Predictive effect of lipopolysaccharide-stimulated inflammatory cytokines on symptoms of generalized anxiety disorder

Table 1 Demographic and clinical characteristics, n (%)

Index	Control group	Generalized anxiety disorder group	t/χ2	P value
Age (yr)	53.79 ± 16.23	58.30 ± 13.70	1.863	0.065
Sex (male/female)	25/45	39/50	1.812	0.178
Body mass index (kg/m2)	24.55 ± 2.06	24.46 ± 3.24	0.291	0.760
Smoking history	19 (27.14)	18 (20.22)	1.050	0.305
Drinking history	9 (12.85)	8 (8.99)	0.001	0.529
Diabetes	10 (14.29)	13 (14.60)	0.030	0.954
Hypertension	33 (47.14)	46 (51.69)	0.323	0.570
Coronary heart disease	8 (11.42)	18 (20.22)	2.216	0.137
Hyperlipidemia	7 (10.00)	10 (11.23)	0.063	0.802
Cerebral infarction	10 (14.28)	15 (16.85)	0.195	0.659

Table 2 Comparison of levels of inflammation-related cytokines between the two groups

Inflammatory factor (normal range)	Control group (mean ± SD)	Generalized anxiety disorder group (mean ± SD)	t value	P value
IL-1β (0-12.4 pg/mL)	1.69 ± 1.04	1.96 ± 2.21	1.024	0.308
IL-2 (0-5.71 pg/mL)	1.45 ± 0.98	1.78 ± 1.40	1.684	0.094
IL-4 (0-3 pg/mL)	1.68 ± 1.14	2.19 ± 1.82	2.040	0.043
IL-5 (0-3.10 pg/mL)	1.27 ± 0.58	2.18 ± 1.80	4.044	0.001
IL-6 (0-7 pg/mL)	5.03 ± 3.11	5.06 ± 3.98	-0.40	0.968
IL-8 (0-20.60 pg/mL)	30.59 ± 41.33	57.53 ± 230.29	1.081	0.336
IL-10 (0-4.91 pg/mL)	2.30 ± 0.82	3.66 ± 5.86	2.163	0.056
TNF-α (0-4.60 pg/mL)	2.05 ± 1.25	2.42 ± 2.67	1.069	0.287
IFN-γ (0-7.42 pg/mL)	1.77 ± 1.29	2.02 ± 1.59	1.056	0.292
IL-17A (0-20.6 pg/mL)	7.23 ± 4.84	4.27 ± 4.42	-3.749	0.001
IL-12p70 (0-3.4 pg/mL)	2.07 ± 1.40	2.55 ± 2.54	1.443	0.151
IFN-α (0-8.5 pg/mL)	1.80 ± 1.20	3.42 ± 10.42	1.460	0.148

IFN: Interferon; IL: Interleukin; TNF: Tumor necrosis factor.

Table 3 Inflammation-related cytokine levels after lipopolysaccharide stimulation

Inflammatory factor (normal range)	Control group (mean ± SD)	Generalized anxiety disorder group (mean ± SD)	t value	P value
IL-1β (0-12.4 pg/mL)	1592.06 ± 622.43	1538.99 ± 844.21	-0.440	0.660
IL-2 (0-5.71 pg/mL)	1.12 ± 0.67	1.13 ± 0.85	0.082	0.935
IL-4 (0-3 pg/mL)	1.44 ± 0.75	1.25 ± 0.77	-1.568	0.119
IL-5 (0-3.10 pg/mL)	1.09 ± 0.68	1.04 ± 0.39	-0.625	0.534
IL-6 (0-7 pg/mL)	14354.85 ± 1420.62	14657.66 ± 3347.42	0.173	0.443
IL-8 (0-20.60 pg/mL)	9515.79 ± 3803.61	11351.12 ± 6349.79	2.306	0.025
IL-10 (0-4.91 pg/mL)	1244.80 ± 2727.53	1049.45 ± 2877.97	-0.433	0.665
TNF-α (0-4.60 pg/mL)	2666.29 ± 1272.87	3197.81 ± 1887.78	1.676	0.045
IFN-γ (0-7.42 pg/mL)	34.72 ± 166.81	23.77 ± 74.81	-0.553	0.581
IL-17 (0-20.6 pg/mL)	26.91 ± 22.767	28.78 ± 30.53	0.426	0.671
IL-12p70 (0-3.4 pg/mL)	2.50 ± 2.84	1.94 ± 1.44	-1.633	0.104
IFN-α (0-8.5 pg/mL)	2.42 ± 2.24	2.01 ± 2.21	-1.181	0.240

IFN: Interferon; IL: Interleukin; TNF: Tumor necrosis factor.

Table 4 Correlation between inflammatory factors and Hamilton Anxiety Rating Scale scores

Inflammatory factor	Correlation with HAMA scores before LPS stimulation		Correlation with HAMA scores after LPS- stimulation
	r value	P value	r value	P value
IL-1β	0.118	0.271	0.219	0.039
IL-2	0.131	0.220	-0.20	0.852
IL-4	0.106	0.322	0.663	0.558
IL-5	-0.087	0.420	-0.042	0.698
IL-6	0.058	0.590	0.379	< 0.001
IL-8	0.149	0.164	0.640	< 0.001
IL-10	0.050	0.640	-2.92	0.005
TNF-α	0.108	0.313	0.621	< 0.001
IFN-γ	0.049	0.647	0.153	0.151
IL-17A	0.245	0.021	0.138	0.197
IL-12p70	0.118	0.270	0.091	0.399
IFN-α	0.036	0.737	0.144	0.178

IFN: Interferon; IL: Interleukin; TNF: Tumor necrosis factor; HAMA: Hamilton Anxiety Rating Scale; LPS: Lipopolysaccharide.

Table 5 Correlation between inflammatory factors and mental anxiety and somatic anxiety

Inflammatory factor	Correlation with mental anxiety		Correlation with somatic anxiety
	r value	P value	r value	P value
IL-1β	0.148	0.166	0.236	0.026
IL-6	0.374	< 0.0001	0.304	0.004
IL-8	0.495	< 0.0001	0.587	< 0.0001
IL-10	-0.224	< 0.035	-0.307	0.003
TNF-α	0.644	< 0.0001	0.503	< 0.0001

IL: Interleukin; TNF: Tumor necrosis factor.

Table 6 Correlation between inflammatory factors and factors of somatic anxiety

Somatic anxiety factor (symptoms)	Correlation with inflammatory factors
	IL-1β		IL-8		IL- 10
	r value	P value	r value	P value	r value	P value
Muscular system	0.26	0.808	0.175	0.101	-0.20	0.853
Sensory system	0.143	0.182	0.114	0.288	-1.69	0.114
Cardiovascular system	0.30	0.004	0.119	0.265	0.029	0.788
Respiratory system	0.012	0.908	0.118	0.273	-0.092	0.392
Gastrointestinal system	-0.052	0.630	0.027	0.801	-0.503	< 0.0001
Genitourinary system	0.102	0.341	0.322	0.002	-0.124	0.245
Autonomic nervous system	0.077	0.471	0.517	< 0.0001	-0.040	0.707