Table 2.
Crude incidence rates per 100 000 person-years, number of cancer cases and SIRs of non-Hodgkin's lymphoma and Hodgkin’s lymphoma in patients with IBD in Norway and Sweden, 1987–2016*
| Parameters | Non-Hodgkin’s lymphoma | Hodgkin’s lymphoma | ||||
| IR (95% CI) | O/E | SIR (95% CI) | IR (95% CI) | O/E | SIR (95% CI) | |
| Total | 30.8 (27.8 to 34.2) | 369/277.8 | 1.3 (1.2 to 1.5) | 3.7 (2.7 to 4.9) | 44/28.5 | 1.5 (1.1 to 2.1) |
| Sex | ||||||
| Female | 24.8 (20.9 to 29.2) | 145/109.4 | 1.3 (1.1 to 1.6) | 2.7 (1.6 to 4.4) | 16/11.6 | 1.4 (0.8 to 2.2) |
| Male | 36.6 (32.0 to 41.7) | 224/168.4 | 1.3 (1.2 to 1.5) | 4.6 (3.0 to 6.6) | 28/16.8 | 1.7 (1.1 to 2.4) |
| Age (years) at IBD diagnosis | ||||||
| <20 | 5.9 (2.6 to 11.7) | 8/2.1 | 3.9 (1.7 to 7.6) | 3.0 (0.8 to 7.6) | 4/4.3 | 0.9 (0.3 to 2.4) |
| 20–39 | 9.8 (7.2 to 13.0) | 48/28.7 | 1.7 (1.2 to 2.2) | 3.5 (2.0 to 5.6) | 17/11.7 | 1.5 (0.8 to 2.3) |
| 40–59 | 39.5 (33.6 to 46.1) | 161/122.8 | 1.3 (1.1 to 1.5) | 3.2 (1.7 to 5.4) | 13/8 | 1.6 (0.9 to 2.8) |
| 60+ | 92.2 (78.1 to 08.1) | 152/124.2 | 1.2 (1.0 to 1.4) | 6.1 (2.9 to 11.2) | 10/4.4 | 2.3 (1.1 to 4.2) |
| P for trend | 0.119 | 0.330 | ||||
| Calendar year of IBD diagnosis† | ||||||
| 1987/1993–2002 | 32.1 (28.4 to 36.2) | 268/198.4 | 1.4 (1.2 to 1.5) | 3.5 (2.3 to 5.0) | 29/19.1 | 1.5 (1.0 to 2.2) |
| 2003–2015/2016 | 27.9 (22.7 to 33.9) | 101/79.4 | 1.3 (1.0 to 1.5) | 4.1 (2.3 to 6.8) | 15/9.4 | 1.6 (0.9 to 2.6) |
| IBD subtype | ||||||
| Ulcerative colitis | 32.1 (28.1 to 36.5) | 231/178.1 | 1.3 (1.1 to 1.5) | 3.8 (2.5 to 5.5) | 27/17.1 | 1.6 (1.0 to 2.3) |
| Crohn’s disease | 29.4 (24.3 to 35.2) | 117/83 | 1.4 (1.2 to 1.7) | 4.0 (2.3 to 6.5) | 16/9.5 | 1.7 (1.0 to 2.7) |
| IBD unclassified | 26.8 (16.6 to 40.9) | 21/16.7 | 1.3 (0.8 to 1.9) | 1.3 (0.0 to 7.1) | 1/1.9 | 0.5 (0.0 to 2.9) |
| Extent of ulcerative colitis | ||||||
| E1 (proctitis) | 30.7 (19.5 to 46.1) | 23/17.9 | 1.3 (0.8 to 1.9) | 2.7 (0.3 to 9.7) | 2/1.7 | 1.2 (0.1 to 4.2) |
| E2 (left-sided) | 31.2 (23.0 to 41.4) | 48/39.5 | 1.2 (0.9 to 1.6) | 5.9 (2.7 to 11.1) | 9/3.5 | 2.5 (1.2 to 4.8) |
| E3 (extensive) | 34.3 (27.6 to 42.1) | 91/69.2 | 1.3 (1.1 to 1.6) | 3.0 (1.3 to 5.9) | 8/6.4 | 1.3 (0.5 to 2.5) |
| Ex (not defined) | 30.6 (23.8 to 38.7) | 69/51.5 | 1.3 (1.0 to 1.7) | 3.5 (1.5 to 7.0) | 8/5.4 | 1.5 (0.6 to 2.9) |
| Location of Crohn’s disease‡ | ||||||
| L1 (terminal ileitis) | 34.4 (21.0 to 53.1) | 20/15.5 | 1.3 (0.8 to 2.0) | 1.7 (0.0 to 9.6) | 1/1.4 | 0.7 (0.0 to 4.0) |
| L2 (colonic) | 37.3 (24.6 to 54.2) | 27/16.2 | 1.7 (1.1 to 2.4) | 6.9 (2.2 to 16.1) | 5/1.7 | 2.9 (0.9 to 6.8) |
| L3 (ileocecal) | 27.5 (20.2 to 36.5) | 47/35.9 | 1.3 (1.0 to 1.7) | 3.5 (1.3 to 7.6) | 6/4.0 | 1.5 (0.6 to 3.3) |
| Lx (not defined) | 23.8 (15.1 to 35.8) | 23/15.4 | 1.5 (0.9 to 2.2) | 4.1 (1.1 to 10.6) | 4/2.4 | 1.7 (0.5 to 4.3) |
