Risk factors associated with anxiety and depression in patients with inflammatory bowel disease identified using structural equation modeling

Table 1 Clinical characteristics

Variable	Classification	n	%
Age	≥ 18 years	77	31.2
	≥ 40 years	82	33.2
	≥ 60 years	88	35.6
Sex	Male	122	49.4
	Female	125	50.6
BMI (kg/m2)	< 18.5	12	83.4
	18.5-23.9	206	11.7
	≥ 24.0	29	4.9
Course	< 1 year	109	44.1
	≥ 1 year	138	55.9
Disease classification	Crohn’s disease	163	66.0
	Ulcerative colitis	84	34.0
Working condition	Employed	114	46.2
	Unemployed	133	53.8
Place of abode	Urban	173	70.0
	Rural	74	30.0
Standard of culture	≤ Junior high	72	29.2
	High school/vocational	85	34.4
	≥ College	90	36.4
Marital status	Unmarried	97	39.3
	Married	89	36.0
	Divorced/widowed	61	24.7
Average monthly household income	< 3000 yuan	119	48.2
	≥ 3000 yuan	128	51.8
Use of biological agents	Yes	185	74.9
	No	62	25.1
Disease stage	Remission	142	57.5
	Active	105	42.5
Medical insurance	Yes	178	72.1
	No	69	27.9

BMI: Body mass index.

Table 2 Univariate analysis of factors influencing anxiety and depression in patients, median (interquartile rage)

Variable	n	HADS score	t/F	P value
Age			40.605	< 0.001
≥ 18 years	77	22.00 (14.00-25.00)
≥ 40 years	82	17.00 (14.00-19.00)
≥ 60 years	88	14.00 (13.00-16.00)
Sex			62.748	< 0.001
Male	122	14.00 (12.75-16.00)
Female	125	19.00 (15.00-23.00)
BMI (kg/m2)			2.184	0.336
< 18.5	12	18.50 (14.00-22.00)
18.5-23.9	206	16.00 (13.00-20.00)
≥ 24.0	29	14.00 (13.00-18.50)
Course			1.066	0.302
< 1 year	109	15.00 (13.00-20.00)
≥ 1 year	138	16.00 (13.00-20.25)
Disease classification			1.345	0.246
Crohn’s disease	163	15.00 (14.00-21.00)
Ulcerative colitis	84	15.00 (13.00-19.75)
Working condition			183.325	< 0.001
Employed	114	13.00 (12.00-14.00)
Unemployed	133	20.00 (17.00-24.00)
Place of abode			0.089	0.766
Urban	173	16.00 (13.00-20.00)
Rural	74	15.00 (14.00-20.00)
Standard of culture			3.431	0.180
≤ Junior high	72	15.00 (13.00-21.00)
High school/vocational	85	16.00 (14.00-21.00)
≥ College	90	14.00 (13.00-18.00)
Marital status			93.130	< 0.001
Married	89	13.00 (12.00-14.00)
Unmarried	97	18.00 (15.00-20.00)
Divorced/widowed	61	23.00 (15.00-25.00)
Average monthly household income			138.564	< 0.001
< 3000 yuan	119	13.00 (12.00-18.00)
≥ 3000 yuan	128	19.00 (16.25-23.75)
Use of biological agents			0.245	0.620
Yes	185	15.00 (13.00-20.00)
No	62	16.00 (13.00-22.00)
Disease stage			144.762	< 0.001
Remission	142	14.00 (12.75-14.00)
Active	105	21.00 (18.00-24.50)
Medical insurance			0.000	0.990
Yes	178	15.00 (13.00-20.00)
No	69	15.00 (13.00-21.00)

BMI: Body mass index; HADS: Hospital Anxiety and Depression Scale.

