP | 1 595 (0.7) | 1 038 (0.4) | 0.94 (0.87 1.02) | 0.110 | 0.90 (0.83 0.98) | 0.015 |
4+CPP | 338 (0.2) | 167 (0.1) | 0.67 (0.04 10.79) | 0.778 | 1.16 (0.95 1.40) | 0.141 |
Cancers and non-cancers
Diagnoses | CT scans referred by GP (n=228 522) | CT scans referred by hospital (n=284 640) | Crude OR (95%CI) | P-value crude | aAdjusted OR (95% CI) | P-value adjusted |
---|---|---|---|---|---|---|
All cancer and selected non-cancer diagnoses | 80 525 (35.2) | 100 637 (35.4) | 1.00 (0.98 1.01) | 0.377 | 1.01 (1.00 1.03) | 0.046 |
All Cancers diagnoses | 20 926 (9.2) | 22 567 (7.9) | 1.17 (1.15 1.19) | <.0001 | 1.12 (1.09 1.14) | <.0001 |
Lung | 5 031 (2.2) | 3 831 (1.3) | 1.65 (1.58 1.72) | <.0001 | 1.62 (1.55 1.69) | <.0001 |
Breast | 2 846 (1.3) | 4 301 (1.5) | 0.82 (0.78 0.86) | <.0001 | 0.77 (0.73 0.81) | <.0001 |
Prostate | 2 541 (1.1) | 3 582 (1.3) | 0.88 (0.84 0.93) | <.0001 | 0.85 (0.81 0.90) | <.0001 |
Colon | 3 203 (1.4) | 3 364 (1.2) | 1.19 (1.13 1.25) | <.0001 | 1.11 (1.05 1.16) | 0.0001 |
Melanoma of skin | 778 (0.3) | 943 (0.3) | 1.03 (0.94 1.13) | 0.573 | 1.02 (0.92 1.13) | 0.7106 |
Bladder | 1 445 (0.6) | 977 (0.3) | 1.85 (1.71 2.01) | <.0001 | 1.80 (1.65 1.96) | <.0001 |
Brain, central nervous system | 477 (0.2) | 421 (0.2) | 1.42 (1.24 1.62) | <.0001 | 1.40 (1.22 1.60) | <.0001 |
Rectum and anus | 1 189 (0.5) | 1 691 (0.6) | 0.88 (0.81 0.94) | 0.0005 | 0.80 (0.74 0.86) | <.0001 |
Non-Hodgkin lymphoma | 905 (0.4) | 1 135 (0.4) | 0.99 (0.91 1.08) | 0.878 | 0.97 (0.88 1.06) | 0.4406 |
Pancreas | 1 006 (0.4) | 792 (0.3) | 1.59 (1.44 1.74) | <.0001 | 1.50 (1.36 1.65) | <.0001 |
Endometrium | 492 (0.2) | 567 (0.2) | 1.08 (0.96 1.22) | 0.2050 | 1.04 (0.92 1.18) | 0.5476 |
Kidney | 1 192 (0.5) | 1 072 (0.4) | 1.39 (1.28 1.51) | <.0001 | 1.37 (1.26 1.49) | <.0001 |
Ovary | 498 (0.2) | 508 (0.2) | 1.22 (1.08 1.39) | 0.0014 | 1.08 (0.95 1.23) | 0.2154 |
Stomach | 392 (0.2) | 441 (0.2) | 1.11 (0.97 1.27) | 0.1403 | 1.03 (0.90 1.19) | 0.6748 |
Selected non-cancer diagnoses | 66 463 (29.1) | 85 865 (30.2) | 0.95 (0.94 0.96) | <.0001 | 0.97 (0.96 0.99) | <.0001 |
Coronary heart disease | 7 519 (3.3) | 15 978 (5.6) | 0.572 (0.560.59) | <.0001 | 0.55 (0.54 0.57) | <.0001 |
Heart failure | 3 309 (1.5) | 6 762 (2.4) | 0.60 (0.58 0.63) | <.0001 | 0.64 (0.61 0.67) | <.0001 |
Peripheral vascular disease | 4 690 (2.1) | 6 890 (2.4) | 0.85 (0.81 0.88) | <.0001 | 0.84 (0.81 0.87) | <.0001 |
Chronic obstructive pulmonary disease | 8 666 (3.8) | 14 515 (5.1) | 0.73 (0.71 0.75) | <.0001 | 0.79 (0.77 0.81) | <.0001 |
Diabetes | 6 078 (2.7) | 8 134 (2.9) | 0.93 (0.90 0.96) | <.0001 | 0.96 (0.93 0.99) | 0.022 |
Liver disease | 2 353 (1.0) | 3 181 (1.1) | 0.92 (0.87 0.97) | 0.0026 | 1.00 (0.94 1.05) | 0.872 |
