Dietary inflammatory index and its impact on severity and recurrence of Tourette syndrome in children

Table 1 Univariate analysis of tic disorder instability

Item	Stable group (117 cases)	Unstable group (90 cases)	Statistical value	P value
Age (year, mean ± SD)	7.3 ± 2.22	8.0 ± 2.4	0.585	0.561
Gender, n (%)			χ2 = 0.03	0.863
Male	69 (58.97)	52 (57.78)
Female	48 941.02)	38 (42.23)
Guardian’s educational level			Fisher accurate probability test	0.037
Associate degree and below	10	36
Bachelor’s degree	98	23
Bachelor’s degree and above	2	1
Family history			χ2 = 4.276	0.039
Yes	74 (63.24)	44 (44.44)
No	43 (36.75)	46 (51.11)
Coexisting chronic diseases			Fisher accurate probability test	0.064
Recurrent respiratory inflammation	67 (57.26)	75 (83.33)
Digestive dysfunction	23 (19.65)	15 (16.66)
Other chronic diseases	12 (10.25)	0
None	15 (12.82)	10 (11.11)
BMI (kg/m², mean ± SD)	24.23 ± 9.29	23.91 ± 10.22	t = 0.868	0.386
Medication adherence			χ2 = 5.227	< 0.001
Regular	33 (35.76)	7 (7.00)
Irregular	62 (65.26)	83 (93.00)
Electronic device usage (h/day)	3.45 ± 1.24	4.34 ± 1.12	t = 1.025	0.028
Academic pressure
Yes	66 (56.41)	62(68.88)	χ2 = 6.305	0.012
No	51 (43.58)	28 (31.11)
DII score [points, M (P25-P75)]	0.56 (-0.9-1.59)	0.17 (-1.34 to 1.42)	6.723	0.000
Duration of disease			χ2 = 1.372	0.561
Within 6 months	69 (58.97)	50 (55.55)
Over 6 months	48 (41.02)	40 (44.44)

BMI: Body mass index; DII: Dietary inflammatory index.

Table 2 Multivariate analysis of changes in tic disorder condition and assignment of categorical variables

Variable	Assignment explanation
Guardian’s education level	Associate degree and below = 1, bachelor’s = 2, above bachelor’s = 3
DII index	Original value entered
Academic pressure	None = 0; Yes = 1
Electronic device usage	< 4 hours = 1, ≥ 4 hours = 0
Medication adherence	Irregular = 0, Regular = 1
Family history	No = 0, Yes = 1

Table 3 Multifactorial regression analysis results of tic disorder recurrence

Variable	β	SE	Wald χ2	P value	OR (95%CI)
Guardian’s education level	-0.416	0.163	6.281	0.0122	0.666 (0.485-0.915)
DII index	1.033	0.334	9.566	0.0021	2.809 (1.459-5.407)
Academic pressure	0.830	0.287	7.827	0.0062	2.125 (1.242-3.673)
Electronic device usage	0.754	0.274	7.573	0.0052	1.351 (0.499-3.657)
Family history	0.383	0.1566	6.027	0.0142	1.467 (1.080-1.991)
Medication adherence	-0.372	0.138	7.267	0.0071	0.689 (0.526-0.903)

Table 4 Comparison of dietary inflammatory index and inflammatory levels in patients with stable tic disorder severity, mean ± SD

Group	Number of cases	DII	IL-6 (pg/mL)	CRP (mg/L)	TNF-α (pg/mL)
Mild	75	0.45 ± 0.17	40.09 ± 7.01	6.18 ± 1.92	6.03 ± 1.52
Moderate	36	0.61 ± 0.07	52.11 ± 6.72	8.15 ± 3.23	8.42 ± 2.08
Severe	6	0.58 ± 0.12	68.47 ± 8.27	9.23 ± 2.74	12.35 ± 3.17
F value		66.632	60.455	4.785	32.863
P value		< 0.001	< 0.001	0.008	< 0.001

CRP: C-reactive protein; IL-6: Interleukin-6; TNF-α: Tumor necrosis factor-alpha.

Table 5 Comparison of dietary inflammatory index and inflammatory levels in patients with unstable tic disorder severity, mean ± SD

Group	Number of cases	DII	IL-6 (pg/mL)	CRP (mg/L)	TNF-α (pg/mL)
Mild	32	0.35 ± 0.02	42.51 ± 7.14	6.57 ± 1.61	6.24 ± 1.22
Moderate	22	0.67 ± 0.05	51.01 ± 7.09	8.43 ± 2.48	8.27 ± 2.14
Severe	36	1.52 ± 0.21	68.81 ± 8.18	10.97 ± 2.51	12.91 ± 3.08
F value		389.120	89.433	123.715	92.813
P value		< 0.001	< 0.001	< 0.001	< 0.001

CRP: C-reactive protein; IL-6: Interleukin-6; TNF-α: Tumor necrosis factor-alpha.