Predictive value of alarm symptoms in Rome IV irritable bowel syndrome: A multicenter cross-sectional study

Table 1 Prevalence of organic disease according to clinical factors and alarm symptoms (n = 730), n (%)

Characteristics	IBS (n = 654)	Organic disease (n = 76)	P value
Female	307 (46.94)	27 (35.53)	0.059
Onset age (yr)1			0.682
> 50	268 (40.98)	33 (43.42)
≤ 50	386 (59.02)	43 (56.58)
BMI (kg/m2)			0.360
< 18.5	37 (5.66)	1 (1.32)
18.5-23.9	357 (54.59)	45 (59.21)
24.0-27.9	212 (32.42)	26 (34.21)
≥ 28	48 (7.34)	4 (5.26)
Marital status			0.014
Married	592 (90.52)	60 (78.95)
Never married	46 (7.03)	11 (14.47)
Divorced	3 (0.46)	1 (1.32)
Widowed	13 (1.99)	4 (5.26)
Educational level			0.446
Elementary	88 (13.46)	13 (17.11)
Junior high school	176 (26.91)	14 (18.42)
High school	153 (23.39)	19 (25.00)
University or technical college	218 (33.33)	29 (30.86)
Postgraduate	19 (2.91)	1 (1.32)
Alcohol use			0.394
Almost not	488 (74.62)	52 (68.42)
Previous	45 (6.88)	5 (6.58)
At present	121 (18.50)	19 (25.00)
Tobacco use			0.102
Almost not	456 (69.72)	44 (57.89)
Previous	49 (7.49)	7 (9.21)
At present	149 (22.78)	25 (32.89)
Exercise time			0.406
< 0.5 h/d	154 (23.55)	24 (31.58)
≥ 0.5 h/d	183 (27.98)	21 (27.63)
≥ 1 h/d	139 (21.25)	12 (17.11)
≥ 2 h/d	178 (27.22)	19 (25.00)
History of GI infection	72 (11.01)	6 (7.89)	0.405
Poor sleep quality	236 (36.09)	26 (34.21)	0.747
Dietary factor			0.900
Raw or cold food	131 (20.03)	17 (22.37)
Spicy food	258 (39.45)	37 (48.68)
Lipid food	119 (18.20)	18 (23.68)
Milk and dairy products	95 (14.53)	9 (11.84)
Animal protein	32 (4.89)	4 (5.26)
FODMAP diet	103 (15.75)	12 (15.79)
Psychological self-rating scale2
Anxiety			0.507
No	207 (71.13)	26 (70.27)
Mild	52 (17.87)	5 (13.51)
Moderate	27 (9.28)	6 (16.22)
Severe	5 (1.72)	0 (0)
Depression			0.672
No	184 (63.23)	26 (70.27)
Mild	53 (18.21)	4 (10.81)
Moderate	43 (14.78)	5 (13.51)
Severe	11 (3.78)	2 (5.41)
Medical expenses (RMB)			0.197
< 500 yuan	120 (18.35)	17 (22.37)
500-1000 yuan	174 (26.61)	13 (17.11)
1000-3000 yuan	138 (21.10)	16 (21.05)
3000-5000 yuan	74 (11.31)	6 (7.89)
≥ 5000 yuan	148 (22.63)	24 (31.58)
Rectal bleeding1	115 (17.58)	20 (26.32)	0.063
Fecal occult blood1	75 (11.47)	18 (23.68)	0.003
Unintended weight loss (kg)1,3			0.003
Without	507 (77.52)	47 (61.84)
< 2.5	68 (10.40)	16 (21.05)
2.5-5.0	40 (6.12)	7 (9.21)
5.0-7.5	35 (5.35)	3 (3.95)
≥ 7.5	4 (0.61)	3 (3.95)
Anemia1	37 (5.66)	11 (14.47)	0.007
Fever1	17 (2.60)	1 (1.32)	0.770
Nocturnal symptoms1	164 (25.08)	17 (22.37)	0.605
Family history of IBD, CRC or celiac disease1	55 (8.41)	5 (6.58)	0.582

¹Referred to alarm symptom.

