Prevention of post-operative recurrence of Crohn’s disease

Table 1 Risk factors for postoperative recurrence

Risk factor	Strength of association (OR)	Grade of evidence1
Active smoking	2 (1.3-3.4)[18]	B
Penetrating disease	1.5 (1.2-1.9)[26]	B
Prior resection	1.8 (1.1-2.9)[22]	B
Myenteric plexitis	1.9 (1.0-3.5)[33]	C

¹Based on American Gastroenterological Association guidelines. A: Multiple, well-designed randomized controlled trials; B: At least one large well-designed clinical trial with or without randomization; C: Based on clinical experience, expert committees or descriptive studies.

Table 2 Recurrence rates with each agent discussed (range) from randomized controlled trials, vs placebo rates

Agent	Endoscopic recurrence		Clinical recurrence
	Drug	Placebo	Drug	Placebo
Mesalamine	5%-51%	50%	11%-16%	19%-23%
Thiopurines	2%-22%	50%	0%-36%	10%-50%
Anti-TNF	0%-21%1	81%-85%1	0%-20%	25%-46%
Antibiotics	13%	43%	7%-24%	25%-38%
Probiotics2	9%-21%	15%-16%	9%-17%	6%-14%
Budesonide	52%	57%	57%3	70%3

Ranges of reported endoscopic and clinical recurrences for various therapies and the range of placebo reports from those trials. Endoscopic recurrence rates are for severe (≥ i2) recurrence unless otherwise stated. Follow-up time is 12 mo unless otherwise stated.

¹Any endoscopic recurrence;

²Three to twelve months follow-up;

³Combined clinical and endoscopic recurrence. TNF: Tumour necrosis factor.