Thyroid disorders | 3 317 (1.5) | 4 073 (1.4) | 1.02 (0.97 1.06) | 0.539 | 1.03 (0.99 1.09) | 0.1701 |
Kidney disease | 3 618 (1.6) | 4 643 (1.6) | 0.97 (0.93 1.01) | 0.176 | 0.96 (0.92 1.01) | 0.096 |
Inflammatory bowel disease | 2 325 (1.0) | 2 817 (1.0) | 1.03 (0.97 1.09) | 0.321 | 1.06 (1.00 1.12) | 0.042 |
Ulcer | 1 939 (0.9) | 2 930 (1.0) | 0.82 (0.78 0.87) | <.0001 | 0.86 (0.81 0.92) | <.0001 |
Hemiplegia/stroke | 19 427(8.5) | 20 074 (7.1) | 1.23 (1.20 1.25) | <.0001 | 1.30 (1.27 1.33) | <.0001 |
Parkinson disease | 584 (0.3) | 726 (0.3) | 1.00 (0.90 1.12) | 0.9999 | 1.02 (0.91 1.14) | 0.791 |
Multiple sclerosis | 236 (0.1) | 233 (0.1) | 1.26 (1.06 1.52) | 0.011 | 1.43 (1.19 1.72) | 0.0002 |
Epilepsy | 2 063 (0.9) | 3 182 (1.1) | 0.81 (0.76 0.85) | <.0001 | 0.86 (0.81 0.91) | <.0001 |
Dementia | 7 894 (3.5) | 4 730 (1.7) | 2.12 (2.04 2.20) | <.0001 | 2.23 (2.15 2.32) | <.0001 |
Osteoporosis | 4 568 (2.0) | 7 332 (2.6) | 0.77 (0.74 0.80) | <.0001 | 0.70 (0.68 0.73) | <.0001 |
Rheumatoid and connective tissue disease | 3 020 (1.3) | 3 616 (1.3) | 1.04 (0.99 1.09) | 0.106 | 1.04 (0.99 1.09) | 0.145 |
HIV/AIDS | 50 (0.02) | 66 (0.02) | 0.94 (0.65 1.36) | 0.758 | 1.05 (0.72 1.54) | 0.786 |
Depression/ anxiety | 4 940 (2.1) | 6 381 (2.2) | 0.96 (0.93 1.00) | 0.053 | 1.06 (1.02 1.10) | 0.0042 |
Psychotic diseases | 679 (0.3) | 1 427 (0.5) | 0.59 (0.54 0.65) | <.0001 | 0.70 (0.63 0.77) | <.0001 |
Cancers and non-cancers by Region
Diagnoses 6 months after index CT scan by CT scans referred by GP and hospital in each Region Total=513 162, n(%) | Diagnoses 6 months after index CT scan by Region Total= 513 162, n(%) | ||||||
---|---|---|---|---|---|---|---|
Regions and CT-groups | Non-cancer | Cancer | Non-cancer or cancer | Non-cancer | Cancer | Non-cancer or cancer | |
All Regions | CT-GP n=228 522 | 66 463 (29.1) | 20 926 (9.2) | 80 525 (35.2) | 152 328 (29.7) | 43 493 (8.5) | 181 162 (35.3) |
CT-HO n=284 640 | 85 865 (30.2) | 22 567 (7.9) | 100 637 (35.4) | ||||
Adjusted OR (95%CI) | a0.97 (0.96 0.99) | b1.12 (1.09 1.14) | a1.01 (1.00 1.03) | ||||
P -value | <.0001 | <.0001 | 0.046 | ||||
Zealanda | CT-GP n=20 173 | 6 803 (33.7) | 2 178 (10.8) | 8 183 (40.6) | 21 361 (34.3) | 6 088 (9.8) | 25 114 (40.4) |
CT-HO n=41 185 | 14 559 (35.4) | 3 910 (9.5) | 16 931 (41.1) | ||||
Adjusted OR (95%CI) | a1.00 (0.96 1.04) | b1.15 (1.09 1.22) | a1.06 (1.02 1.10) | ||||
P -value | 0.979 | <.0001 | 0.0015 | ||||
Northb | CT-GP n=36 444 | 9 439 (25.9) | 2 868 (7.9) | 11 362 (31.2) | 18 661 (26.5) | 5 496 (7.8) | 22 313 (31.7) |
CT-HO n=33 866 | 9 222 (27.2) | 2628 (7.8) | 10 951 (32.3) | ||||
Adjusted OR (95%CI) | a0.94 (0.90 0.97) | b0.97 (0.92 1.03) | a0.95 (0.91 0.98) | ||||
