Table 2.

Overall sleep quality and sleep-related characteristics of the study participants by quartiles of Dietary Inflammatory Index (DII).

	DII Quartiles
	Q1	Q2	Q3	Q4	p-Value
Adequate sleep quality, n (%)	357 (72.6)	339 (66.5)	340 (68.4)	278 (63.6)	0.03
Sleep duration, n (%)					0.71
>7 h	296 (60.2)	316 (62.0)	292 (58.8)	260 (59.5)
6–7 h	121 (24.6)	108 (21.2)	106 (21.3)	100 (22.9)
5–6 h	49 (10.0)	58 (11.4)	71 (14.3)	52 (11.9)
<5 h	26 (5.3)	28 (5.5)	28 (5.6)	25 (5.7)
Sleep disturbance, n (%)					0.04
None	70 (14.2)	53 (10.4)	57 (11.5)	36 (8.2)
Low	366 (74.4)	373 (73.1)	368 (74.0)	330 (75.5)
Medium	56 (11.4)	84 (16.5)	72 (14.5)	71 (16.2)
High	0	0	0	0
Sleep latency, n (%)					0.17
Very short	227 (46.1)	240 (47.1)	221 (44.5)	170 (38.9)
Short	157 (31.9)	152 (29.8)	173 (34.8)	147 (33.6)
Medium	83 (16.9)	85 (16.7)	79 (15.9)	86 (19.7)
Long	25 (5.1)	33 (6.5)	24 (4.8)	34 (7.8)
Day dysfunction due to sleepiness, n (%)					0.30
None	300 (61.0)	273 (53.5)	273 (54.9)	234 (53.5)
Low	163 (33.1)	196 (38.4)	181 (36.4)	159 (36.4)
Medium	27 (5.5)	39 (7.6)	41 (8.2)	42 (9.6)
High	2 (0.4)	2 (0.4)	2 (0.4)	2 (0.5)
Sleep efficiency, n (%)					0.27
High	360 (73.2)	365 (71.6)	342 (68.8)	303 (69.3)
Medium	64 (13.0)	75 (14.7)	82 (16.5)	68 (15.6)
Low	27 (5.5)	32 (6.3)	21 (4.2)	33 (7.6)
Very low	41 (8.3)	38 (7.5)	52 (10.5)	33 (7.6)
Self-rated sleep quality, n (%)					<0.05
Very low	16 (3.3)	16 (3.1)	13 (2.6)	21 (4.8)
Low	57 (11.6)	91 (17.8)	70 (14.1)	61 (14.0)
Medium	301 (61.2)	286 (56.1)	307 (61.8)	276 (63.2)
High	118 (24.0)	117 (22.9)	107 (21.5)	79 (18.1)
Need of medication to sleep, n (%)					0.44
Not during the past month	453 (92.1)	453 (88.8)	447 (89.9)	391 (89.5)
Less than once a week	16 (3.3)	23 (4.5)	20 (4.0)	15 (3.4)
Once or twice a week	5 (1.0)	13 (2.5)	16 (3.2)	13 (3.0)
Three or more times a week	18 (3.7)	21 (4.1)	14 (2.8)	18 (4.1)