Intestinal permeability and its association with the patient and disease characteristics in Crohn’s disease

Table 1 Characteristics of the patients with CD (n = 125)

Variables	n (%)
Sex
Males	66 (52.8)
Females	59 (47.2)
Age (yr)
Median (range)	36 (14-66)
Patients with age < 40	76 (60.8)
Patients with age ≥ 40	49 (39.2)
Duration of the disease (mo)
Median (range)	50 (3-432)
Duration < 36 mo	52 (41.6)
Duration ≥ 36 mo	73 (58.4)
Activity of the disease (CDAI)
Median (range)	109 (10-343)
CDAI < 150	80 (64)
CDAI 151-220	29 (23.2)
CDAI 221-400	16 (12.8)
CDAI > 400	0 (0)
Area of involvement of the GI tract
Small intestine only (L1)	16 (12.8)
Large intestine only (L2)	62 (49.6)
Ileo-colonic (L3)	47 (37.6)
UGI involvement (L4)	23 (18.4)
Behaviour of the disease
Non-fistulizing non-stricturing (B1)	74 (59.2)
Stricturing disease (B2)	37 (29.6)
Fistulizing disease (B3)	14 (11.2)
Perianal disease	25 (20)
Extra-intestinal manifestations	49 (39.2)

CD: Crohn’s disease; CDAI: Crohn’s disease activity index.

Table 2 Comparison of intestinal permeability and D-xylose absorption between patients and healthy controls

Parameter	Patients (n = 125)	Controls (n= 22)	P value
Lactulose excretion (%)	0.326 (0.0204-2.76)	0.293 (0.0089-0.665)	0.0391a
Mannitol excretion (%)	12.5 (1.43-43.75)	14.2 (4.95-30.8)	0.4652
Lactulose mannitol ratio (LMR)	0.027 (0.0029-0.278)	0.0164 (0.0018-0.0548)	0.0044a
D-xylose (g/5 g per 5 h)	1.45 (0.32-4.5)	1.89 (0.80-4.73)	0.0277a

All values expressed as median (range);

^aP < 0.05.

Table 3 Relationship between intestinal permeability (log LMR) and characteristics of the patients and disease (n = 125)

Variables	n	Mean LMR (95% CI)	P value
Gender
Males	66	0.036 (0.029, 0.046)	0.0024a
Females	59	0.022 (0.0178, 0.028)
Area of involvement of the GI tractb
Small intestine only (L1)	16	0.028 (0.0175, 0.0447)	0.0001a
Large Intestine only (L2)	62	0.021 (0.0174, 0.0255)
Ileo-colonic (L3)	47	0.0451 (0.0336, 0.0605)
UGI Involvement
Absent	102	0.0268 (0.0224, 0.0321)	0.0406a
Present	23	0.0416 (0.027, 0.062)
Perianal disease
Absent	100	0.028 (0.023, 0.033)	0.3573
Present	25	0.0339 (0.0234, 0.049)
Behavior of the diseased
Non-fistulizing Non-stricturing (B1)	74	0.024 (0.0194, 0.0298)	0.0062a
Stricturing (B2)	37	0.043 (0.032, 0.058)
Fistulizing (B3)	14	0.028 (0.018, 0.042)
Extra intestinal manifestations
Absent	76	0.028 (0.0226, 0.034)	0.5674
Present	49	0.030 (0.0236, 0.040)

Values are expressed as geometric mean (95% CI),

^aP < 0.05; Large intestine only vs ileo-colonic,

^bP = 0.001 < 0.01; Non-fistulizing non-stricturing vs stricturing,

^dP = 0.004 < 0.01.

Table 4 Relationship of LMR with the patient and disease characteristics using Spearman’s correlation coefficient

Variables	r
Age (yr)	-0.1414
Activity of the disease (CDAI)	0.1414
Duration of the disease (mo)	-0.0271
D-xylose (g/5 g per 5 h)	-0.1210

Table 5 Assessment of the effect of disease and patients characteristics on log LMR using multiple regression analysis

Variable	Regression co-efficientβ(95% CI)
	Unadjusted	Adjusted
Sex
Females1
Males	0.39 (0.089, 0.69)	0.429 (0.130, 0.727)a
Area
Small intestine only1
Large intestine only	-0.284 (-0.764, 0.196)	0.002 (-0.539, 0.543)
Ileo-colonic	0.475 (-0.020, 0.971)	0.579 (0.065, 1.09)a
Behaviour
Non-fistulizing non-stricturing1
Stricturing disease	0.587 (0.230, 0.945)	-0.237 (-0.763, 0.288)
Fistulizing disease	0.152 (-0.366, 0.670)	0.085 (-0.457, 0.628)
Upper GI involvement
Absent1
Present	0.437 (0.019, 0.856)	0.233 (-0.163, 0.630)

R² = 23%,

^aP < 0.05, significant sqrt-square-root transformation.

¹Reference category; β: Regression coefficient; CI: Confidence interval.