Intestinal complications in patients with Crohn’s disease in the Brazilian public healthcare system between 2011 and 2020

Table 1 Demographic characteristics and follow-up of patients with Crohn’s disease at Sistema Único de Saúde: General, conventional therapy-only, and anti-tumor necrosis factor therapy population, n (%)

	General patients with CD	CVT-only	Anti-TNF therapy
Patients	16809 (100)	12163 (72)	4646 (28)
Age, yr
Mean (SD)	44.09 (15.38)4	46.37 (15.42)	39.98 (13.72)5
Median (IQR)	43.27 (31.31–55.33)4	46.06 (34.10-57.62)	37.53 (28.59-50.47)5
Gender
Male	6804 (40)	4686 (39)	2118 (46)
Female	10005 (60)	7477 (61)	2528 (54)
Ethnicity, n (%)
Caucasian	8877 (53)	6214 (51)	2663 (57)
Mixed	5002 (29)	3108 (26)	1330 (29)
Black	622 (4)	451 (4)	171 (4)
Missing/others	2308 (14)	2390 (19)	482 (10)
Region of residence
Southeast	10241 (61)	7085 (58)	3156 (68)
South	2369 (14)	1765 (15)	604 (13)
Midwest	756 (4)	491 (4)	265 (6)
Northeast	3188 (19)	2668 (22)	520 (11)
North	254 (2)	153 (1.3)	101 (2)
Missing	1 (0)	1 (0.01)	0 (0)
Follow-up time1, yr
Mean (SD)	4.44 (2.37)	4.3 (2.36)	4.86 (2.35)
Median (IQR)	4.34 (2.42–6.34)	4.17 (2.25–6.17)	4.84 (2.92–6.84)
CVT
Mesalazine	12423 (74)	9376 (77)	3145 (68)
Sulfasalazine	2458 (15)	1864 (15)	619 (13)
Azathioprine	7078 (42)	4012 (33)	3126 (67)
Methotrexate	318 (2)	180 (1.5)	140 (3)
Anti-TNF therapy
Infliximab	2737 (16)	-	2737 (59)
Adalimumab	2378 (14)	-	2378 (51)
Certolizumab	145 (0.8)	-	145 (3)
Time using CVT2, years
Mean (SD)	3.22 (2.46)	3.16 (2.46)	1.84 (1.75)
Median (IQR)	2.67 (1.08–5.00)	2.59 (1.00–4.92)	1.25 (0.50–2.61)
Time using anti-TNF therapy3, yr
Mean (SD)	-	-	2.39 (2.06)
Median (IQR)	-	-	1.76 (0.67–3.67)
Time using CVT therapy prior to anti-TNF therapy
Mean (SD)	-	1.84 (1.75)	-
Median (IQR)	-	1.25 (0.50–2.61)	-
Immunosuppressant therapy prior to anti-TNF therapy, n (%)	-	-	2603 (56)

¹Time since index date conventional therapy up to the last date of patient information available in the database.

²Calculated based on the index date and the last claim of conventional therapy.

³Calculated based on the anti-tumor necrosis factor drug initiation date and the last date of patient information available in the database.

⁴Age at the index date (conventional therapy initiation).

⁵Age at the initiation of anti-tumor necrosis factor therapy.

Conventional therapy and/or anti-tumor necrosis factor therapy describes the proportion of patients who have used each drug. Patients could use one or more drugs, alone or in combination. Immunosuppressant therapy: Azathioprine and/or methotrexate. CD: Crohn’s disease; CVT: Conventional therapy; SUS: Sistema Único de Saúde; TNF: Tumor necrosis factor; IQR: Interquartile range.

Table 2 Incidence rate of intestinal complications (combined and segregated by type of intestinal complications) in general population with Crohn’s disease (n = 16809), patients with no evidence of anti-tumor necrosis factor therapy (conventional therapy-only, n = 12163), and patients with evidence of anti-tumor necrosis factor therapy (n = 4646)

	Total number of events	First event1 (n)	PY	IR per 100 PY (95%CI)
General patients with CD (n = 16809)
Overall (combined)	14697	4633	61931.84	7.48 (7.27–7.68)
Associated disease	9429	4162	63123.61	6.59 (6.39–6.78)
Procedure-related	4707	2706	67528.54	4.00 (3.85–4.15)
CD hospitalization-related	561	454	73645.51	0.61 (0.55–0.67)
CVT-only (n = 12163)
Overall	6415	3026	44431.39	6.8105 (6.5763–7.0447)
Associated disease	5890	2739	45060.27	6.0785 (5.8579–6.2991)
Procedure-related	2934	1768	47820.30	3.6972 (3.5281–3.8663)
CD-related hospitalization	286	247	51654.41	0.5782 (0.4187–0.5377)
Evidence of anti-TNF therapy (4646)
Overall	3928	1607	17500.45	9.1826 (8.7548–9.6105)
Associated disease	3539	1423	18063.34	7.8778 (7.485–8.2707)
Procedure-related	1773	938	19708.24	4.7594 (4.4622–5.0567)
CD hospitalization-related	275	207	21991.1	0.9413 (0.8137–1.0689)

¹Counted only the first intestinal complication (number of patients), but patients could present more than one intestinal complication or type of intestinal complications.

PY: Patient year [sum time of all patients under risk – since index date up to date of first intestinal complications (IC, patients with ICs) or date of last available data (patients without ICs)]. Prior to anti-tumor necrosis factor (anti-TNF) therapy: Since index date up to date of first IC or up to date of anti-TNF therapy initiation. After anti-TNF therapy: Since date of anti-TNF therapy initiation up to date of first IC or up to date of last available data (without ICs). Associated disease according to ICD-10 code: International Classification Disease - 10^th edition. CD: Crohn’s disease; CVT: Conventional therapy; ICs: intestinal complications; IR: Incidence rate = n of patients with event/PY × 100; TNF: Tumor necrosis factor.

Table 3 Description of the most common intestinal complications reported as associated disease or procedure predefined in general population with Crohn’s disease (n = 16809)

Associated disease (ICD-10–related complications)	Description	Number of patients with ICs associated diseases (n = 4162)	Percentage (%)
K603	Anal fistula	1270	31
K610	Anal abscess	835	20
R100	Acute abdomen	422	10
K612	Anorectal abscess	406	10
K635	Polyp of colon	401	10
K629	Disease of anus and rectum, unspecified	350	8
K632	Fistula of intestine	267	6
K631	Perforation of intestine (nontraumatic)	251	6
K602	Anal fissure, unspecified	229	6
K601	Chronic anal fissure	174	4
Procedure-related ICs		Number of patients with procedure-related ICs (n = 2706)
407020276	Fistulotomy	1308	48
407020136	Anorectal abscess drainage	785	29
407020217	Internal sphincterotomy	350	13
407020179	Enterectomy	129	5
407020144	Ischiorectal abscess drainage	110	4
407020403	Retossigmoidectomy	105	4
407020209	Enterotomy	92	3
407020101	Colostomy	89	3
407020390	Body removed – rectum or colon polyps	83	3
407020225	Excision of anorectal tumor	78	3

Enterectomy is a surgical procedure (incision) performed to remove a part of the intestine (either small or large). CD: Crohn’s disease; ICs: Intestinal complications; ICD-10: International classification of diseases – 10^th revision.