Frequency and predictors of fructose malabsorption in patients with functional abdominal pain syndrome: A case-control study

Table 1 Baseline characteristics of cases and controls, n (%)/medians (interquartile ranges)

Characteristics	Cases (n = 61)	Controls (n = 31)	P value
Age (years)	30 (15, 58)	30 (18, 48)	0.61
Gender	Males: 29 (47.5)	Males: 16 (51.6)	0.71
Body mass index (kg/m2)	20.83	21.8	0.96
Dietary pattern	Mixed: 17	Mixed: 5	0.21

Table 2 Characteristics of the fructose hydrogen breath testing among cases, medians (interquartile ranges)

Number	Parameters	FHBT positive (n = 16)	FHBT negative (n = 45)	P value
1	FHBT: Baseline H2	4 (1, 13)	5 (1, 10)	0.81
2	FHBT: Peak H2	34.5 (21, 163)	8 (2, 22)	< 0.001
3	Methane: Baseline	2 (0, 8)	2 (0, 11)	0.72
4	Methane: Peak	5.5 (3, 17)	4 (1, 22)	0.27
5	Predominant methane producers (CH4 ≥ 3)	6 (37.5)	17 (37.7)	0.98

FHBT: Fructose hydrogen breath testing.

Table 3 Univariate analysis of conditions and symptoms associated with the detection of fructose malabsorption by a fructose breath test after a 25 g fructose load, n (%)

Characteristics	FHBT positive (n = 16)	FHBT negative (n = 45)	P value
Age (years)	20	31	0.001
Gender	Males: 11 (69)	Males: 18 (40)	0.048
Duration of symptoms (months)	8	8	0.27
Body mass index (kg/m2)	19.7	22.5	0.404
Dietary pattern	Mixed: 8 (50)	Mixed: 9 (20)	0.022
Bristol score (> 4)	3 (19)	3 (7)	0.17
Severity of pain (severe)	3 (19)	15 (33)	0.35
Proton pump inhibitor usage	16 (100)	45 (100)	1.0
Anti-cholinergic usage	5 (31)	13 (29)	1.0
Abdominal distension	0	1	1.0
Belching	2	3	0.60
Flatulence	0	1	1.0
Nausea	2	3	0.62
Incomplete evacuation	2	6	1.0
Mucus in stools	3	2	0.11
Constipation	2	11	0.48
Loose stools	3	3	0.17

FHBT: Fructose hydrogen breath testing.

Table 4 Multivariate analysis for predictors of fructose malabsorption among functional abdominal pain syndrome

Variable	Odds ratio (95%CI)	P value
Age	1.093 (1.010-1.182)	0.027
Gender	0.269 (0.070-1.027)	0.055
Diet	3.140 (0.801-12.307)	0.101