| Behaviour of Crohn’s disease‡ | ||||||
| B1 (non-structuring/non-penetrating) | 25.9 (20.2 to 32.6) | 72/55.8 | 1.3 (1.0 to 1.6) | 4.3 (2.2 to 7.5) | 12/6.7 | 1.8 (0.9 to 3.1) |
| B2 (stricturing) | 46.4 (32.7 to 63.9) | 37/21.2 | 1.7 (1.2 to 2.4) | - | 0/1.8 | - |
| B3 (penetrating) | 23.0 (7.5 to 53.7) | 5/2.8 | 1.8 (0.6 to 4.1) | 9.2 (1.1 to 33.3) | 2/0.6 | 3.6 (0.4 to 13.0) |
| B2B3 (stricturing and penetrating) | 16.5 (3.4 to 48.1) | 3/3.2 | 0.9 (0.2 to 2.7) | 11.0 (1.3 to 9.7) | 2/0.4 | 4.7 (0.6 to 17.1) |
| Perianal disease of Crohn’s disease‡ | ||||||
| No | 25.0 (19.7 to 31.2) | 77/66.4 | 1.2 (0.9 to 1.4) | 3.2 (1.6 to 6.0) | 10/7.3 | 1.4 (0.7 to 2.5) |
| Yes | 44.5 (31.8 to 60.5) | 40/16.6 | 2.4 (1.7 to 3.3) | 6.7 (2.4 to 14.5) | 6/2.2 | 2.8 (1.0 to 6.1) |
| Years since IBD diagnosis | ||||||
| >1–2 | 31.2 (21.9 to 43.0) | 37/22.4 | 1.7 (1.2 to 2.3) | 3.4 (0.9 to 8.6) | 4/2.9 | 1.4 (0.4 to 3.6) |
| >2–5 | 28.1 (22.5 to 34.6) | 88/63.3 | 1.4 (1.1 to 1.7) | 1.6 (0.5 to 3.7) | 5/7.5 | 0.7 (0.2 to 1.5) |
| >5–10 | 29.5 (24.3 to 35.4) | 115/89.9 | 1.3 (1.1 to 1.5) | 4.9 (2.9 to 7.6) | 19/9.4 | 2.0 (1.2 to 3.2) |
| 10+ | 34.5 (28.8 to 41.0) | 129/102.3 | 1.3 (1.1 to 1.5) | 4.3 (2.4 to 6.9) | 16/8.7 | 1.8 (1.1 to 3.0) |
| P for trend | 0.377 | 0.312 | ||||
| PSC§ | ||||||
| No | 30.0 (26.9 to 33.3) | 349/271.9 | 1.3 (1.2 to 1.4) | 3.5 (2.5 to 4.8) | 41/27.7 | 1.5 (1.1 to 2.0) |
| Yes | 63.8 (39.0 to 98.6) | 20/5.9 | 3.4 (2.1 to 5.2) | 10.0 (2.1 to 9.3) | 3/0.8 | 3.9 (0.8 to 11.4) |
| Bowel surgery during follow-up¶ | ||||||
| No | 29.9 (26.6 to 33.5) | 303/240.9 | 1.3 (1.1 to 1.4) | 3.5 (2.4 to 4.8) | 34/23.3 | 1.5 (1.0 to 2.0) |
| Yes | 36.0 (27.8 to 45.8) | 66/36.9 | 1.8 (1.4 to 2.3) | 5.5 (2.6 to 10.0) | 10/4.4 | 2.3 (1.1 to 4.1) |
*All patients were at risk from 1 year after IBD diagnosis.
†Patients diagnosed before 2002 could represent a mix of prevalent and incident patients with IBD as outpatient data were gradually included in hospital databases and the Swedish national patient register.
‡Definitions and diagnostic codes were used according to the Montreal classifications using ICD-9 and ICD-10 in Norwegian data and using ICD-10 in Swedish data, representing maximum disease involvement during follow-up. See online supplemental table 2 for definitions.
§Patients with PSC contributed person-time to the non-PSC group until the date of PSC diagnosis.
¶Bowel surgeries included colectomy, small bowel resection, rectal resection and colon resection during follow-up. See online supplemental table 3 for definitions.
E, expected number of cases; IBD, inflammatory bowel disease; ICD, International Classification of Disease; IR, incidence ratio, per 100 000 person-years; O, observed number of cases; PSC, primary sclerosing cholangitis; SIR, standardised incidence ratio.