P -value | 0.0003 | 0.332 | 0.0013 | ||||
Centralb | CT-GP n=53 746 | 16 957 (31.6) | 4 519 (8.4) | 19 981 (37.2) | 33 553 (31.2) | 8 538 (8.0) | 39 277 (36.7) |
CT-HO n=53 187 | 16 596 (31.2) | 4 019 (7.6) | 19 296 (36.3) | ||||
Adjusted OR (95%CI) | a0.99 (0.96 1.01) | b1.05 (1.00 1.10) | a1.01 (0.98 1.03) | ||||
P -value | 0.348 | 0.049 | 0.686 | ||||
Southb | CT-GP n=69 047 | 18 091 (26.2) | 6 503 (9.4) | 22 660 (32.8) | 34 725 (26.3) | 11 508 (8.7) | 42 728 (32.4) |
CT-HO n =62 817 | 16 634 (26.5) | 5 005 (8.0) | 20 068 (32.0) | ||||
Adjusted OR (95%CI) | a0.95 (0.93 0.98) | b1.10 (1.06 1.15) | a1.00 (0.97 1.02) | ||||
P -value | 0.0004 | <.0001 | 0.916 | ||||
Capitalc | CT-GP n =49 112 | 15 173 (30.9) | 4 858 (9.9) | 18 339 (37.3) | 44 027 (30.9) | 11 863 (8.3) | 51 730 (36.3) |
CT-HO n =93 585 | 28 854 (30.8) | 7 005 (7.5) | 33 391 (36.0) | ||||
Adjusted OR (95%) | a0.99 (0.97 1.02) | b1.26 (1.21 1.31) | a1.06 (1.03 1.08) | ||||
P-value | 0.474 | <.0001 | <.0001 |
Total and cancer-specific mortality
Mortality 1 year after index CT scan by CT scans referred by GP and hospital in each Region Total=513 162 | Total mortality one year after index CT scan by Region Total= 513 162 | ||||
---|---|---|---|---|---|
Regions and CT-groups | Total mortality n(%) | Cancer-specific mortality n(%) | Total mortality n(%) | Cancer specific mortality n(%) | |
All Regions | CT-GP n =228 522 | 16 297 (7.13) | 6 804 (3.0) | 41 077 (8.0) | 13 478 (2.6) |
CT-HO n =284 640 | 24 780 (8.7) | 6 674 (2.3) | |||
aAdjusted OR (95 %) | 0.88 (0.86 0.90) | 1.26 (1.21 1.30) | |||
P-value | <.0001 | <.0001 | |||
Zealanda | CT-GP n =20 173 | 1 660 (8.2) | 754 (3.7) | 6 261 (10.2) | 2 021 (3.3) |
CT-HO n =41 185 | 4 601 (11.2) | 1 267 (3.1) | |||
aAdjusted OR (95 %) | 0.85 (0.79 0.90) | 1.28 (1.16 1.41) | |||
P -value | <.0001 | <.0001 | |||
Northb | CT-GP n =36 444 | 2 602 (7.1) | 954 (2.6) | 11 507 (8.1) | 1 823 (2.6) |
CT-HO n =33 866 | 3 147 (9.3) | 869 (2.6) | |||
aAdjusted OR (95%) | 0.78 (0.73 0.83) | 1.00 (0.91 1.10) | |||
P -value | <.0001 | 0.992 | |||
Centralb | CT-GP n =53 746 | 4 025 (7.5) | 1 409 (2.6) | 8 411 (7.9) | 2 569 (2.4) |
CT-HO n =53 187 | 4 386 (8.3) | 1 160 (2.2) | |||
aAdjusted OR (95 %) | 0.92 (0.87 0.96) | 1.15 (1.06 1.25) | |||
P -value | 0.0006 | 0.0006 | |||
Southb | CT-GP n =69 047 | 4 348 (6.3) | 2 080 (3.0) | 9 149 (6.9) | 3 496 (2.7) |
CT-HO n =62 817 | 4 801 (7.6) | 1 416 (2.3) | |||
aAdjusted OR (95 %) | 0.85 (0.81 0.89) | 1.27 (1.18 1.36) | |||
P -value | <.0001 | <.0001 | |||
Capitalc | CT-GP n =49 112 | 3 662 (7.5) | 1 607 (3.3) | 5 749 (8.2) | 3 569 (2.5) |
CT-HO n =93 585 | 7 845 (8.4) | 1 962 (2.1) | |||
aAdjusted OR (95 %) | 0.96 (0.91 1.00) | 1.51 (1.40 1.62) | |||
P -value | 0.048 | <.0001 |