²Only data of 328 patients were available.

³Referred to weight loss in the last 3 mo. BMI: Body mass index; CRC: Colorectal cancer; FODMAP: Fermentable Oligo-, Di-, Mono-saccharides And Polyols; GI: Gastrointestinal; IBD: Inflammatory bowel disease; IBS: Irritable bowel syndrome.

Table 2 Multivariate analysis for clinical factors and alarm symptoms¹

Characteristics	OR (95%CI)	P value	Partial regression coefficient
Female (ref male)	0.560 (0.330, 0.949)	0.031	-0.580
Marital status		0.030
Married	—	—	—
Never married	2.499 (1.199, 5.209)	0.015	0.916
Divorced	1.184 (0.088,15.956)	0.899	0.169
Widowed	3.260 (0.964,11.029)	0.057	1.182
Anemia (ref absence)	2.825 (1.273, 6.267)	0.011	1.038
Fecal occult blood (ref absence)	1.940 (1.041, 3.613)	0.037	0.663
Unintended weight loss (kg)2		0.009
Without	—	—	—
< 2.5	2.389 (1.255, 4.548)	0.008	0.871
2.5-5.0	1.868 (0.751, 4.642)	0.179	0.625
5.0-7.5	0.904 (0.263, 3.110)	0.872	-0.101
≥ 7.5	8.027 (1.638,39.335)	0.010	2.083

¹All factors in Table 1, except the psychological self-rating scale were included in the logistic regression analysis.

²Referred to weight loss in the last 3 mo. CI: Confidence interval; OR: Odds ratio.

Table 3 Prevalence of organic disease according to number of alarm symptoms

Number of alarm symptoms	Number of patients (n = 730)	Patients with organic disease, n (%)	P value
0	180	15 (8.33)	0.013
1	250	21 (8.40)
2	180	20 (11.11)
3	91	12 (13.19)
4	19	2 (10.53)
5	7	3 (42.86)
6	3	2 (66.67)

Table 4 Utility of alarm symptoms for identifying organic disease

Alarm symptoms	PPV (%)
Onset age > 50 yr	10.96
Rectal bleeding	14.81
Fecal occult blood	19.35
Unintended weight loss1	16.48
Anemia	22.92
Fever	5.56
Nocturnal symptoms	9.39
Family history of IBD, CRC or celiac disease	8.33
Anemia + fecal occult blood	69.23
Anemia + unintended weight loss	38.89
Fecal occult blood + unintended weight loss	30.00
Anemia + fecal occult blood + unintended weight loss	100.00

¹Referred to weight loss in the last 3 mo. CRC: Colorectal cancer; IBD: Inflammatory bowel disease; PPV: Positive predictive value.

Table 5 The accuracy of alarm symptoms in diagnosing irritable bowel syndrome

	Colonoscopy findings		PPV (%)	Missed diagnosis (%)
	IBS	Organic disease
Without considering alarm symptoms	654	76	89.59	—
All alarm symptoms considered
Absence (predicted IBS)	165	15	91.67	74.77
Presence (predicted organic disease)	489	61
Certain alarm symptoms considered1
Absence (predicted IBS)	431	37	92.09	34.10
Presence (predicted organic disease)	223	39

¹Referred to anemia, fecal occult blood and unintended weight loss. IBS: Irritable bowel syndrome; PPV: Positive predictive value.

Table 6 Colonoscopy findings in suspected irritable bowel syndrome patients

Colonoscopy findings	Number	Percentage (%)
Ulcerative colitis	8	1.10
Non-IBD and noninfectious colitis	42	5.75
CRC	11	1.51
Terminal ileitis	18	2.47
Total organic diseases	76	10.41

CRC: Colorectal cancer; IBD: Inflammatory bowel disease.