Table 3 Coding of variables

Variable	Coding
HADS score	Original value input
Age	≥ 18 years = 2; ≥ 40 years = 1; ≥ 60 years = 0
Sex	Male = 0; female = 1
Working condition	Employed = 0; unemployed = 1
Average monthly household income	< 3000 yuan = 1; ≥ 3000 yuan = 0
Disease stage	Active = 1; remission = 0
Marital status	Married = 0; unmarried = 1; divorced/widowed = 2
PSQI score	Original value input
MCMQ score	Original value input

HADS: Hospital Anxiety and Depression Scale; PSQI: Pittsburgh Sleep Quality Index; MCMQ: Medical Coping Modes Questionnaire.

Table 4 Hierarchical regression analysis of influencing factors

Variable	B	SE	β	t	P value	95%CI
Constant	-17.281	4.695		-3.68	< 0.001	-26.531 to -8.031
Age	1.072	0.155	0.183	6.908	< 0.001	0.766-1.378
Sex	0.750	0.261	0.079	2.877	0.004	0.237-1.264
Working condition	1.118	0.556	0.117	2.009	0.046	0.022-2.213
Marital status	0.715	0.192	0.116	3.718	< 0.001	0.336-1.094
Average monthly household income	0.907	0.446	0.095	2.034	0.043	0.029-1.786
Disease stage	1.147	0.397	0.119	2.887	0.004	0.364-1.929
PSQI score	1.141	0.101	0.537	11.34	< 0.001	0.943-1.339
MCMQ score	0.403	0.112	0.117	3.597	< 0.001	0.182-0.624

F = 191.02, P < 0.01, R² = 0.865, △R² = 0.861. PSQI: Pittsburgh sleep quality index; MCMQ: Medical coping modes questionnaire; CI: Confidence interval.

Table 5 Model fit indices

Index	Reference standard	Observed result	Accept
χ2/df	< 3.00	1.039	Yes
RESEA	< 0.08	0.013	Yes
GFI	> 0.90	0.978	Yes
AGFI	> 0.90	0.949	Yes
NFI	> 0.90	0.976	Yes
IFI	> 0.90	0.999	Yes
CFI	> 0.90	0.999	Yes

RESEA: Root mean square error of approximation; GFI: Goodness of fit index; AGFI: Adjusted goodness of fit index; NFI: Normed fit index; IFI: Incremental fit index; CFI: Comparative fit index.

Table 6 Path analysis results of factors influencing anxiety and depression in patients with inflammatory bowel disease

Influence path	Estimate	SE	t	P value
PSQI to MCMQ	3.223	0.807	3.993	< 0.001
PSQI to HADS	1.859	0.740	2.512	0.012
MCMQ to HADS	0.724	0.121	6.001	< 0.001
Avoidance to MCMQ	1.000
Yield to MCMQ	0.946	0.025	37.275	< 0.001
Confront to MCMQ	-1.563	0.029	-53.412	< 0.001
Anxiety to HADS	1.000
Depression to HADS	0.833	0.085	9.787	< 0.001
Subjective sleep quality to PSQI	0.592	0.115	5.141	< 0.001
Daytime dysfunction to PSQI	0.726	0.158	4.589	< 0.001
Sleep time to PSQI	0.603	0.159	3.797	< 0.001
Time before falling asleep to PSQI	0.294	0.099	2.975	0.003
Sleep efficiency to PSQI	0.472	0.107	4.428	< 0.001
Hypnotic drugs to PSQI	-0.057	0.032	-1.796	0.072
Dyssomnia to PSQI	1.000

PSQI: Pittsburgh Sleep Quality Index; MCMQ: Medical Coping Modes Questionnaire; HADS: Hospital Anxiety and Depression Scale.

Table 7 Path effects of variables on anxiety and depression in patients with inflammatory bowel disease

Path	Direct effect (β)	Indirect effect (β)	Total effect (β)
PSQI to MCMQ	3.223	0.000	3.223
MCMQ to HADS	1.859	2.335	4.194
PSQI to HADS	0.724	0.000	0.724

PSQI: Pittsburgh Sleep Quality Index; MCMQ: Medical Coping Modes Questionnaire; HADS: Hospital Anxiety and Depression Scale.